LO 3.38: The student is able to describe a model that expresses key elements to show how change in signal
transduction can alter cellular response.
SP 1.5: The student can reexpress key elements of natural phenomena across representations in the Domain
Explanation: A signal transduction pathway is where signal transduction occurs. Signal transduction occurs
when an extracellular signaling molecule activates a specific receptor located on the cell surface or inside the
cell. Receptor then causes a chain of event with in the cell, causing a cellular response. Signal transduction
pathways can be altered. Signal transduction pathways can be blocked by the use of drugs such as
antihistamines. Also signal transduction pathways being blocked can act as a preventative against diseases. A
more specific impact of drugs altering cellular response is antihistamines. This changing signal transduction
is how the antihistamines block transduction by blocking the histamine that is released by the cells immune
system. When a foreign antigen binds to the IgE on the mast cell there is a signal transduction that causes a
release of histamine. The antihistamines bind to the receptors in which histamines are trying to activate
which nullifies cellular response. Conditions where signal transduction is blocked or defective can be
deleterious, preventative or prophylactic (medication designed to prevent disease).
M.C. Question: Which of the following statements is true regarding a change in a signal transduction pathway
A) It can lead to the deactivation of a cellular response.
B) It can involve the disruption of a receptor in the cell.
C) A change in the signal transduction pathway can never be harmful in a cell
D) Both A and B are true
Learning Log/FRQ-style Question: Identify one way in
which a change in signal transduction can alter
cellular response. Give one specific example of how a
signal transduction pathway can be blocked.
ANSWER KEY– LO 3.38
M.C. Question: Which of the following statements is true regarding a change in a
signal transduction pathway
A) It can lead to the deactivation of a cellular response.
B) It can involve the disruption of a receptor in the cell.
C) A change in the signal transduction pathway can never be harmful in a cell
D) Both A and B are true
Learning Log/FRQ-style Question:
Identify one way in which a change in signal
transduction can alter cellular response. Give
one specific example of how a signal
transduction pathway can be blocked.
Cellular response can be altered by the signal
transduction pathway being blocked , which can
cause the cellular response to not occur. An example
of this is antihistamine binding to a receptor that
receives histamine. Which then causes no activation
because histamine cannot bind. Cellular response
can be altered by the signal transduction pathway.
LO 2.19: The student is able to make predictions about how positive feedback mechanisms amplify activities and processes in
organisms based on scientific theories and models.
SP 6.4: The student can make claims and predictions about natural phenomena based on scientific theories and models.
Explanation: A positive feedback loop works in the human body to enhance an already existing response. It allows for the
rapid amplification of a response such as the uterine contractions generated by oxytoxin, which is rapidly increased in
concentration through a positive feedback loop when a mother goes into labor. Another example is the enzyme pepsinogen,
usually secreted in small quantities by the stomach. Normally, the enzyme is inactive, but when pepsinogen is converted to
the active enzyme pepsin, the upregulation of pepsin signals increased conversion of pepsinogen to pepsin, until pepsin is in
a large enough concentration to digest protein from food. Without the positive feedback loop, if the stomach produced large
amounts of active pepsin continuously, it would digest its own cell lining.
M.C. Question: Which of the following is not a function of positive feedback loops?
A) Upregulating certain hormones
B) Maintaining homeostasis
C) Amplifying an existing response
D) Providing a larger and faster response than if the cellular response
did not involve a positive feedback loop
FRQ-Style Question: Student A observes several samples of mouse tissue
under a microscope and notes that when an incision is made in a blood vessel,
a few platelets are initially released to the wound site. After an hour, she
returns and is astonished to note a huge increase in platelet concentration.
She continues to check up on the tissue samples each hour for 5 hours and records
exponential increases in platelet concentration. Propose a reasonable biological
explanation for her findings and explain your reasoning. What are the processes
behind the exponentially increased platelet concentration, and why is it not always
beneficial to have high concentrations of platelets in the blood?
http://slideplayer.com/slide/1498558/
ANSWER KEY: LO 2.19
M.C. Question: Which of the following is not a function of positive feedback loops?
A) Upregulating certain hormones
B) Maintaining homeostasis
C) Amplifying an existing response
D) Providing a larger and faster response than if the cellular response
did not involve a positive feedback loop
FRQ-Style Question: Student A observes several samples of mouse tissue
under a microscope and notes that when an incision is made in a blood vessel,
a few platelets are initially released to the wound site. After an hour, she
returns and is astonished to note a huge increase in platelet concentration.
She continues to check up on the tissue samples each hour for 5 hours and records
exponential increases in platelet concentration. Propose a reasonable biological
explanation for her findings and explain your reasoning. What are the processes
behind the exponentially increased platelet concentration, and why is it not always
beneficial to have high concentrations of platelets in the blood?
Platelets are produced in the bone marrow and released to circulate in the blood, where they
attach to and repair incisions in blood vessels. Platelet concentration at a wound site is controlled
by a positive feedback loop. Platelets circulating through nearby blood vessels will initially
attach to the wound site and release PAF (platelet-activating factor), which will signal
more platelets to be released into the blood from the bone marrow and attach to the
wound site. This positive feedback loop continues until the platelets are in a high enough
localized concentration to plug the incision by forming a clot. After the clot is formed,
platelet concentration returns to normal levels. The positive feedback loop is necessary
to quickly amplify platelet concentration so that a clot may stop blood leaking from the
incision. Having a constant high concentration of platelets, a condition known as
thrombocytosis, can lead to unnecessary clotting of blood vessels which in turn can cause
heart attacks or strokes.
http://images.frompo.com/bd7393b5d0f4e001ce0d563a7ba56e24
LO 3.44
•
LO 3.44 – The student is able to describe how nervous systems detect external and internal signals
•
SP 1.2 - The student can describe representations and models of natural or manmade phenomena and systems in the
domain.
•
•
•
Explanation – The ability for an organism to respond to external stimuli is called sensitivity. A stimulus is exposed to a
sensory receptor, which elicits a reflex via stimulus transduction. These sensory receptors will receive info from outside the
body of the organism, as in touch receptors found in the skin or light receptors in the eye, as well as internal detectors, such
as chemoreceptors, which are sensory receptors that traduces a chemical signal into an action potential, and
mechanoreceptors, which are excited by mechanical pressures or distortions, as those responding to touch and muscular
contractions. Once stimulus reaches threshold, the neuron is fired and info is sent across synapses to the Central Nervous
System (CNS), where it is integrated into a decision making process, which determines whether or not you have a reaction.
M.C. Question: Which of the following is true about stimuli detection?
A) Only mammals can detect different stimuli
B) The Sympathetic Nervous system determines stimulus response
C) Stimulus must reach a threshold during action potential to send info
D) Hair receptors which make up toenails assist in lower body detection
Learning Log/ FRQ-style Question:
Suppose you are outside on a nature trip and a bird flies over you and
poops on your hand. Explain the processes involved in detecting and
processing the stimulus. Then, describe one internal and external receptor
used in the human body.
Answer Key
Which of the following is true about stimuli detection?
A) Only mammals can detect different stimuli
B) The Sympathetic Nervous system determines stimulus response
C) Stimulus must reach a threshold during action potential to send info
D) Hair receptors which make up toenails assist in lower body detection
Suppose you are outside on a nature trip and a bird flies over you and
poops on your hand. Explain the processes involved in detecting and
processing the stimulus. Then, describe one internal and external receptor
used in the human body.
Once the external stimulus of bird fecal matter is detected by sensory
receptors in the eye and on the affected area of skin, the sensory input
travels to different cells via the signal transduction pathway, where the
stimuli signal info is received by dendrites in the neuron, and once action
potential is reached due to depolarization, info is sent to the brain for
interpretation which is translated into a motor output, or your reaction. An
external receptor include Exteroceptors report the senses of sight, hearing,
smell, taste, and touch. Internal receptors include chemoreceptors, which
tranduces a chemical signal into an action potential.
LO 4.3: The student is able to use models to predict and justify that changes in the subcomponents of a biological
polymer affect the functionality of the molecule.
SP 6.1: The student can justify claims with evidence
SP 6.4: The student can make claims and predictions about natural phenomena based on scientific theories and models.
Explanation: The central dogma of biology is the arise of proteins by transcription of a DNA strand into an RNA strand and
the translation of that molecule into a protein. The subcomponents of proteins are amino acids. One mutation in the template
strand or the transcribed RNA strand may result in a change in the structure and function of the resulting protein/amino acid
sequence. DNA is read from the 3’ to 5’ ends in transcription and the resulting RNA strand in translated from 5’ to 3’. One
mutation can result in an amino acid chain with an entirely different structure and function or the same structure and function
due to the redundancy of the codons that code for similar amino acids. Lipids, carbohydrates and nucleic acids exhibit the
same relationship between its subcomponents and its structure and function. Identifying the change and how it relates to the
resulting polymer’s structure is necessary.
M.C. Question:A template strand of DNA is given below.
5’- AGT-GCA-GTC-AAC-3’
Using the codon chart provided, if the cytosine (C)
nearest the 3’ end was changed to thymine (T),
what would the result be?
A) Val is replaced by Ile
B) A stop codon is produced
C) No change occurs due to a silent mutation
D) Thr is replaced by Asp
E) Both A and D
FRQ-Style Question: A template strand of DNA is
given below:
5’ A G C T A A G T T C G A A T A C A G G A T C C A G C G 3’
Explain why a mutation of the bolded guanine near the
3’ end will not have an affect on the resulting protein
produced.
Explain why a mutation of the bolded adenine to
thymine would result in a drastic change for the resulting
protein.
Answer Key – LO 4.3
M.C. Question:A template strand of DNA is given below.
5’- AGT-GCA-GTC-AAC-3’
Using the codon chart provided, if the cytosine (C)
nearest the 3’ end was changed to thymine (T),
what would the result be?
A) Val is replaced by Ile
B) A stop codon is produced
C) No change occurs due to a silent mutation
D) Thr is replaced by Asp
E) Both A and D
FRQ-Style Question: A template strand of DNA is
given below:
5’ A G C T A A G T T C G A A T A C A G G A T C C A G C G 3’
Explain why a mutation of the bolded guanine near the 3’
end will not have an affect on the resulting protein produced.
Explain why a mutation of the bolded adenine to thymine would result
in a drastic change for the resulting protein.
Regardless of the third base pair in the codon translated, the amino acid arginine will be produced. This
type of mutation is known as a silent mutation since there is no difference between the pre and postmutated gene encoding for the protein. A mutation of the third base pair in the codon involving the bolded
adenine to thymine would result in the production of a stop codon. This will drastically change the
resulting protein’s structure and function.
LO 4.8: The student is able to evaluate scientific questions concerning organisms that exhibit complex properties due to the
interaction of their constituent parts.
SP 3.3: The student can evaluate scientific questions
Explanation: For example, in order for animals to obtain nutrients from their food, the food must first go
through the digestive system and be processed through organs such as the stomach, which breaks down
the food with enzymes, and the small intestines, which further breaks the food down into nutrients that
can be absorbed through it’s lining. However, the process of moving food through the digestive system
requires the use of energy, or ATP. In the processing of making ATP, oxygen is used in the ETC as a final
electron acceptor. This oxygen is obtained through the respiratory system in the lungs and absorbed and
transported through circulatory system.
M.C. Question: Which of the following statements about system/organ
interactions is true?
A) The kidneys return unused nutrients into the digestive system
B) The lymphatic system eliminates antigens that are found in the blood.
C) When the neurons are aroused, thyroxin is released from the thymus
D) The integumentary system and the muscular system work together to make
and utilize vitamin D
Learning Log/FRQ-style Question: The endocrine system is one of the more
important bodily systems, affecting almost every other system through the use of
hormones. Describe three hormones released by the endocrine system and how
they affect other systems in the body.
Answer Key- LO 4.8
Which of the following statements about system/organ interactions is true?
A) The kidneys return unused nutrients into the digestive system
B) The lymphatic system eliminates antigens that are found in the blood.
C) When the neurons are aroused, thyroxin is released from the thymus
D) The integumentary system and the muscular system work together to make and utilize vitamin D
The endocrine system is one of the more important bodily systems, affecting almost every other system through the use of hormones.
Describe three hormones released by the endocrine system and how they affect other systems in the body.
When epinephrine, aka adrenaline, is released into the bloodstream by the adrenal glands, our flight or fight response is triggered. This
hormone diverts blood flow by restricting blood vessels in the digestive system, thus slowing it down, and dilating blood vessels in the
muscular system, giving the muscles more oxygen and thus the energy needed to flee in a stressful situation. Antidiuretic hormone, or
ADH, is released by the pituitary gland to regulate water in the body. When water levels are low in the blood, the hypothalamus signals
to the pituitary gland to release ADH which then travels to the kidneys in the urinary system, causing a higher uptake of water and more
concentrated urine. When water levels are high, ADH production is stopped and less water is taken up. Parathyroid hormone is a
hormone released by the parathyroid used to control calcium levels in the blood. As calcium levels become low, PTH stimulates the
release of calcium, slowing down the formation of new bones in the skeletal system. High levels of PTH can cause kidney disease and
weak bone structure.
LO 2.3: The student is able to predict how changes in free energy availability affect organisms,
populations,
and ecosystems.
SP 6.4: The student can make claims
and predictions
about natural phenomena based on
scientific
theories
andexperience
models. a logical pathways of energy synthesis.
Explanation: All organisms that consume
or make
energy
As in the ten step anaerobic process of glycolysis, a six-carbon molecule is broken down into 3-carbon
molecules of G3P that will be turned into pyruvate. The pyruvate can later be used to produce more ATP.
Two ATP are consumed in the production of the two pyruvates, steps one and three being catalyzed by
kinases. Whereas energy is consumed in the first five steps of glycolysis, the next five steps produce energy.
Four ADPs are phosphorylated and turned into ATPs in steps seven and ten, also carried out by kinases. All
the ATP produced is a result of all G3P molecules made in steps four and five. Two NADH and four ATPs
are made, though there is only a net of two ATP, the other two being spent to create the two pyruvate of the
first and third steps. The electron carrier NADH is formed in the sixth reaction by an enzyme. NADH will
eventually helps to carry electrons down the electron transport chain that will create even more ATP by
spinning the ATP synthase during oxidative phosphorylation. ATP drives many other biochemical pathways
such as anaerobic fermentation or the aerobic Krebs cycle.
MC Question: When plants are overwatered and consequently experience oxygen deprivation during their period of dark
respiration (taking in oxygen and releasing carbon dioxide at night), they begin anaerobic respiration. Which of these steps
will the plant NOT undergo?
a) the plant will die in a few days due to lack of oxygen and its inability to produce enough ATP to sustain itself
b) a decrease in the amount of ATP produced
c) a lengthening of the roots to reach drier soil
d) self-fermentation of the plant via the creation of ethanol
FRQ Question: Polar pyruvate must experience active
transport across the mitochondrial membrane in order to
facilitate the Krebs cycle in the form of Acetyl CoA.
Describe how Acetyl CoA is produced and the process
carried out by this molecule. Diagrams may be
incorporated into your answer.
•
MC Question: When plants are overwatered and consequently experience
oxygen deprivation during their period of dark respiration (taking in oxygen and
releasing carbon dioxide at night), they begin anaerobic respiration. Which of
these steps will the plant NOT undergo?
• a) the plant will die in a few days due to lack of oxygen and its inability to
produce enough ATP to sustain itself
example diagram
• b) a decrease in the amount of ATP produced
• c) a lengthening of the roots to reach drier soil
• d) self-fermentation of the plant via the creation of ethanol
FRQ Question: Polar pyruvate must experience
active transport across the mitochondrial membrane
in order to facilitate the Krebs cycle where it is
converted to Acetyl CoA. Describe how Acetyl
CoA is produced and the process it aids. Diagrams
may be incorporated into your answer.
Acetyl CoA is a product of broken down carbohydrates from glycolysis
and fatty acid oxidation which contributes the coenzyme A. In the
membrane, carbon dioxide is broken off from pyruvate, which is then
oxidized by NAD+, creating Acetyl CoA by adding the coenzyme A.
Two carbon dioxide molecules are lost and two NADH, eventual
electron carriers, are made from the oxidization of citric acid. Carbon
joins the Acetyl CoA but is replaced by a phosphate group, creating an
ATP molecule. Two hydrogens are then lost, and FAD is turned into
FADH2, which will be oxidized to produce ATP. Since the Krebs cycle
LO 1.12: The student is able to connect scientific evidence from many scientific disciplines to support the modern concept of evolution
SP 7.1: The student can connect phenomena and models across spatial and temporal scales
Explanation: The concept of evolution is supported by many different scientific disciplines. Paleontologists have studied fossils, finding homologous structures bones of the same shape and/or function found across many different species - which indicate a common ancestor. Additionally, the study of genetics has
supported evolution. Scientists have been able to examine DNA sequences of many different species. In doing so, they have found that segments of
identical DNA sequences can be found in different species. Because of biostatistics, and specifically the BLAST database, scientists are able to compare the
DNA of many different species whose DNA has been sequenced and added to the database. More similarities in the DNA indicate evolution from a more
recent ancestor. Even research at the cellular level is supportive of evolution. The endosymbiotic theory states that a bacteria engulfed another
prokaryotic cell - creating a symbiotic relationship and giving rise to eukaryotes as we know them today. Evolutionary biology, such as the studies done on
the Galapagos islands by Charles Darwin, have shown how environmental stress can change the allelic frequency in a gene pool.
M.C. Question: Student A is examining diagrams that show the shape of a human skull and that of a gorilla and suggests that their similar structure and function
strongly suggest a common ancestor for the two species. Student B states that only examination of the DNA of the two species could possibly indicate a
common ancestor for the two species. Which student is correct and why?
A. Student B - genetic testing is a far more advanced method of determining the possibility of a common ancestor.
B. Student B - student A has pointed out an analogous structure, developed over time from exposure to a similar environment.
C. Student A - this examination of fossils has lead him to the correct conclusion that the gorilla and human skulls are homologous structures, providing evidence
that the two descended from a common ancestor.
D. Neither student is correct - neither genetic biology or paleontology can be used to suggest evolution. Only long evolutionary studies like that of Charles
Darwin can do that.
Learning Log/FRQ style Question: The concept of evolution has been supported throughout many scientific disciplines. Choose three pieces of evidence
supporting evolution and explain how they do.
Student A is examining diagrams that show the shape of a human skull and that of a gorilla and suggests that their similar structure and
function strongly suggest a common ancestor for the two species. Student B states that only examination of the DNA of the two species
could possibly indicate a common ancestor for the two species. Which student is correct and why?
A. Student B - genetic testing is a far more advanced method of determining the possibility of a common ancestor.
B. Student B - student A has pointed out an analogous structure, developed over time from exposure to a similar environment.
C. Student A - this examination of fossils has lead him to the correct conclusion that the gorilla and human skulls are homologous
structures, providing evidence that the two descended from a common ancestor.
D. Neither student is correct - neither genetic biology or paleontology can be used to suggest evolution. Only long evolutionary studies like
that of Charles Darwin can do that.
The concept of evolution has been supported throughout many scientific disciplines. Choose three pieces of evidence supporting evolution
and explain how they contribute to the concept of evolution.
Charles Darwin’s study of the Galapagos Islands found the sizes of finch beaks varied amoung the islands proportionally to the types and
sizes of nuts and berries available. This showed how natural selection selects for traits beneficial to the species as their environmental
stress shifts, changing the allelic frequency of the gene pool and showing evolution. Paleontologists have studied fossils, like those of
homo-erectus, homo-habillus, and homo-sapien sapien. The structures of their bones show slow evolutionary changes to better suit our
species to our environment. Also, use of biostatistics like the BLAST database can be examined. A quick BLAST may find that the DNA of
two distinct species may be as similar as 90%, clearly indicating evolution from a fairly recent ancestor.
LO 2.4: The student is able to use representations to pose scientific questions
about what mechanisms and structural features allow organisms to capture,
store and use free energy.
SP 1.4 The student can use representations and
models to analyze situations or solve
problems qualitatively and quantitatively.
SP 3.1 The student can pose scientific questions.
Explanation: Plants capture and store free energy
through photosynthesis. In this, chlorophyll in
chloroplasts absorb light energy, which
excites electrons in Photosystem II and I,
which are embedded in the membrane.
When the excited electrons are transferred
along an electron transport chain, a proton
gradient is formed across the thylakoid
membrane. These protons then undergo
facilitated diffusion through ATP synthase to
be sent to the Calvin Cycle, along with the
NADPH created when the electrons reach the
end of the chain. In the Calvin Cycle, these
are used along with CO2 to make a simple
sugar, CH2O. This sugar molecule is how the
free energy is stored after being captured in
the light reactions. This can then be used in
cellular respiration, which makes ATP for the
cell to be able to do work.
M.C. Question: When glucose is split into pyruvate during glycolysis what kind of
reaction is this?
A)
Endergonic because it releases energy
B)
Exergonic because it requires energy
C)
Exergonic because it releases energy
D)
Endergonic because it requires energy
FRQ-style Question: Aerobic respiration produces 19 times as much ATP as
anaerobic respiration. Describe why this is and include a description of
both mechanisms.
ANSWER KEY – LO 2.4
When glucose is split into pyruvate during glycolysis what kind of reaction is this?
A)
Endergonic because it releases energy
B)
Exergonic because it requires energy
C)
Exergonic because it releases energy
D)
Endergonic because it requires energy
Aerobic respiration produces 19 times as much ATP as anaerobic respiration. Describe why this is. Include a
description of both mechanisms.
In aerobic respiration, glucose enters the cell and is split into 2 pyruvate molecules and produces a net of 2
ATP. The pyruvate enters the mitochondria and is converted into acetyl CoA, which can be used in
the Citric acid (Krebs) cycle, which produces 2 ATP since there are two pyruvate. This cycle also
makes NADH and FADH2 that will be used in oxidative phosphorylation. This includes the electron
transport chain and chemiosmosis. The NADH and FADH2 release the electrons they were carrying
onto the chain, which creates a high proton concentration in the intermembrane space. These
electrons are pulled along the chain by the Oxygen at the end, and make water when they get there.
When the protons undergo facilitated diffusion to achieve equilibrium, they pass through ATP
synthase, which creates between 32 and 34 ATP. This comes to around 38 ATP total from one glucose
molecule.
In anaerobic respiration, the oxygen is not present, so the electron transport chain cannot function. Instead,
the glucose is split into the two pyruvate and 2 ATP is made. But then the pyruvate is fermented in
the cytosol into lactate or ethanol. This makes a total of only 2 ATP, as compared to 38 from aerobic
respiration.
LO 1.28: The student is able to evaluate scientific questions based on hypotheses about the origin of life on Earth
SP 3.3: The student can evaluate scientific questions
Explanation: There are several theories as to how life became on Earth. One theory hypothesizes that the primitive
atmosphere contained inorganic precursors from which organic molecules could have been synthesized through natural
chemical reactions catalyzed by the input of energy. These molecules then served as monomers for the formation of more
complex molecules like amino acids and nucleotides. Other theories and models suggest that primitive life developed on
biogenic surfaces such as clay, that served as templates and catalysts for the assembly of macromolecules. The question is
still unanswered as to whether the first genetic and self-replicating material was DNA or RNA. Stanley Miller and Harold
Urey conducted an experiment that involved running an electric current through an apparatus containing molecules
believed to represent the atmospheric conditions of early Earth. Through this experiment, they observed the formation of
some organic compounds as well as amino acids. The theory of Endosymbiosis explains the origin of chloroplasts and
mitochondria and their double membranes. This concept postulates that chloroplasts and mitochondria are the result of
years of evolution initiated by the endocytosis of bacteria and blue-green algae. According to this theory, blue green algae
and bacteria were not digested; they became symbiotic instead.
M.C. Question: The Endosymbiotic theory
gives the reason for the origin of the
mitochondria and what other organelle?
A) Ribosomes
B) Golgi apparatus
C) Cilia
D) Chloroplast
FRQ: What was the Miller-Urey experiment
and how was it performed? What were the
results of the experiment?
Answer Key- LO 1.28
The Endosymbiotic theory gives the reason for the origin of the mitochondria and what other organelle?
A) Ribosomes
B) Golgi apparatus
C) Cilia
D) Chloroplast
What was the Miller-Urey experiment and how was it performed? What were the results of the experiment?
The Miller-Urey experiment was an experiment that simulated they conditions similar to primitive Earth
using an apparatus. This apparatus contained methane, ammonia, hydrogen, and water, along with a
continuous electric current to simulate lightning. Analysis of the experiment was done by chromatography.
At the end of one week, Miller observed that as much as 10-15% of the carbon was now in the form of
organic compounds. Two percent of the carbon had formed some of the amino acids which are used to
make proteins. And in conclusion, Miller's experiment showed that organic compounds such as amino acids,
which are essential to cellular life, could be made easily under the conditions that scientists believed to be
present on the early earth.
LO 3.17 The student is able to describe representations of an appropriate example of inheritance
patterns that cannot be explained by Mendel’s model of the inheritance of traits.
SP 2.1: The student can describe representations and models of natural or man-made phenomena and
systems in the domain.
FRQ Question:
Gray and Kate are having an argument. Gray
argues that it is possible to determine blood
types using the basic Mendelian model. Kate
argues that Gray is wrong, and that blood
groups in humans are determined by multiple
alleles of a single gene. Who is right and why?
Explain why the concept of the Mendelian
model and the concept of multiple alleles
contrast each other. Name an additional
example of a discovery in science that
contradicts the original Mendelian model.
Explain.
Explanation:
Mendel’s model only provides two alleles, and a way to
determine genotypes and phenotypes through one gene.
However, other later discoveries in science have proved more
complex than this basic genetic model, such as phenomena like
pleiotropy and multiple alleles. The main example in science is
blood types, and the student should be able to recognize this as
a major example of an exception, along with being able to
recognize that some diseases and traits are a result of a more
complex inheritance pattern. The student is able to describe
representations in the body of ways in which certain
phenotypes cannot be explained by the Mendel model, and
could be a result of multiple genes, alleles, mutations, etc. ,
with thorough explanations of alternative inheritance patterns.
Multiple Choice Question:
Which of the following is an example of an inheritance pattern that cannot be explained
by Mendel’s model of inheritance of traits?
A. Achondroplasia
B. Sickle Cell Disease
C. Cystic Fibrosis
By Laura Nicklas, 4th period
D. Tay Sachs Disease
LO 3.17 Answer Key
Multiple Choice Question:
Which of the following is an example of an inheritance
pattern that cannot be explained by Mendel’s model of
inheritance of traits?
A. Achondroplasia
B. Sickle Cell Disease
C. Cystic Fibrosis
D. Tay Sachs Disease
FRQ Response
Gray and Kate are having an argument. Gray argues that it is possible to
determine blood types using the basic Mendelian model. Kate argues that
Gray is wrong, and that blood groups in humans are determined by multiple
alleles of a single gene. Who is right and why? Explain why the concept of the
Mendelian model and the concept of multiple alleles contrast each other.
Name an additional example of a discovery in science that contradicts the
original Mendelian model. Explain.
Kate is right. In Mendel’s model, only two alleles exist. However, in real life,
most genes in populations have more than two allelic forms. Blood groups in
humans, ABO, come from multiple alleles of a single gene, resulting in four
possible phenotypes, and arise from three different alleles in red blood cells.
For example, an enzyme encoded by the i allele adds neither A or B. The
concept of multiple alleles contradicts the Mendelian model because the
model only has two alleles. Another example is epistasis. This is when a gene
at one locus alters the phenotypic expression of a gene at a second locus.
The original Mendelian model only addresses one gene, while epistasis
involves the interaction between two genes and their effect on phenotypes.
LO 2.32: The student is able to use a graph or diagram to analyze situations or solve problems (quantitatively
or qualitatively) that involve timing and coordination of events necessary for normal development in an
organism.
SP 1.4: The student can use representations and models to analyze situations or solve problems qualitatively
and quantitatively.
Explanation: For a developing organism timing and coordination of events play an important role in the
normal development of an organism. For many plants seeds will only germinate when the conditions are
right for that species. During embryonic development cell undergo differentiation to determine cell fate.
Transcription factors will activate the appropriate homeotic genes to determine the key to cell, tissue,
organ, and organism identity. This will result in sequential gene expression and through the use of
extracellular signals we see coordination between the adjacent cells that leads to sequential gene expression
and differentiation. Apoptosis also plays an important role in embryonic development by contributing to the
appropriate formation of various organs and structure. This whole process of embryonic induction in
development results in the correct timing of events so that organisms can develop normally.
•M.C. Question: Which of the four graphs
would you expect to represent the cell
count over time for a region that is
undergoing apoptosis?
A) A
B) B
C) C
D) D
•Free Response: Based on the above diagram why would it be
beneficial for a seed to germinate very quickly in the optimal
temperature while taking long periods of time to germinate
when it is higher or lower than the optimal temperature.
What other conditions could effect germination.
Answer Key-LO 2.32
•M.C. Question: Which of the four graphs would
you expect to represent the cell count over time
for a region that is undergoing apoptosis?
•A)A
B)B
C)C
D)D
•Free Response: Based on the above
diagram why would it be beneficial for a
seed to germinate very quickly in the
optimal temperature while taking long
periods of time to germinate when it is
higher or lower than the optimal
temperature. What other conditions could
effect germination.
It would be beneficial for the seed to germinate quickly when the optimum temperatures are
available because it would be during those times that conditions would be best suited for that
organism to survive in. It is beneficial to wait longer periods of time when conditions are not
optimal because if it were to germinate then its chances of survival would be diminished. Other
conditions that could effect germination could be availability of water, availability of oxygen in
the soil, and availability of sunlight.
LO3.49:The Student is able to create a visual representation to describe how nervous system transmit
information.
SP 1.1:The student can create representations and models of natural or man-made phenomena and
systems in the domain.
Signals are sent down dendrite to the neuron from the axon hillock down the axon down the cell
body by jumping node to node thanks to the node of Ranvier by 120 m/sec. It has two channels
Na+ or K+; K+ channels open letting K+ in this becomes more negative (hyperpolarization) or
positive by Na+ channels (depolarization). When axon charge hits its threshold of -55mv by Na+
going in, it’s a action potential. To reset it self it opens K+ channels & opposite attract allowing
Na+ out the neuron till it’s back to -70mv. The end of axon chemical synapse is used to change
electric signal to chemical back to electric to travel down the neuron. Because of the action
potential getting to terminus of the pre-synaptic cell; this cause volted gated Ca+2 channels to
open allowing it to diffuse in the concentration gradient. Allowing vesical holding the
neurotransmitter to fuse with membrane; letting neurotransmitter to bind on the cell; which is used
to open the ligand gated channels to let in K+ or Na+ in the cell till it’s remove
M.C.? Which of the statements is false of a signal going down the axon?
A.When reaching a threshold of -55mv Na+ channels open and K+ close to reset the
neuron back to its original point of -70mv
B.Chemical synapse is used to be able to “jump” the signal down to the
next neuron
C. Action potential signal goes further away because it’s positive and is
attracted to the negative charge further down.
D. Dendrite receives the signal which is sent down to the axon
hillock which is sent down to the axon.
Learning Log/FRQ-Style
Suppose you were asked what are the many different ways for a signal to be
stopped and describe how and why does it stop it.
Answer Key
M.C.? Which of the statements is false of a signal going down the axon?
A.When reaching a threshold of -55mv Na+ channels open and K+ close to reset the
neuron back to its original point of -70mv
B.Chemical synapse is used to be able to “jump” the signal down to the
next neuron
C. Action potential signal goes further away because it’s positive and is
attracted to the negative charge further down.
D. Dendrite receives the signal which is sent down to the axon
hillock which is sent down to the axon.
Suppose you were asked what are the many different ways for a signal to be
stopped and describe how and why does it stop it.
The signal can be stop neuron dendrites is not able to receive the signal to pass down the
cell body to the axon hillock to lead it to the axon so it can be sent down the cell. And
down the axon there could Na+ channels not opening to cause an action potential to be
release and stay at -70mv this stops the signal from being able to happen at all. Last is it
goes down the neuron but is not passed down chemical synapse to be passed to other
neruons this could be by the action potential being pass down or the neurotransmitter is
not being able to reach the ligand because of no diffusion thru the concentrated gradient
or the receptor is deformed to not fit the shape. With out the neuron being able to send
down a signal then there is no possible way for it to respond to pain which can cause long
LO 1.15: The student is able to describe specific examples of conserved core biological processes and features shared by
all domains or within one domain of life, and how these shared, conserved core processes and features support the
concept of common ancestry for all organisms
SP 7.2: The student can connect concepts in and across domain(s) to generalize or extrapolate in and/or across enduring
understandings and/or big ideas.
Explanation: Amongst all forms of life (Archaea, Bacteria, and Eukarya, both extant and extinct), there exists 3 main things
that we all share: DNA and RNA as carriers of genetic information, a universal genetic code, and many metabolic
pathways. On top of that, Eukaryotes also share the presence of a cytoskeleton (a network of structural proteins that
facilitate cell movement, morphological integrity and organelle transport), a nucleus, membrane-bound organelles
(mitochondria and/or chloroplasts) , linear chromosomes and endomembrane systems. These lead to the fact that all
organisms both living and dead are descendants of a single common and universal ancestor, and that we all evolved
from it initially,
M.C. Question: Of the following core biological processes, which are shared by all domains of life?
I: Membrane Bound Organelles in all cells
II: DNA or RNA as genetic code
III: A nucleus in all cells
IV: Metabolic pathways
A) I only
B) II only
C) I and III
D) II and IV
Free Response Question : Explain 2 core biological
processes or features that all living things both share
and have shared since a single common ancestor.
Justify your answers with descriptions of each
process.
M.C. Question: Of the folowing core biological processes, which are shared by all domains of life?
I: Membrane Bound Organelles in all cells
II: DNA or RNA as genetic code
III: A nucleus in all cells
IV: Metabolic pathways
A)
B)
C)
D)
I only
II only
I and III
II and IV
Free Response Question : Explain 2 core biological
processes or features that all living things both share and
have shared since a single common ancestor.
Justify your answers with descriptions of each process.
All forms of life have some sort of genetic material, specifically DNA or RNA, which doesn't have to be inside
a nucleus (bacteria). This genetic material must be transcribed, translated and replicated in some way.
Additionally, major features of this genetic code must be somewhat similar to all other living things
(DNA is made up of A, T, C, and G). The second thing shared by all organisms is that metabolic signaling
transduction pathways are present, whether it be a response to external signals by bacteria that
influences cell movement or epinephrine stimulation of glycogen breakdown in mammals.
L.O. 2.21 – The student is able to justify the selection of the kind of data needed to answer the scientific questions about
the relevant mechanism that organisms use to respond to changes in their environment.
S.P. 4.1 - The student can justify the selection of the kind of data needed to answer a particular scientific question.
Explanation – One of an organisms primary goals is to maintain homeostasis, meaning it wants to maintain a constant
balance inside the body of necessary life functions. This, however, is not always possible. When an organism encounters
an outside stress, they will use an adaptation that allows them to maintain energy. For example: in very hot or cold
temperatures, when resources might be scarce, some animals go into what is called torpor, a physiological state in which
activity is low and metabolism decreases. In a long term scenario torpor is called hibernation. Other organisms have
similar mechanisms such as sweating and shivering in humans, circadian rhythm in animals, or chemotaxis in bacteria.
Thus, this objective means one must be able to select the kind of data (quantitative vs. qualitative) necessary to explain
what type of mechanism you’re talking about. For example, the chart below is an example of quantitative data, giving a
numerical summary of metabolism use during hibernation. (Figure: Metabolism during hibernation chart).
MC – If a Belding’s Ground Squirrel population is hibernating during the winter, and you wanted to see how much
energy stored as body fat was being used as a percentage, what data would you be looking at, and would it be qualitative
or quantitative.
(a) Glucose use, quantitative
(b) Glucose use, qualitative
(c) Lipid use, quantitative
(d) Lipid use, qualitative
(e) Steroid use, quantitative
Free Response – You are studying hibernation in grizzly bears
and you want to see how antibody production was affected
during hibernation
(a) Design an experiment to test the amount of antibodies present
in a grizzly bear’s system before and after hibernation.
(b) Justify what type of data you would use in this experiment, and
why you would be using it in this context.
MC – If a Belding’s Ground Squirrel population is hibernating during the winter, and you wanted to see how much
energy stored as body fat was being used as a percentage, what data would you be looking at, and would it be qualitative
or quantitative.
(a) Glucose use, quantitative
(b) Glucose use, qualitative
(c) Lipid use, quantitative
(d) Lipid use, qualitative
(e) Steroid use, quantitative
FRQ – You are studying hibernation in grizzly bears and you want to see how antibody production was affected during hibernation
(a) Design an experiment to test the amount of antibodies present in a grizzly bear’s system before and after hibernation.
(b) Justify what type of data you would use in this experiment, and why you would be using it in this context.
(a) – I would take a sample of the population of grizzly bears and randomly select them for either the control or the experimental
unit. First we would test each bear for the presence of antibodies in their systems at that moment. The bears would be separated
into a group that would be allowed to hibernate normally and a group that would be kept awake during the winter using
artificial conditions. At the end of the hibernation period both groups of bears would have an antibody count done to see if
while in hibernation, there was an immune system build up.
(b) - The primary measurements would be quantitative data, based on the fact that we are measuring the number of
antibodies/immunoglobulin's in the bears system. This numerical count will give us a much better picture of the immune
system affects of hibernation than an observational data summation. There is, however, an opportunity to collect qualitative
data as well. You ought make observational notes on the frequency and type of diseases a bear could catch, or on the physical
appearance of the two sets of bears. These would also be valid qualitative observations to make.
signaling pathway.
SP 1.4: The student can use representations and models to analyze situations or solve problems qualitatively and
quantitatively.
Explanation: Paracrine signaling involves local signaling, while endocrine signaling refers to long distance signaling involving hormones.
The first stage of a general cell signaling pathway is reception, where the ligand (a signal molecule) binds to a receptor. Then, the
received signal is converted to a specific cellular response via relay proteins in the process of transduction. Lastly, the cell responds to
the signal. There are four different kinds of receptors: intracellular (completely inside cell), g-protein linked (integral protein), receptor
tyrosine kinases (phosphorylates other molecules), and ion channel receptors ligand binding (makes receptor form a dimer). For
example, a pathway between a steroid hormone and intracellular receptor begins with the hormone passing through the plasma
membrane. Then, testosterone binds to a receptor protein to activate it the cytoplasm. Next, the hormone receptor complex enters the
nucleus to bind to particular genes. This bound protein promotes the transcription of the gene into mRNA, which is finally translated
into a specific protein. Transduction is the conversion of a received signal to a specific cellular response by the phosphorylation of
protein. The signal transduction pathway is the first step in a chain of molecular interactions that activates another protein that
activates another molecule, and so on. Relay proteins bring a signal from the receptor to a response. Also, a single ligand can activate
millions of molecules during a cell’s response to create signal amplification. The same signal can also create different responses because
of different receptor types, different relay proteins, and cross talking with different signals. Scaffolding proteins bind several different
molecules together for quicker communication. Signaling molecules that interact with a target cell activate second messengers, like
cAMP and calcium ions.
M.C. Question: Many signal molecules in animals produce response in target cells with signal
transduction pathways that increase the concentration of cytosolic calcium ions. Why does a small
change in the amount of ions represent a relatively large change in percentage of calcium
concentration?
A) Calcium ions are actively transported out of the cytosol from the ER and are actively transported
into the cell, so the calcium concentration in the ER is lower than that of the cytosol.
B) Calcium ions are actively imported from the cytosol into the ER and are actively transported out of
the cell, so the calcium concentration in the ER is higher than that of the cytosol.
C) Calcium ions are actively imported from the cytosol into the ER and are actively transported out of
the cell, so the calcium concentration in the ER is lower than that of the cytosol.
D) Calcium ions are actively transported out of the cytosol from the ER and are actively transported
into the cell, so the calcium concentration in the ER is higher than that of the cytosol.
Learning-Log/FRQ Style question:
Part a: Explain why liver cells and heart cells respond to some signals but ignore others, and why
some signals trigger different responses in both, despite the fact both are exposed to local regulators
and hormone molecules via the blood stream. (ex: epinephrine stimulates liver to break down
glycogen, but causes heart to contract)
Part b: Explain why a small number of epinephrine molecules binding to the receptors on the surface
of a liver cell leads to the release of hundreds of millions of glucose molecules from glycogen.
ANSWER KEY- LO 3.33
Many signal molecules in animals produce response in target cells with signal transduction pathways that increase the
concentration of cytosolic calcium ions. Why does a small change in the amount of ions represent a relatively large
change in percentage of calcium concentration?
A) Calcium ions are actively transported out of the cytosol from the ER and are actively transported into the cell, so the
calcium concentration in the ER is lower than that of the cytosol.
B) Calcium ions are actively imported from the cytosol into the ER and are actively transported out of the cell, so the
calcium concentration in the ER is higher than that of the cytosol.
C) Calcium ions are actively imported from the cytosol into the ER and are actively transported out of the cell, so the
calcium concentration in the ER is lower than that of the cytosol.
D) Calcium ions are actively transported out of the cytosol from the ER and are actively transported into the cell, so the
calcium concentration in the ER is higher than that of the cytosol.
Describe the following effects of the properties of transduction pathways on cells.
Part a: Explain why liver cells and heart cells respond to some signals but ignore others, and why some signals trigger
different responses in both, despite the fact both are exposed to local regulators and hormone molecules via the blood
stream. (ex: epinephrine stimulates liver to break down glycogen, but causes heart to contract)
Part b: Explain why a small number of epinephrine molecules binding to the receptors on the surface of a liver cell
leads to the release of hundreds of millions of glucose molecules from glycogen.
a) Liver cells and heart cells posses different collections of proteins, as they are different kinds of cells. The collection
of signal receptor proteins, proteins to carry out the response, and relay proteins controls the response of a specific
cell to a signal. Liver and heart cells differ in the proteins that handle and respond to the signal, so their response to
epinephrine is specific to their cell.
b) Elaborate enzyme cascades in this signaling pathway cause signal amplification, which is a result of proteins
persisting in their active state for a long period of time. During this period of time, they process many substrate
molecules before becoming inactivating again.
LO 4.7 The student is able to refine representations to illustrate how interactions between external stimuli and gene
expression result in specialization of cells, tissues and organs.
SP 1.3: The student can refine representations and models of natural or man-made phenomena and systems in the
domain.
Explanation: Interactions between external stimuli and gene expression result in specialization and divergence of cells,
organs and tissues. In development, interactions between regulated gene expression and external stimuli, such as
temperature or nutrient levels or signal molecules, result in specialization of cells, organs and tissues. Differentiation
of the germ layers during vertebrate gastrulation is an example of one such divergence. The progression of stem cells
to terminal cells can also be explained by the interaction of stimuli and genes. Additionally, cells, organs and tissues
may change due to changes in gene expression triggered by internal cues, including regulatory proteins and growth
factors, which result in the structural and functional divergence of cells.
M.C. Question: Which of the following is an example of an outside stimulus influencing gene expression?
A) The gradual growth and development of a Himalayan rabbit in normal conditions.
B) Himalayan rabbits that carry the C gene which codes for the pigments in their fur, skin,
and eyes, and whose expression is regulated by temperature.
C) Increase in number of white Himalayan rabbits during Winter, because their fur color
blend in with the environment making them harder to capture and kill.
D)Development of two different species of Himalayan rabbits because of geographical
isolation.
Learning Log/ FRQ-style Question:
Suppose you are testing the rate of metamorphosis of a specific species of tadpole. You begin your experiment with
two randomly selected tadpoles from the same environment; Tadpole A and Tadpole B. You allow Tadpole A to
develop into a adult frog in it’s species’ ideal developmental conditions. You place Tadpole B in an environment with
increased temperature and less available resources. Is it possible for the Tadpole A and Tadpole B to both develop into
adult frogs and be about the same size and weight at the end of their developmental period? Why?
Answer Key LO 4.7
Which of the following is an example of an outside stimulus influencing gene expression?
A) The gradual growth and development of a Himalayan rabbit in normal conditions.
B) Himalayan rabbits that carry the C gene which codes for the pigments in their fur, skin,
and eyes, and whose expression is regulated by temperature.
C) Increase in number of white Himalayan rabbits during Winter, because their fur color
blend in with the environment making them harder to capture and kill.
D)Development of two different species of Himalayan rabbits because of geographical
isolation.
Suppose you are testing the rate of metamorphosis of a specific species of tadpole. You begin your
experiment with two randomly selected tadpoles from the same environment; Tadpole A and Tadpole B.
You allow Tadpole A to develop into a adult frog in it’s species’ ideal developmental conditions. You place
Tadpole B in an environment with increased temperature and less available resources. Is it possible for the
Tadpole A and Tadpole B to both develop into adult frogs and be the about same size and weight at the
end of their developmental period? Why? What would that be an example of?
Yes, it is possible for the two tadpoles to have both matured into adult frogs that are about the same
size and weight by the end of their allotted developmental periods. Tadpole B could grow into an adult
frog that is just as healthy as Tadpole A. The adverse environmental conditions could trigger a hormone
release that would allows
Tadpole B to create specialized
cells helping it survive in its
environment. That would be an
example of environmental factors
influencing gene expression.
LO 3.41: The student is able to create a representation that describes how organisms exchange information in response to internal changes and
external cues, and which can result in changes in behavior.
SP 1.1: The student can create representations and models of natural or man-made phenomena and systems in the domain.
Explanation: Organisms exchange information because cooperative behavior increases fitness of an individual and the survival of a population. The
success of information exchange is seen in the behavior of pack animals. Natural selection favors innate and learned behaviors that increase
survival. Our Brain has evolved into a master neurological center that processes signals and directs responses. Learned behaviors are behaviors that
are learned and acquired to increase reproductive success. Innate behaviors are instincts that organisms are born with that increase reproductive
success. Organisms learn avoidance behavior to things that can harm them like electric fences, poisons, or traps, thus increasing their reproductive
fitness. Animals use many different types of signals to exchange information. For example, honey bees perform certain dances to indicate which
direction food is, and birds sing to impress mates or proclaim territories. Living systems use a variety of signal behaviors that change the behavior of
other organisms and result in reproductive success. Coloration in flowers is one of these signal behaviors. Flowers with bright colors attract
pollinators which increases the reproductive success of that flower. Poison frogs use predator warnings such as bright colors which predators
understand to stay away from; increasing the reproductive success of the frog.
M.C. Question: Which of the following statements is not an example of a learned behavior?
A) Frank, Mr. Smith’s dog, tried to cross the street, but he was shocked by the electric fence. Ever since this incident, Frank has not attempted to
leave the yard.
B) James, a snake in the Amazon rainforest, watched his brother die after eating a poison dart frog. Ever since this tragedy, James has been on a
strict diet completely avoiding poison dart frogs.
C) Miranda, a Tulip from the garden, has a beautiful yellow color. Because of her color, she attracts all of the bees which increases her reproductive
success.
D) Mark, a robin in the oak tree, wanted a wife so he became the best singer in the whole village. Because of this, Mark could choose a wife of any
ladybird he wanted.
FRQ: Explain why each of the following is an advantage or disadvantage in terms of reproductive success:
1.The fight or flight response is triggered after a hungry bear begins to chase you.
2.A poison amphibian is not colorful.
3.Tulips are bright yellow flowers.
4.Birds sing hundreds of songs throughout the day.
5.Honey Bees do a waggle dance to communicate with other bees.
M.C. Question: Which of the following statements is not an example of a learned behavior?
A) Frank, Mr. Smith’s dog, tried to cross the street, but he was shocked by the electric fence. Ever since this incident, Frank has not
attempted to leave the yard.
B) James, a snake in the Amazon rainforest, watched his brother die after eating a poison dart frog. Ever since this tragedy, James has
been on a strict diet completely avoiding poison dart frogs.
C) Miranda, a Tulip from the garden, has a beautiful yellow color. Because of her color, she attracts all of the bees which increases
her reproductive success.
D) Mark, a robin in the oak tree, wanted a wife so he became the best singer in the whole village. Because of this, Mark could choose
a wife of any ladybird he wanted.
FRQ: Explain why each of the following is an advantage or disadvantage in terms of reproductive success:
1.The fight or flight response is triggered after a hungry bear begins to chase you.
2.A poison amphibian is not colorful.
3.Tulips are bright yellow flowers.
4.Birds sing hundreds of songs throughout the day.
5. Honey Bees do a waggle dance to communicate with other bees.
1. The fight or flight response when a hungry bear begins to chase you is an advantage and increases reproductive success. The
fight response would increase the amount of adrenaline and other stress hormones in you body, giving you the ability to out run
the bear.
2. This is a disadvantage and decreases reproductive success for the amphibian. Even though a poison amphibian is toxic to
anything that eats it, since it is not colorful it does not provide predator warning. Therefore, a predator would still attack, eat, and
kill the amphibian with out knowing it is toxic.
3. This is an advantage and increases reproductive success for the Tulip. Because the Tulip is bright and pretty, it will attract more
pollinators than a less attractive flower.
4. This is a reproductive advantage because the more songs birds sing, the better chance they have at attracting a mate. Singing
also provides protection for the birds by helping them proclaim and warn others of their territory.
5. Dancing is an advantage and increases reproductive success in honey bees. When a bee finds food, it communicates to its hive by
doing a waggle dance to show which direction the food is. This helps the hive eat and reproduce.
LO 4.19: The Student is able to use data analysis to refine observations and measurements
•
regarding the effect of population interactions on patterns of species distribution and
abundance.
SP 5.2: The student can refine observations and measurements based on data analysis.
Explanation: All populations are connected, so it is important to understand what connects two species or
populations, and why one effects the other. Species distribution is how a particular species is spaced out amongst
each other. These patterns are typically called random, uniform, or clumped. Species abundance is typically used
to show a correlation between two species that are correlated through either mutualism, where they both
benefit, commensalism, where one species benefits while the other is unaffected, parasitism, where one species
lives off another and harms it, and predation, where one species hunts the other. A keystone species is a species
that has a large effect on the rest of its environment based on their abundance. All of these relationships between
one species and another can be shown graphically, with time on the x axis and population abundance on the y
axis. Based on the graphs given, you can see that as the hare population rises, the lynx population rises because
they can be sustained by the large hare population, but as they kill hares, there are less left for them, so less
lynxes can be supported, so their abundance decreases. Parasitism works similarly- if the abundance of parasites
is too much, they kill the hosts, which they live off of, so they die back and as their number decreases, the hosts
can increase because there are less parasites. In a keystone species graph, the keystone species is easily identified
because if the keystone species abundance goes up or down, the entire rest of their ecosystem is effected.
M.C. Question :
Based on the graph, the relationship between the moose and wolf populations
Can best be defined as………..
A)
B)
C)
D)
Parasitism
Mutualism
Predation
Commensalism
Learning Log/FRQ
If species A’s abundancy increases as Species B’s abundancy decreases, which symbiotic
Relationship(s) do species A and B represent? Sketch a graph of the relationship and explain why it
Cannot be mutualism.
LO 4.19 answer slide
Based on the graph, the relationship between the moose and wolf populations
Can best be defined as………..
A) Parasitism
B) Mutualism
C) Predation
D) Commensalism
If species A’s abundancy increases as Species B’s abundancy decreases, which symbiotic
Relationship(s) do species A and B represent? Sketch a graph of the relationship and explain why it
Cannot be mutualism.
Species A is the predator if species B is the prey, if the relationship is predation. Species A could also be the host in a parasitic
relationship and species B would be the parasite, since the host abundancy increases as the parasite abundancy decreases.
Model taken from:
http://study.com/academy/lesson/trophiclevels-in-a-food-chain-definition-lessonquiz.html
LO 4.15 : The student is able to use visual representations to analyze situations or solve
problems qualitatively to illustrate how interactions among living systems and with
their environment result in the movement of matter and energy.
•
•
SP 1.4 : The student can use representations and models to analyze situations or solve problems qualitatively
and quantitatively.
Explanation : Energy flows through an ecosystem while matter is always conserved. The movement of matter
and energy through an ecosystem can be illustrated by models such as food webs and food chains. These
models (such as the one below) are based on primary productivity, and therefore allow scientists to understand
and make predictions about how things like global climate and atmospheric composition changes can affect
primary productivity and, by extension, entire ecosystems. They also allow scientists to predict how both biotic
and abiotic factors influence populations with the ecosystem. Further analysis of models may allow scientists
to come to a better understanding of how certain adaptations arose to make individuals more fit to obtain and
use energy and matter from the environment. Other models that may be used are the logistic growth model to
illustrate how competition for resources and other factors influence population growth and energy pyramids to
illustrate that each successive trophic level only has 10% of the total energy available at the previous level.
M.C. Question: The food web
pictured at right details the
predatory relationships between
Water birds, fish, and aquatic
producers in the Chesapeake Bay.
Only about __% of the energy
produced by primary producers
would be available to and Osprey
in this environment.
A.) 100%
`
B.) 10%
C.) 1%
D.) .1%
Learning Log/FRQ-style Question: Use
the food web pictured to explain which
individuals are the least prevalent in the
ecosystem. Use the laws of
thermodynamics in your discussion. How
would removing phytoplankton from this
food web affect the ecosystem? Which
species would be most directly affected?
What potential long-term effects could
this have if the phytoplankton continue
to be absent from the ecosystem?
Answer Key 4.15
•
•
•
•
•
A.) 100%
B.) 10%
C.) 1%
D.) .1%
Use the food web pictured to explain which individuals are the least prevalent in the ecosystem. Use
the laws of thermodynamics in your discussion. How would removing phytoplankton from this food
web affect the ecosystem? Which species would be most directly affected? What potential long-term
effects could this have if the phytoplankton continue to be absent from the ecosystem?
–
The first law of thermodynamics states that energy can be neither created nor destroyed, only
converted to another form. The second law of thermodynamics states that entropy always
increases, which means that some energy is dissipated as heat as it changes forms. Taken
together, these laws mean that energy must decrease as it moves up a food web, leaving only
10% of the previous trophic level’s total energy at the next level. Therefore, tertiary consumers
have very little energy available to them, causing them to have comparatively low population
sizes as opposed to other trophic levels. In this case, that means Osprey and Bald Eagles are the
least prevalent species in the ecosystem. Removing phytoplankton would decrease primary
productivity, decreasing the energy of the entire system. Benthic invertebrates would be most
directly affected by this change, as they feed exclusively on phytoplankton. Long-term, this
change could cause the extinction of benthic invertebrates in the ecosystem and a overall decline
in biomass of the system due to less available energy.
LO 1.27 – The student is able to
describe a scientific hypothesis about
the origin of life on Earth
SP 1.2 - The student can describe
representations and models of natural
or man-made phenomena and
systems in the domain
Sydney Fox’s
proteinoids
Miller-Urey
Experiment
FRQ: Explain a hypothesis of the
origin of life on earth. Include an
experimental design that would
support the hypothesis.
Hypotheses concerning the origin of life on Earth are all
based on information obtained in experimental
investigations. The general consensus is that conditions in
early-Earth environments were capable of producing
complex organic molecules and cell-like structures that
would be necessary for any primitive form of life to
develop. Perhaps the most well known and most important
of these investigations was the 1953 Miller-Urey
experiment. The experiment tested an earlier hypothesis by
Oparin and Haldane, which hypothesized that early Earth
environments favored reactions that produced organic
compounds from inorganic compounds. Miller and Urey
subjected gaseous water and inorganic atmospheric
molecules (like NH3, CH4, and H2) to conditions of extreme
heat and pressure (simulated lightning using electrodes).
Although not all at once, repetition of this experiment
yielded the production of all sugars, lipids, purines,
pyrimidines, all 20 amino acids: all of the monomers
necessary for organic life. The next step in the development
MC:
The 1953
experiment
resulted
in
of primitive
life isMiller-Urey
the arrangement
of the organic
molecules
into
polymers
capable
of replicating,
what?
Choose
the best
answer. storing, and
transferring
information.
1964, Dr. Sydney Fox
A) Production
of aminoInacids
conducted
an experiment
in which
organic monomers were
B) Construction
of cell-like
structures
placed onto hot sand/rocks/clay, resulting in the synthesis
C) Synthesis of all organic monomers
of proteinoids, polypeptides created abiotically.
D) Synthesis of organic polymers
E) Both A and B
Answer Key \\
LOMC:
1.27
The 1953 Miller-Urey experiment resulted in
what? Choose the best answer.
A) Production of amino acids
B) Construction of cell-like structures
C) Synthesis of all organic monomers
D) Synthesis of organic polymers
E) Both A and B
FRQ: Explain a hypothesis of the
origin of life on earth. Include an
experimental design (original or
historical) that would support the
hypothesis.
One hypothesis that attempts to explain the origin of life on Earth takes into account the
results from the Miller-Urey experiment in 1953. This experiment showed that
atmospheric gasses (like ammonia, methane, hydrogen, and water vapor), when
subjected to ideal conditions, undergo reactions that result in the production of the
organic monomers necessary for the building of polymers and the development of life on
earth. Conditions in which these reactions occur would require extreme intense heat
delivered in a very quick period of time- like lightning. Early Earth conditions that
favored these reactions would produce these monomers and subsequent reactions
under the right conditions would yield polymers and cell-like structures capable of
LO 1.13: The student is able to construct and/or justify mathematical models, diagrams or
simulations that represent processes of biological evolution.
SP 1.1: The student can create representations and models of natural or man-made phenomena
and systems in the domain.
SP 2.1: The student can justify the selection of a mathematical routine to solve problems.
•
Explanation: Scientists often use radioactive isotopes of molecules such as carbon-14 and their half-lives to accurately
estimate the age of a fossil or rock formation. A scientist would take the half life of carbon-14, 5,730 years, then measure
the amount of carbon-14 remaining in the sample to estimate how much time has passed since the death of that organism.
A scientist could also measure the allelic frequency of a gene in a population or in a community of organisms to look for
common descent from an ancestor- similarities in DNA sequences between species provides evidence of a common
ancestor.
MC Question: If when an organism dies, it has 64 grams of
carbon-14, how much time would pass before there would
be 4 grams of carbon-14 left, given that carbon-14 has a
half-life of 5730 years?
A) 5730 years
B) 22920 years
C) 17190 years
D) 34380 years
Vertebrae
Free Response
Question: Draw and
label a cladogram for
the species in this
chart that indicates
what order they
evolved in.
Bony Skeleton
Four Limbs
Amniotic Egg
Sharks
x
Finned Fish
x
x
Amphibians
x
x
x
Primates
x
x
x
x
Crocodiles
x
x
x
x
Shelled Egg
x
Answer Key LO 1.13
• Multiple Choice: the answer was B, 22920
years.
• Free Response:
Sharks
Finned Fish
Amphibians
Primates
Amniotic Egg
Four Limbs
Bony Skeleton
Vertebrae
Crocodiles
Shelled Egg
LO 3.50: The student is able to create a visual representation to describe how the vertebrate brain integrates information to produce
a response.
SP 1.1: The student can create representations and models of natural or man-made phenomena and systems in the domain.
Explanation: Sensory neurons transmit information from sensors that detect external stimuli (light, sound, touch, heat, smell, and
taste), and internal conditions (such as blood pressure, blood CO2 level, and muscle tension). This information is sent to the CNS,
where interneurons will analyze the sensory input. The nerves that connect the CNS with the rest of your body is called the PNS. A
response is achieved when the motor output leaves the CNS via motor neurons, which communicate with your effector or muscle
cells. These combined create reflexes, the bodies automatic response to stimuli. However different regions of the vertebrate brain
have different functions and pertain to things such as: vision, hearing, muscle movement, abstract thought and emotions, neurohormone production, forebrain, midbrain, and hindbrain, and your right and left cerebral hemispheres. Neurons also have: stretch,
ligand, and voltage-gated ion channels, which open and close in response to stimuli; these channels are responsible for generating
the signals of the nervous system. A stimulus strong enough to produce a depolarization that reaches the threshold triggers an action
potential. An action potential is the signal that carries information along the axon. What helps to generate an action potential is the,
Na+ and K+ ion channels that open by the depolarization of the membrane. The voltage-gated ion Na+ channels have two gates, an
activation and inactivation gate. At resting potential the activation gate is closed and the inactivation gave is open. Voltage-gated K+
channels have one gate, an activation gate and at resting potential the gate is closed. Depolarization makes the activation gates of the
Na+ channels open, while the K+ channel stays closed, and the rush of Na + in the membrane causes it to become positive. When the
inactivation gates close, the Na+ flow stops and the activation gate for the K+ channel opens; this rush of K+ into the membrane
causes the membrane to become negative.
M.C. Question:
In a neuron, why is a signal transmitted faster because of the Nodes of Ranvier
being in-between the Schwann cells?
a.) The axon surrounding the Schwann cells are insulated and the area outside of
the axon, the Nodes of Ranvier, is not and therefore is capable of generating
electrical signals.
b.) The Nodes of Ranvier are insulated and the axon surrounding the Schwann
cells are not and it is therefore capable of generating an electrical signal.
c.) Both are insulated and either can generate an electrical signal, it gets
transmitted faster because the Nodes are on the outside.
d.) It is not faster and an electrical signal is received or transmitted just as quickly
as anywhere else in the body.
Learning Log/ FRQ-Style Question:
Jimmy’s essay says that dendrites transmit information over longer distances than
axons do, and Arnold’s essay says that Axons receive signals from long distances,
which student is correct? Please explain and draw a picture to support your
answer.
Answer Key- LO 3.50
M.C. Question:
In a neuron, why is a signal transmitted faster because of the Nodes
of Ranvier being in-between the Schwann cells?
a.) The axon surrounding the Schwann cells are insulated and
the area outside of the axon, the Nodes of Ranvier, is not and
therefore is capable of generating electrical signals.
b.) The Nodes of Ranvier are insulated and the axon surrounding the
Schwann cells are not and it is therefore capable of generating an
electrical signal.
c.) Both are insulated and either can generate an electrical signal, it
gets transmitted faster because the Nodes are on the outside.
d.) It is not faster and an electrical signal is received or transmitted
just as quickly as anywhere else in the body.
Learning Log/ FRQ-Style Question:
Jimmy’s essay says that dendrites are extensions that transmit
information over longer distances than axons do, and Arnold’s essay
says that axons are extensions that receive signals from long
distances, which student is correct? Why? Please explain and draw a
picture with labels to support your answer.
Both Jimmy and Arnold are incorrect. Dendrites are widely
branched extensions that receive signals from other neurons.
Axons are very long extensions that transmit signals to other
cells, such as neurons or effector cells. Some of these cells may
reach as far as your spinal cord to the muscles in your feet. The
region that the axon joins the body cell is called the axon hillock.
(Sample Drawing):
LO 3.19 The student is ale to describe the connection between the regulation of gene expression and observed
difference between individuals in a population.
SP 7.1 : The student can connect phenomena and models across spatial and temporal scales.
Explanation: Gene regulation includes a wide range of mechanisms that ensure variability and the correct
expression of genes. Gene expression is significant in many ways such as to trigger developmental pathways,
respond to environmental stimuli, or adapt to new food sources. Any step of gene expression can be
regulated, from the start of transcription, to RNA processing, and to the translation of a protein. Gene
regulation is essential for eukaryotes as it increases the versatility and adaptability of individuals in a
population, which can be turned on or off by environmental inducers.
Multiple Choice Question: All of the steps
involved in expressing a gene are important to
eukaryotes, which of the following processes
is least important in prokaryotes (bacteria)?
A.. DNA sequencing
B. Transcription of DNA.
C. RNA processing.
D. mRNA degradation.
E. mRNA translation.
FRQ-style Question: Translation is the process in which ribosomes
create proteins by translating codons from mRNA.
List and describe three possible mutations if during
this process one or more codons were translated
incorrectly. Give an example of a disorder that result
due to one of the listed mutations.
LO 3.19 Answer key
Multiple Choice Question: All of the steps involved in expressing a gene are important to eukaryotes, which
of the following processes is least important in prokaryotes (bacteria)?
A.. DNA sequencing
B. Transcription of DNA.
C. RNA processing. – because prokaryotes do not have the necessary components to process RNA like
eukaryotes.
D. mRNA degradation.
E. mRNA translation.
FRQ-style Question: Translation is the process in which ribosomes
create proteins by translating codons from mRNA. List and describe
three possible mutations if during this process one or more codons
were translated incorrectly. Give an example of a disorder that results
due to one of the listed mutations.
Deletions are mutations in which a section of DNA is lost, or deleted.
Insertions are mutations in which extra base pairs are inserted into a new
place in the DNA. A substitution is a mutation that exchanges one base for
another. A substitution mutation could change a codon to one that encodes a
for different a amino acid and cause a change in the protein produced.
For example, sickle cell anemia is caused by a substitution in the betahemoglobin gene, which alters a single amino acid in the protein produced.