Biology
TAKS Review
TAKS covers a lot
of Biology…
for more help with
Biology after today,
check out AM/PM and
lunch tutoring!
Let’s start with
Ecology…
Food Chain
A food chain shows
the flow of energy
through the
organisms in a
community
What terms would
you use to describe
each step in the
food chain?
Food Chain
Quaternary
Consumer
Tertiary Consumer
Secondary Consumer
Primary Consumer
Producer
Food Chain
The arrows show
the direction of
ENERGY FLOW!
It does not matter which way
food chain is placed on
paper…arrows always go in
direction of energy flow!
F
o
r
e
x
Energy still goes from the
plant to the grasshopper,
then mouse, then snake,
then eagle…
follow the arrows!
Food Chain
Only 10% of the energy
at one level is passed on
to the next energy level.
LEAST
Energy
The producers contain
the MOST energy
contains the LEAST
energy.
90% of energy is lost as heat
MOST
Energy
Food Webs
Food Webs are lots of food chains
linked together…use the same
terms to describe organisms!
Food Webs
Which organisms
are the producers?
Food Webs
Which organisms are the
primary consumers?
Food Webs
Which organisms are
herbivores?
Food Webs
Which organisms are
carnivores?
Food Webs
Which organism is an
omnivore?
Food Webs
What’s missing?!?
Decomposers!
(bacteria or fungi)
Let’s practice…
Try questions 1-13 on
your review packet
Now let’s talk
about relationships
between organisms…
Mutualism
• This type of relationship benefits
both organisms involved.
• Example: A bee and a flower.
It’s good for the bee because
the bee needs the pollen to
make honey. It’s good for the
flower because the bee will
pollinate the flower, and a
flower needs to be pollinated
for reproduction.
Mutualism
Parasitism
• This type of relationship benefits one
of the organisms and harms the other
organism involved in the relationship.
• Example: A flea on a cat. A leech
on an animal
It is good for the flea because
the flea gets its nourishment
from the cat. It is bad for the
cat because the flea bites the
cat and opens the skin for
possible infection, and the cat
also loses blood.
Commensalism
• In this type of relationship, one organism
benefits while the other organism is
neither harmed nor benefited.
• Example: Barnacle
on a shell.
It is good for the
barnacle because it
needs somewhere to
live, but it doesn’t harm
the shell.
Predation
• In this type of relationship, one organism
captures another organism for food.
• Example:
A lion eats
a zebra
Let’s practice…
Try questions 14-20 on
your review packet
Now let’s talk about
CELLS…
All cells have…
1. Genetic Material…DNA in chromosomes
2. Cell membrane
3. Cytoplasm – fluid inside the cell
4. Ribosomes – organelles that make proteins
There are two main types of cells….
1. Prokaryotic Cells
- ONLY Bacteria
- do NOT have a nucleus or any other
organelles surrounded by membranes
2. Eukaryotic Cells
- found in animals, plants, fungi, and protists
- DO have a nucleus and other organelles
surrounded by membranes
There are two main types of cells….
NOT living
Prokaryotic cells are
much smaller than
eukaryotic cells.
Viruses are even
smaller and NOT
made up of cells.
They are considered
to be nonliving.
They reproduce
inside a host cell.
Prokaryotic Cell
(no nucleus)
Eukaryotic Cell
(has nucleus)
There are two types of bacteria….
1. Kingdom Eubacteria
- no nucleus, typical bacteria, have cell wall
made up of chemical called peptidoglycan
- Ex. Streptococcus pneumoniae is a bacterium that
causes pneumonia…can be treated with antibiotics
2. Kingdom Archaebacteria
- no nucleus, live in extreme
environments, cell walls lack peptidoglycan
- Ex. bacteria that live in polar ice caps or
undersea volcano vents
Four Eukaryotic Kingdoms….
1. Kingdom Animalia
Heterotrophs!
- eukaryotic, multicellular
- no cell wall, no chloroplasts, no central vacuole
2. Kingdom Plantae
Autotrophs!
- eukaryotic, multicellular
- cells do have cell wall made of cellulose
surrounding cell membrane
- have chloroplast for photosynthesis
- also have central vacuole for water storage
Four Eukaryotic Kingdoms….
3. Kingdom Fungi
Remember that fungi are
one of our types of
decomposers!
- eukaryotic, multicellular
- no chloroplasts, no central vacuole
- cell wall made of chitin
4. Kingdom Protista
- eukaryotic and mostly UNICELLULAR
- some have cell walls, some do photosynthesis
- move with cilia, flagella, pseudopodia
- very DIVERSE kingdom!
What type of
cell is this?
How do you
know?
Animal Cell
No cell wall
No chloroplast
No central vacuole
What type of
cell is this?
How do you
know?
Prokaryotic
(Bacterial) Cell
DNA NOT in a nucleus!
No nucleus
Ribosomes, but no
other organelles
What type of
cell is this?
How do you
know?
Protist Cell
Eukaryotic
Unicellular organism
Use cilia to move
What type of
cell is this?
How do you
know?
Protist Cell
Eukaryotic
Unicellular organism
Use psuedopodia to move
What type of
cell is this?
How do you
know?
Plant Cell
Cell Wall
Chloroplast
Central vacuole
What type of
cell is this?
How do you
know?
Protist Cell
Eukaryotic
Unicellular organism
Use flagella to move
Let’s practice…
Try questions 21-30 on
your review packet
What do all of those
cell organelles do?
Controls what goes
in and out of cell
Selectively permeable to
maintain homeostasis
Cell
Membrane
Nucleus
Contains DNA,
control center of
the cell
Powerhouse of
the cell – makes
ATP in cellular
respiration
Mitochondria
TIME OUT!
Aerobic Cellular Respiration Reminder:
Cells convert the stored chemical energy
in glucose (a sugar) to chemical energy
stored in ATP using oxygen…produces
carbon dioxide and water.
This occurs in the mitochondria!
C6H12O6 + O2
CO2 + H20
Ribosomes
tiny dots
Ribosomes make
proteins…they
are in ALL cells
Endoplasmic
Reticulum
Transportation
system to move
proteins in cell
“Post Office” of the cell –
modifies and packages
proteins to be secreted
from the cell
Golgi Apparatus
contain enzymes that
recycle cellular material
Lysosomes
Cell Wall
Provides support
for plant cell
Site for photosynthesis
Makes sugar using
sunlight energy
Chloroplast
TIME OUT!
Photosynthesis Reminder:
Cells convert solar energy to glucose
(a sugar) using water
and carbon
dioxide…produces oxygen.
This occurs in the chloroplasts!
It’s the opposite equation of respiration!
CCO
+ 20O2
6H12
+6 H
2 O
H220
C6HCO
12O26 ++ O
Stores
water
Central
Vacuole
Let’s practice…
Try questions 31-39 on
your review packet
Now it’s time for DNA
and protein synthesis…
Structure of DNA
(Deoxyribonucleic Acid)
Twisted ladder shape…
a double helix
Made up of molecules
called nucleotides
Inherited from
gametes of parents
Each nucleotide is
made up of a sugar
(deoxyribose), a
phosphate group,
and a nitrogen base.
Nucleotide
A
T
There are 4 nucleotides:
Adenine (A)
C
Cytosine (C)
G
G
C
Guanine (G)
Thymine (T)
T
A
Adenine pairs with Thymine and
Cytosine pairs with Guanine
Mistakes in DNA
Mistakes in replicating DNA are
called mutations.
Only mutations that are made in
gametes (sex cells…sperm and eggs) are
passed on to offspring.
When a cell wants to make a protein…
Step 1 – TRANSCRIPTION:
Cells makes a strand of messenger
RNA from the DNA template
If nitrogen base in DNA is CGATGTACGGTAA
what is sequence of nitrogen bases in mRNA?
When a cell wants to make a protein…
Remember!
Step 1 – TRANSCRIPTION:
RNA contains the nitrogen base
Cells makes
a strandofofTHYMINE
messenger
URACIL
(U) instead
(T)
RNA from the DNA template
So when the DNA base is ADENINE,
If nitrogen base in DNA is CGATGTACGGTAA
the mRNA that pairs
what is sequence of nitrogen bases in mRNA?
with that base will be URACIL
When a cell wants to make a protein…
Step 1 – TRANSCRIPTION:
Cells makes a strand of messenger
RNA from the DNA template
If nitrogen base in DNA is CGATGTACGGTAA
what is sequence of nitrogen bases in mRNA?
mRNA = GCUACAUGCCAUU
When a cell wants to make a protein…
Step 2 – TRANSLATION:
Ribosomes read mRNA and make a
protein by linking together amino acids
Transfer RNA (tRNA) molecules bring the
correct amino acid to the ribosome
based on the mRNA code
Protein
tRNA
Ribosome
Universal Codon Chart
Let’s make sure you
know how to read this
chart, so that you can
translate mRNA chains
into amino acid chains!
Universal Codon Chart
Try to translate this
sequence of mRNA
codons…
AUG CCG GAG UUA
AUG?
= methionine
CCG?
= proline
GAG?
= glutamate
UUA?
= leucine
So the mRNA strand of
AUG CCG GAG UUA codes for
the amino acid sequence…
methionine – proline – glutamate - leucine
Let’s practice…
Try questions 40-50 on
your review packet
Now it’s time for
Punnett squares…
Punnett Squares
Gametes are cells
that fuse with
other cells during
fertilization.
Punnett Square Terminology
• Homozygous
• Dominant
• Recessive
• Heterozygous
• Phenotype
• Genotype
Genotype vs. Phenotype
Dominant vs. Recessive
Example
In pea plants, spherical seeds (S) are dominant to
dented seeds (s). In a genetic cross of two plants
that are heterozygous for the seed shape trait, what
fraction of the offspring should have spherical
seeds?
Gametes from
Parents
S
s
S
s
SS
Ss
Question: What is the
chance of having a
homozygous recessive
plant?
ss
Question: What is the
chance of having
spherical seeds?
sS
Lets finish up with
human systems…
Human Systems
Human Systems
Skeletal System:
Role – provide support and protection for the body.
Major Organs - Bones, cartilage, tendons and
ligaments
Human Systems
Muscular System:
Role – provide movement for the body.
Major Organs - skeletal and smooth muscles.
Human Systems
Circulatory System:
Role – transport
nutrients, gases (such as
oxygen and CO2),
hormones and wastes
through the body.
Major Organs - heart,
blood vessels, and blood.
Human Systems
Nervous System:
Role – to relay electrical
signals through the body
Major Organs - Brain,
spinal cord and peripheral
nerves.
Human Systems
Respiratory System:
Role – to provide gas
exchange between the
blood and the environment.
Major Organs - Nose,
trachea and lungs
Human Systems
Digestive System:
Role – to breakdown and
absorb nutrients
Major Organs - Mouth,
esophagus, stomach,
small and large intestines.
Human Systems
Excretory System:
Role – to filter out cellular
wastes, toxins and excess
water or nutrients from the
circulatory system.
Major Organs - Kidneys,
ureters, bladder and urethra
Human Systems
Endocrine System:
Role – to relay chemical
messages through the body
Major Organs hypothalamus, pituitary,
thyroid, pancreas and adrenal
glands.
Human Systems
Reproductive System:
Role – to manufacture cells that allow
reproduction
Major Organs - ovaries, uterus, testes,
seminal vesicles and sperm.
Human Systems
Lymphatic/Immune
System:
Role – to destroy and
remove invading microbes
and viruses from the body
Major Organs - Lymph,
lymph nodes and vessels,
white blood cells, T- and Bcells.
Human Systems
Integumentary System:
Role – to protect the body
and act as a receptor.
Major Organs - skin
Let’s practice…
Try questions 51-70 on
your review packet
Remember that
tutoring is
available if you
would like more
help preparing for
the TAKS!
THE END