Life Science Assessment
Study Sheet – The Big Ideas & Essential Questions in Life Science
1. The Microscope – Why is this an important tool for the biologist and how does it work?
2. The process of enlarging the image of a specimen is called ________________________.
3. A _______________________ microscope uses two or more convex lenses. Each convex
lens bends light to make the object appear larger.
4. _____________________________ is the ability of a microscope to focus on two
separate, very close objects at the same time.
2. Cells – What is the basic unit of structure and function of all living things?
1. The organelle responsible for controlling all the activities of the cell is the
_________________________. It is the control center of the cell.
2. The organelle responsible for controlling what goes in and what goes out of the cell is the
_________________________________________.
3. The organelle responsible for turning food molecules into energy is the
__________________________________. It converts glucose and oxygen into carbon
dioxide, water and energy.
4. All living things are made of cells. The cell is the basic unit of structure and function of
all living things. All cells come from other living cells. These ideas make up
____________________________________________.
5. There are two types of cells. Cells that do not have their genetic material enclosed in a
nucleus are called _______________________________________. Bacterial cells are
prokaryotic. Cells that do have their genetic material enclosed in a nucleus are called
__________________________________. Plants, animals, fungi, and protists are
eukaryotic.
6. Prokaryotic cells like bacteria cells are ___________________________ than eukaryotic
cells like plant cells and animal cells.
3. Chemistry of Life – What are the chemical compounds necessary for life?
1. A ____________________________ is a chemical combination of two or more elements.
2. The chemical compounds that are associated with living things contain the element,
carbon. These compounds are called ____________________________ compounds.
3. The major organic compounds are carbohydrates, lipids, ________________________,
and nucleic acids.
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4. Cell Transport – How do substances get into and out of a cell?
1. The process by which molecules move from an area where they are in a higher
concentration to an area where they are in a lower concentration is called
__________________________________, a form of passive transport.
2. The diffusion of water through a selectively permeable membrane is called
_______________________________, another form of passive transport.
5. Cell Processes – What are the basic cell activities that support life?
1. The process responsible for producing most of Earth’s oxygen is
___________________________________. It uses energy from sunlight to make food.
2. The green pigment, _______________________________ is packaged in small
organelles called chloroplasts. Chlorophyll captures light energy of the sun to power the
process of photosynthesis.
3. The small holes on the undersides of leaves that allow carbon dioxide to enter are called
_______________________________________.
4. Cellular _________________________________ is the process by which cells break
down simple food molecules called glucose to release the energy they contain.
5. The processes of photosynthesis and cellular respiration are ______________________
equations and complementary equations. This means that the products of one are the raw
materials of the other.
6. The Cell Cycle and Cancer – How do cells divide and what happens when the process
goes wrong?
1. The DNA molecule is called a __________________________. It looks like a twisted
ladder or a spiral staircase.
2. Each rung of the DNA “ladder” is made up of pairs of nitrogen base pairs. There are four
nitrogen bases, adenine, thymine, guanine and cytosine. During replication, adenine pairs
up with __________________________ and cytosine pairs up with guanine. (AT-GC;
At - Grover Cleveland)
3. Prior to mitosis, all of the DNA in a cell makes copies of itself so that the two resulting
daughter cells will be identical to the parent cell. This process by which the cell copies its
DNA is called__________________________________________.
4. ________________________ is a group of over 100 diseases in which some body cells
grow and divide uncontrollably, damaging the parts of the body around them.
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7. Introduction to Genetics – How are traits passed from parent to offspring?
1. ___________________________ work was the foundation for understanding why
offspring have traits similar to those of their parents.
2. Mendel was the first scientist to interpret the data from his breeding experiments
with pea plants using the principles of probability.
______________________________ is the likelihood that a particular event will
happen.
3. ____________________________ are inherited physical characteristics that an organism has
and can pass on to its offspring through its genes.
4. A __________________ is a section of DNA or “factor” that codes for the expression
of a trait. (Actually, genes are like “recipes” for proteins. The proteins are expressed as
traits.) Mendel called them “factors.” We now call these sections of DNA that control
traits “genes.”
5. The order of DNA bases along a gene specifies the type of _______________________
that will be produced.
6. The rod-shaped structures located in the nucleus of every cell (except red blood
cells) of an organism are the chromosomes. Chromosomes are made of twisted strands
of DNA – deoxyribonucleic acid. Chromosomes are made up of _________________
joined together.
7. An allele whose trait always shows up in an organism when the allele is present is called
a ________________________________ allele
8. An allele whose trait is masked by a dominant gene is called a ____________________
allele.
9. An organism is __________________________________ for a trait if each allele for the
trait is the same
10. An organism is__________________________________ for a trait if each allele for the
trait is different.
11. A ___________________ is the offspring of parents that have different alleles for a trait.
12. The notation TT means two ________________________ alleles. The notation tt
means two recessive alleles. A pea plant that is homozygous for tall stems has the
alleles TT. It is also referred to as being homozygous dominant. A pea plant that is
homozygous for short stems has the alleles tt. It is also referred to as being
homozygous recessive.
13. The notation Tt means one dominant allele and one recessive allele. A pea plant that
is __________________________________ for tall stems has the alleles Tt.
14. An organism's ___________________________________ is its physical appearance.
In the case of the organism whose alleles are TT. The phenotype would be tall.
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15. An organism’s __________________________________ is its genetic make-up. In
the case of an organism whose alleles are TT, the genotype would be TT or
homozygous dominant.
16. A______________________________ is a chart that shows all of the possible
combinations of alleles that can result from a genetic cross.
17. The ______________________________ of inheritance states that genes are
carried from parents to offspring on chromosomes.
18. __________________________ is the process that produces sex cells a.k.a.
gametes (sperm and egg). During meiosis, the number of chromosomes is reduced
by half when chromosome pairs separate and are distributed into new
_______________________. During meiosis a cell undergoes two divisions to
reduce the number of chromosomes by half in the resulting sex cells.
19. During ________________________________, the cell uses information from a
gene on a chromosome to produce a specific protein.
20. Before protein synthesis can take place, a “messenger” must first carry the genetic
code from the DNA inside the nucleus into the cytoplasm. This genetic messenger
is called m-RNA or ____________________________ RNA.
21. A _________________________________ is any change in a gene or
chromosome. Mutations can cause a cell to produce an incorrect protein during
protein synthesis. Mutations occur when one or more nitrogen bases are substituted
for another.
8. Modern Genetics: What have scientists have learned to do with genes?
1. A _________________________________ is any difference between individuals of the
same species. Human beings show a great deal of variation.
2. Some human traits such as blood type are controlled by a single gene that has more than
two alleles. The three alleles of the single gene that controls blood type are said to
be_____________________________________.
3. Some human traits show a large number of phenotypes because the traits are controlled
by many genes. The genes act together as a group to produce a single trait.
_________________________, eye color, and height are human traits controlled by
many genes.
4. The effects of genes are often altered by the______________________________. For
example, people’s diets can affect their height.
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5. The sex chromosomes determine if a person is male or female. The combination of two X
chromosomes (XX) results in a female offspring. The combination of XY results in a
_________________ offspring.
6. The process by which a sperm cell fuses with an egg cell is called _________________
7. A ___________________________________ is a photograph of an individual’s
chromosomes. A doctor can look at the chromosomes in the karyotype to determine the
presence of genetic abnormalities.
8. An abnormal condition a person inherits through genes or chromosomes is a genetic
disorder. Genetic disorders are caused by _______________________________ during
meiosis or changes in chromosomes that are present in a parent’s sex cells.
9. _________________________________ is a genetic disorder in which an abnormal form
of hemoglobin is produced.
10. A mutation in a ___________ cell can be passed from parent to offspring.
11. Genes on the X or Y chromosomes are often called ________________ genes because
their alleles are passed from parent to child on a sex chromosome. Traits controlled by
sex-linked genes are called sex-linked traits.
12. Sex-linked traits are more common in_____________ than females. Because males have
only one X chromosomes, males are more likely than females to have a sex-linked trait
that is controlled by a recessive allele. A recessive allele on the X chromosome will
always produce the trait in a male.
13. A __________________ is a person who has one recessive allele for a trait and one
dominant allele, but does not have the trait.
14. A chart that tracks which members of a family have a particular trait is a
_______________________. They are used to trace the inheritance of traits in humans.
15. The entire DNA in one cell of an organism is called a_________________.
16. Cloning involves producing an organism that is ____________________ to the organism
from which it is produced. Cloning results in two organisms that are genetically identical.
17. During the process of evolution, change in a species over time, only traits that are
controlled by ______________________ can be acted upon by natural selection. Natural
selection is the process by which individuals that are better adapted to their environments
are more likely to survive and reproduce than other members of the same species.
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9. Evolution: How have living things have changed over time?
1. A ______________________________ is a group of closely related organisms that can
mate and produce fertile offspring. (An organism is considered fertile if it can produce
offspring.)
2. Any difference between individuals of the same species is called a
________________________________________.
3. An inherited characteristic that improves an organism’s chances to survive and reproduce
is called a(n) ________________________________________.
4. Evolution occurs by means of a process called
_________________________________________. It is process by which individuals
that are better adapted to their environments are more likely to survive and reproduce
than other members of the same species.
5. Natural selection is affected by _______________________________. The only traits
that can be acted upon by natural selection are those that are controlled by genes.
6. ___________________________________ is the change in a species over time.
7. The theory of evolution that proposes that evolution occurs steadily in tiny changes over
long periods of time is called _______________________________.
8. The theory of evolution that proposes that species evolve during short periods of rapid
change is called ____________________________________________.
9. The scientist whose name is most associated with the theory of evolution through natural
selection is ________________________________________.
10. Only traits that are__________________________________ (a.k.a controlled by genes)
can be acted upon by natural selection.
11. Scientists use fossil evidence, embryo development, homologous structures, and chemical
(protein sequences) evidence to show how and when ____________________________
occurred.
12. ___________________________ are the preserved remains or traces of organisms that
lived in the past.
13. Most fossils form when a dead organism becomes buried in sediment. Most fossils are
found in __________________________ rock.
14. Relative dating provides scientists with an ______________________ age of a fossil.
Relative dating is used to determine which of two fossils is older. The most important
evidence when using relative dating is the position of the fossil in sedimentary rock
layers.
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15. Absolute dating is used to determine the ___________________ or actual age of a fossil.
Absolute dating involves the use of radioactive elements, which have a known half-life.
The half-life of a radioactive element is the time it takes for half of the atoms in a sample
to decay. Scientists can compare the amount of the radioactive element in a sample to the
amount of the element into which it breaks down.
16. The millions of fossils that scientists have collected are called the
_________________________________________.
17. Almost all of the species preserved as fossils are now no longer living. A species is
_________________________ if no members of that species are still alive.
18. The ____________________________________________ is a kind of “calendar’ of
Earth’s history that spans more than 4.6 billion years. It is divided into smaller units
called eras and periods.
19. The Largest span of time in the Geologic Time Scale is __________________________.
20. In addition to examining fossils, scientists use similar body structures, development
before birth, DNA sequences and protein structures to determine the
____________________________________ relationships among species.
21. The more similar the ______________________________ of two species, the more
closely related they are.
22. Homologous structures are body parts that are similar in design but used for different
purposes. (Ex. horse leg, human arm, bat wing, whale flipper) Homologous structures
show that related species have inherited these structures from a
__________________________________________.
23. If two organisms look very similar during their early stages of
_____________________________________, this is evidence that the organism evolved
from a common ancestor.
24. ________________________________ are charts that show evolutionary relationships
among animals. On a branching tree, a species is more closely related to another species
on the same branch than to another species on a separate branch.
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Word Banks
Topics: Microscope, Cells, Chemistry of Life, and Cell Transport
proteins
smaller
larger
osmosis
magnification
organic
inorganic
resolution
diffusion
compound
mitochondrion
compound
eukaryotic
prokaryotic
nucleus
element
cell membrane
The Cell Theory
Topics: Cell Processes and The Cell Cycle and Cancer
cancer
respiration
chlorophyll
photosynthesis
stomata
opposite
thymine
guanine
double helix
protein synthesis
fermentation
carotene
replication
Topic: Introduction to Genetics
many genes
protein
Gregor Mendel’s
gene
traits
allele
probability
dominant
dominant
recessive
heterozygous
homozygous
phenotype
genotype
Punnett square
hybrid
heterozygous
chromosome theory
meiosis
sex cells
protein synthesis
messenger
mutation
Topic: Modern Genetics
genes
variation
environment
karyotype
identical
carrier
dimples
DNA mutations
sex-linked
males
female
height
sex cell
multiple alleles
skin color
body cell
fertilization
genome
pedigree
male
Punnett square
Topic: Evolution
development
extinct
Geologic Time Scale
fossil record
variation
exact
sedimentary
evolutionary
branching trees
gradualism
evolution
fossils
species
Charles Darwin
natural selection
punctuated equilibrium
inherited
approximate
Robert Hooke
adaptation
variation
evolution
DNA sequences
common ancestor
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