Download Science TAKS Notebook Objective 2

Science STAAR Notebook
Biology - Category 1
Cell Structure and Function
Cells – the basic unit of all living things.
1
2 Different Types of Cells
Contrasting features:

Prokaryotic




Doesn’t have a
nucleus
Simple=doesn’t
contain membrane
bound organelles
Usually unicellular
organisms
Examples: bacteria

Eukaryotic



Contains a nucleus
with a nuclear
membrane
Complex=contains
membrane bound
organelles
Examples: animal and
plant cells
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2 Different Types of Cells
Similar features:
Both cells have:
1. Cell Membrane
2. Cytoplasm
3. Ribosomes
4. Genetic Material
(DNA/RNA)
STAAR Question
Which characteristic of prokaryotic
organisms makes them different from
eukaryotes?
A Prokaryotes are made of cells
B Prokaryotes have DNA
C Prokaryotes do not have chromosomes
D Prokaryotic cells do not have membranebound organelles
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Cell Parts

Nucleus – contains DNA that contains the
blueprint for making proteins.

Ribosomes – synthesize proteins by linking
together amino acids with peptide bonds.

Mitochondria - produce energy in the form of
ATP for the cell by converting oxygen and
glucose.


Body cells that require large amounts of energy have
a large number of mitochondria.
Vacuole – responsible for storing material in
plant and animal cells. They are larger in plant
cells.
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Cell Parts

Cell membrane – regulates what goes in and out
of the cell. Lipids, carbohydrates, and proteins
are found in the cell membrane.

Cell Wall – support; found in plant and bacteria
cells.

Lysosome – contain digestive enzymes to break
down material

Golgi Body – where proteins are modified by
adding lipids or carbohydrates and the packaged
into vesicles for transport to their final
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destination..
Cell Parts
Cilia/Flagella – both structures give cell
motility
Flagella
Cilia
STAAR Question
What repackages proteins into forms the cell
can use, expel, or keep stored?
A Lysosomes
B Centrioles
C Golgi bodies
D Mitochondria
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Animal Cell:
1. Cell membrane
2. Small vacuole
3. Mitochondria
Plant Cell
1. Cell membrane &
cell wall
2. Central vacuole
3. Mitochondria &
chloroplast
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Transportation of Molecules

Homeostasis is the maintenance of a internal and stable
environment.




cell membrane maintains homeostasis for the cell by allowing
materials to pass through it.
Hypertonic solution = has more solutes
Hypotonic solution = has little amount of solutes
Isotonic solution = solute concentration is equal on the
inside and outside of membrane.
REMEMBER YOUR PREFIXES:
hyper = above
hypo = below
iso = equal
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Transportation of Molecules
Passive Transport




No energy (ATP) required
Molecules move from
high to low concentration
Molecules move with the
concentration gradient
Examples: diffusion,
osmosis, facilitated
diffusion
Active Transport
 Energy required
 Molecules move from low
to high concentration
 Molecules move against
the concentration
gradient
 Examples:
Sodium/Potassium Pump,
exocytosis, endocytosis
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Transportation of Molecules
 Osmosis
is the diffusion of water into and
out of a cell.
 The
water is always trying to be at
equilibrium on both sides of a membrane.
Will water move into
or out of this cell
model?
12
STAAR Question
Which of the following functions does active
transport perform in the cell?
A.Packaging proteins for export from the cell
B.Distributing enzymes throughout the
cytoplasm
C.Moving substances against a
concentration gradient
D.Equalizing the concentration of water
inside and outside the cell
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Energy Production
To convert energy in animal and plant cells, chemical
reactions take place. Parts of a chemical reaction are:
reactants
products

Cellular Respiration:





Occurs in the
mitochondria
Animal and plant cells
perform respiration
Releases ATP energy
Carbon dioxide (CO2)
is produced
Water (H2O) is
produced

Photosynthesis:





Occurs in the
cholorplast
Plants perform
photosynthesis
Absorbs solar energy
Oxygen (O2) is
produced
Glucose (C6H12O6) is
produced
Energy Production
 Photosynthesis
and Cellular
Respiration:
Glucose

one BIG CYCLE
of energy in the
ecosystem!
STAAR Question
The processes of photosynthesis and respiration
are considered opposites becauseA Photosynthesis produces CO2 while respiration
requires CO2
B Photosynthesis happens during the day and
respiration only occurs at night
C Photosynthesis produces ATP while respiration
consumes ATP
D Photosynthesis absorbs energy while respiration
releases energy
Cells vs. Viruses

Cells







Contain genetic
material
Can reproduce
themselves
Smallest unit of life
Perform many forms of
metabolism
Contain specialized
organelles
Ex: skin cell
Viruses







Not considered
living
Contain genetic material
Can’t reproduce on their
own
Needs a living
cell to reproduce
Doesn’t have a
metabolism
Doesn’t contain
specialized organelles
Ex: HIV and influenza
Surface
markers
17
Virus

Viruses are specific to a host cells
 For example, HIV will only attach to
Helper T cells
Image by Adenosine

Viruses cannot be killed by antibiotics, we can only treat
the symptoms
 Antibiotics only attack bacteria because they have cell
walls. Viruses do not have cell walls therefore viruses
cannot be killed.
 It is recommended that people get vaccinated so that
their bodies will produce antibodies to reduce
symptoms caused by a virus.

Anti-viral drugs can be developed by researching the
mechanism used by the virus to infect cells.
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STAAR Question
A photograph of a virus is shown below.
The projections on the surface of this virus allow the virus to –
A move inside a host cell
B attach to a host cell
C control a host cell’s DNA
D signal other viruses to infect a host cell
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Viral Reproduction
2 Types:
Lytic Cycle:
1. Virus attaches to
specific to host cell
2. Virus injects genetic
material (DNA or RNA)
into host cell
3. Host cell replicates
genetic material
4. New virus parts
assemble inside host
cell
5. Virus leave cell,
damaging the cell

1.
2.
3.
4.
5.
Lysogenic Cycle:
1. Virus attaches to
specific to host cell
Virus injects genetic
material (DNA or RNA)
into host cell
Virus becomes dormant
in host cell
Host cell replicates viral
genetic material when it
replicates its own
genetic material
When conditions
become favorable for
virus, it will start the lytic
cycle.
Viral Reproduction
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STAAR Question
A person infected with HIV may not have any symptoms for
a period of time. During this period the virus affects the
body by doing which of the following?
A The virus produces toxins that weaken immune cells and
prevent them from reproducing.
B The virus damages immune cells while using their
machinery to produce copies of itself.
C The virus uses nutrients meant for immune cells to fuel
its own cellular respiration.
D The virus changes the identity of the nucleotides of
immune cells to prevent the immune system from
functioning normally.
22
Cell Cycle
Why would
a cell need
to divide
itself?
Cells not
actively
dividing are
in the GO
phase, a
resting
phase.
23
STAAR Question
Which of the following must occur before
DNA replication can take place?
A Translation of DNA into amino acids
B Separation of the DNA molecule into
codon
C Separation of the DNA between the
nitrogen bases
D Transformation of DNA and RNA
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Cell Cycle & Mitosis
25
STAAR Question
Which phase of mitosis is occurring in the
cell indicated by the arrow?
A prophase
C anaphase
B Metaphase
D telophase
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Cell Cycle Disruptions
 If
a gene mutates, cell growth and division
could be disrupted.
 Cancer is a disease characterized by
uncontrolled growth of cells.
 These cells are not responding to the cell
cycle’s checkpoints.
 They repeat the cell cycle continuously.
 A gene that helps prevent cancer is the
tumor-suppressor gene. If this gene is
mutated, then cancer can take over.
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STAAR Question
The diagram below represents the cell cycle.
When cells leave the cell cycle , they exit during G1 phase and
then enter G0 phase. Most normal cells can leave G0 phase and
reenter the cell cycle at G1 phase before entering S phase.
Cancer cells are different because they cannot enter G0 phase
and are likely to do with of the following?
A Fail to complete S phase
B Mutate during G1 phase
C Repeat the cell cycle
continuously
D Die after completing
mitosis
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Cell Differentiation
 Cell
differentiation:
process of cells
developing a
specific function
through the
expression of
different genes as
they mature.
 Stem cells – cells
without a function
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Factors that Affect Cell
Differentiation

Gene Expression:



DNA – genes in the DNA can be turned “on” to be
made into a protein
RNA – will copy the parts of the DNA needed to make
the protein needed by the organism
Environmental Factors:
• “triggers” tell the RNA which parts of the DNA need to be
copied
Specialized Cells


DNA in the zygote is
passed on to new
daughter cells


Examples: Animal and plant cells
Zygote – a fertilized
animal cell
Different parts of the
DNA will be
“expressed” to give
the new cell a specific
function
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STAAR Question
Unicellular organisms carry out all the necessary life processes
in one cell. In multicellular organisms, each cell is specialized to
perform a specific function. How do the cells in multicellular
organisms become specialized?
A Cells develop specific functions through the expression of
different genes as they mature.
B A single nucleus coordinates the function performed by each
cell.
C The brain communicates the function required for each cell.
D Each cell carries a unique set of genes.
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Biomolecules
Remember:
© Patrick Haney
Biomolecules Structure
Identify each biomolecule:
1.
4.
Nucleic Acid
2.
Carbohydrate
3.
Protein
Lipid
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Biomolecules Function

Carbohydrates:



provide ENERGY!
Make up cell
membranes
Lipids:



Nucleic Acids:


Stores information
Proteins:

Functions vary:
provide ENERGY!
(more than carbs)
Make up cell walls
35
STAAR Question
Both lipids and carbohydrates are important
in animal cells because bothA store energy
B contain nitrogen
C form cell walls
D provide insulation
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