Science STAAR NotebookScience STAAR NotebookBiology - Category 1Biology - Category 1

Cell Structure and FunctionCell Structure and Function

CellsCells – the basic unit of all – the basic unit of all livingliving things. things.

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2 Different Types of Cells2 Different Types of CellsContrasting features: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 Cells2 Different Types of CellsSimilar features:Similar features:

Both cells have:

1. Cell Membrane

2. Cytoplasm

3. Ribosomes

4. Genetic Material (DNA/RNA)

STAAR QuestionSTAAR Question

Which characteristic of prokaryotic organisms Which characteristic of prokaryotic organisms makes them different from eukaryotes?makes them different from eukaryotes?

A Prokaryotes are made of cellsA Prokaryotes are made of cells

B Prokaryotes have DNAB Prokaryotes have DNA

C Prokaryotes do not have chromosomesC Prokaryotes do not have chromosomes

D Prokaryotic cells do not have membrane-D Prokaryotic cells do not have membrane-bound organellesbound organelles

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Cell PartsCell Parts Nucleus – contains Nucleus – contains DNADNA that contains the blueprint for that contains the blueprint for

making making proteinsproteins..

Ribosomes – synthesize Ribosomes – synthesize proteinsproteins by linking together by linking together amino acids with amino acids with peptidepeptide bonds. bonds.

Mitochondria - produce Mitochondria - produce energyenergy in the form of ATP for the in the form of ATP for the cell by converting oxygen and cell by converting oxygen and glucoseglucose.. Body cells that require large amounts of energy have a large Body cells that require large amounts of energy have a large

number of number of mitochondriamitochondria..

VacuoleVacuole – responsible for storing material in plant and – responsible for storing material in plant and animal cells. They are larger in plant cells. animal cells. They are larger in plant cells.

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Cell PartsCell Parts Cell membraneCell membrane – regulates what goes in and out of the – regulates what goes in and out of the

cell. cell. LipidsLipids, carbohydrates, and , carbohydrates, and proteinsproteins are found in the are found in the cell membrane.cell membrane.

Cell Wall – Cell Wall – supportsupport; found in plant and bacteria cells.; found in plant and bacteria cells.

LysosomeLysosome – contain digestive enzymes to break down – contain digestive enzymes to break down materialmaterial

Golgi BodyGolgi Body – where proteins are – where proteins are modifiedmodified by adding by adding lipids or carbohydrates and the lipids or carbohydrates and the packagedpackaged into vesicles into vesicles for transport to their final destination..for transport to their final destination..

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Cell PartsCell Parts

Cilia/Flagella – both structures give cell Cilia/Flagella – both structures give cell motilitymotility

Cilia

Flagella

STAAR QuestionSTAAR Question

What repackages proteins into forms the cell What repackages proteins into forms the cell can use, expel, or keep stored?can use, expel, or keep stored?

A LysosomesA Lysosomes

B CentriolesB Centrioles

C Golgi bodiesC Golgi bodies

D MitochondriaD Mitochondria

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Animal Cell:1.Cell membrane

2.Small vacuole

3.Mitochondria

Plant Cell1.Cell membrane &

cell wall

2.Central vacuole

3.Mitochondria & chloroplast

Transportation of MoleculesTransportation of Molecules HomeostasisHomeostasis is the maintenance of a internal and stable is the maintenance of a internal and stable

environment. environment. cell membranecell membrane maintains homeostasis for the cell by allowing maintains homeostasis for the cell by allowing

materials to pass through it.materials to pass through it.

HypertonicHypertonic solution = has more solutes solution = has more solutes Hypotonic solution = has Hypotonic solution = has littlelittle amount of solutes amount of solutes Isotonic solution = solute concentration is Isotonic solution = solute concentration is equalequal on the on the

inside and outside of membrane.inside and outside of membrane.

REMEMBER YOUR PREFIXES: REMEMBER YOUR PREFIXES: hyper = hyper = aboveabovehypo = hypo = belowbelowiso = iso = equalequal

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Transportation of MoleculesTransportation of MoleculesPassive TransportPassive Transport

No energy (ATP) requiredNo energy (ATP) required Molecules move from Molecules move from

highhigh to to lowlow concentration concentration Molecules move Molecules move withwith the the

concentration gradientconcentration gradient Examples: diffusion, Examples: diffusion,

osmosis, facilitated osmosis, facilitated diffusiondiffusion

Active TransportActive Transport Energy requiredEnergy required Molecules move from Molecules move from lowlow

to to highhigh concentration concentration Molecules move Molecules move againstagainst

the concentration the concentration gradientgradient

Examples: Examples: Sodium/Potassium Pump, Sodium/Potassium Pump, exocytosis, endocytosisexocytosis, endocytosis

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Transportation of MoleculesTransportation of Molecules OsmosisOsmosis is the diffusion of is the diffusion of waterwater into and into and

out of a cell.out of a cell.

The water is always trying to be at The water is always trying to be at equilibriumequilibrium on both sides of a on both sides of a membranemembrane..

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Will water move into or out of this cell model?

STAAR QuestionSTAAR QuestionWhich of the following functions does active Which of the following functions does active transport perform in the cell?transport perform in the cell?

A.A.Packaging proteins for export from the cellPackaging proteins for export from the cell

B.B.Distributing enzymes throughout the Distributing enzymes throughout the cytoplasmcytoplasm

C.C.Moving substances against a concentration Moving substances against a concentration gradientgradient

D.D.Equalizing the concentration of water inside Equalizing the concentration of water inside and outside the celland outside the cell

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Energy Production Energy Production To convert energy in animal and plant cells, chemical To convert energy in animal and plant cells, chemical reactions take place. Parts of a chemical reaction are:reactions take place. Parts of a chemical reaction are:

reactants products reactants products Cellular Respiration: Cellular Respiration:

Occurs in the Occurs in the mitochondriamitochondria

Animal Animal andand plant cells plant cells perform respirationperform respiration

Releases ATP energyReleases ATP energy Carbon dioxideCarbon dioxide (CO (CO22) is ) is

producedproduced WaterWater (H (H22O) is producedO) is produced

Photosynthesis:Photosynthesis: Occurs in the Occurs in the cholorplastcholorplast Plants perform Plants perform

photosynthesisphotosynthesis Absorbs solar energyAbsorbs solar energy OxygenOxygen (O (O22) is produced) is produced

GlucoseGlucose (C (C66HH1212OO66) is ) is

producedproduced

Energy ProductionEnergy Production

Photosynthesis Photosynthesis and Cellular and Cellular Respiration:Respiration: one one BIG CYCLE BIG CYCLE

of energy in the of energy in the ecosystem!ecosystem!

Glucose

STAAR QuestionSTAAR Question

The processes of photosynthesis and respiration are The processes of photosynthesis and respiration are considered opposites because-considered opposites because-

A Photosynthesis produces COA Photosynthesis produces CO22 while respiration while respiration requires COrequires CO22

B Photosynthesis happens during the day and B Photosynthesis happens during the day and respiration only occurs at nightrespiration only occurs at night

C Photosynthesis produces ATP while respiration C Photosynthesis produces ATP while respiration consumes ATPconsumes ATP

D Photosynthesis absorbs energy while respiration D Photosynthesis absorbs energy while respiration releases energyreleases energy

Cells vs. VirusesCells 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

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Surface markers

VirusVirus Viruses are Viruses are specificspecific to a host cells to a host cells

For example, HIV will only attach to For example, HIV will only attach to Helper THelper T cells cells

Viruses Viruses cannotcannot be killed by antibiotics, we can only treat the be killed by antibiotics, we can only treat the symptomssymptoms Antibiotics only attack bacteria because they have Antibiotics only attack bacteria because they have cell cell

wallswalls. Viruses do not have cell walls therefore viruses . Viruses do not have cell walls therefore viruses cannot be killed.cannot be killed.

It is recommended that people get It is recommended that people get vaccinated vaccinated so that their so that their bodies will produce antibodies to reduce bodies will produce antibodies to reduce symptomssymptoms caused caused by a virus. by a virus.

Anti-viral drugs can be developed by researching the Anti-viral drugs can be developed by researching the mechanism used by the virus to mechanism used by the virus to infectinfect cells. cells.

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Image by Adenosine

STAAR QuestionSTAAR Question

A photograph of a virus is shown below.A photograph of a virus is shown below.

The projections on the surface of this virus allow the virus to –The projections on the surface of this virus allow the virus to –

A move inside a host cellA move inside a host cell

B attach to a host cellB attach to a host cell

C control a host cellC control a host cell’’s DNAs DNA

D signal other viruses to infect a host cellD signal other viruses to infect a host cell

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Viral Reproduction2 Types:

Lytic Cycle:1. Virus attaches to

specific to host cell2. 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

Lysogenic Cycle:1. 1. Virus attaches to

specific to host cell2. Virus injects genetic

material (DNA or RNA) into host cell

3. Virus becomes dormant in host cell

4. Host cell replicates viral genetic material when it replicates its own genetic material

5. When conditions become favorable for virus, it will start the lytic cycle.

Viral ReproductionViral Reproduction

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STAAR QuestionSTAAR QuestionA person infected with HIV may not have any symptoms for a A person infected with HIV may not have any symptoms for a period of time. During this period the virus affects the body by period of time. During this period the virus affects the body by doing which of the following?doing which of the following?

A The virus produces toxins that weaken immune cells and A The virus produces toxins that weaken immune cells and prevent them from reproducing.prevent them from reproducing.

B The virus damages immune cells while using their machinery B The virus damages immune cells while using their machinery to produce copies of itself.to produce copies of itself.

C The virus uses nutrients meant for immune cells to fuel its C The virus uses nutrients meant for immune cells to fuel its own cellular respiration.own cellular respiration.

D The virus changes the identity of the nucleotides of immune D The virus changes the identity of the nucleotides of immune cells to prevent the immune system from functioning normally.cells to prevent the immune system from functioning normally.

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Cell CycleCell Cycle

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Cells not actively dividing are in the GO phase, a resting phase.

Why would a cell need to divide itself?

STAAR QuestionSTAAR Question

Which of the following must occur before Which of the following must occur before DNA replication can take place?DNA replication can take place?

A Translation of DNA into amino acidsA Translation of DNA into amino acids

B Separation of the DNA molecule into codonB Separation of the DNA molecule into codon

C Separation of the DNA between the C Separation of the DNA between the nitrogen basesnitrogen bases

D Transformation of DNA and RNAD Transformation of DNA and RNA

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Cell Cycle & MitosisCell Cycle & Mitosis

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STAAR QuestionSTAAR Question

Which phase of mitosis is occurring in the Which phase of mitosis is occurring in the cell indicated by the arrow?cell indicated by the arrow?

A prophaseA prophase C anaphaseC anaphase

B MetaphaseB Metaphase D telophaseD telophase2626

Cell Cycle DisruptionsCell Cycle Disruptions If a gene mutates, cell growth and division If a gene mutates, cell growth and division

could be could be disrupteddisrupted.. CancerCancer is a disease characterized by is a disease characterized by

uncontrolled growth of cells. uncontrolled growth of cells. These cells are not responding to the cell These cells are not responding to the cell

cyclecycle’’s s checkpointscheckpoints. . They They repeatrepeat the cell cycle continuously. the cell cycle continuously. A gene that helps prevent cancer is the A gene that helps prevent cancer is the

tumor-suppressor genetumor-suppressor gene. If this gene is . If this gene is mutated, then cancer can take over.mutated, then cancer can take over.

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STAAR QuestionSTAAR QuestionThe diagram below represents the cell cycle.The diagram below represents the cell cycle.

When cells leave the cell cycle , they exit during G1 phase and When cells leave the cell cycle , they exit during G1 phase and then enter Gthen enter G00 phase. Most normal cells can leave G phase. Most normal cells can leave G00 phase and phase and

reenter the cell cycle at G1 phase before entering S phase. reenter the cell cycle at G1 phase before entering S phase. Cancer cells are different because they cannot enter GCancer cells are different because they cannot enter G00 phase phase

and are likely to do with of the following?and are likely to do with of the following?

A Fail to complete S phaseA Fail to complete S phase C Repeat the cell cycle C Repeat the cell cycle continuouslycontinuously

B Mutate during G1 phaseB Mutate during G1 phase D Die after completing D Die after completing mitosismitosis 2828

Cell DifferentiationCell Differentiation Cell differentiation: Cell differentiation:

process of cells process of cells developing a developing a specificspecific function through the function through the expressionexpression of of different genes as different genes as they mature.they mature.

StemStem cells – cells cells – cells without a functionwithout a function

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Factors that Affect Cell Factors that Affect Cell DifferentiationDifferentiation

Gene ExpressionGene Expression:: DNADNA – genes in the DNA can be turned – genes in the DNA can be turned ““onon”” to be to be

made into a proteinmade into a protein RNA – will RNA – will copycopy the parts of the DNA needed to make the parts of the DNA needed to make

the protein needed by the organismthe protein needed by the organism Environmental Factors:Environmental Factors:

• ““triggerstriggers”” tell the RNA which parts of the DNA need to be tell the RNA which parts of the DNA need to be copiedcopied

Specialized CellsSpecialized Cells

DNA in the zygote is DNA in the zygote is passed on to new passed on to new daughterdaughter cells cells ZygoteZygote – a fertilized – a fertilized

animal cellanimal cell

Different parts of the Different parts of the DNA will be DNA will be ““expressedexpressed”” to give the new cell a to give the new cell a specific specific functionfunction

Examples: Examples: Animal and plant cellsAnimal and plant cells

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STAAR QuestionSTAAR QuestionUnicellular organisms carry out all the necessary life processes in one cell. Unicellular organisms carry out all the necessary life processes in one cell. In multicellular organisms, each cell is specialized to perform a specific In multicellular organisms, each cell is specialized to perform a specific function. How do the cells in multicellular organisms become specialized?function. How do the cells in multicellular organisms become specialized?

A Cells develop specific functions through the expression of different A Cells develop specific functions through the expression of different genes as they mature.genes as they mature.

B A single nucleus coordinates the function performed by each cell.B A single nucleus coordinates the function performed by each cell.

C The brain communicates the function required for each cell.C The brain communicates the function required for each cell.

D Each cell carries a unique set of genes. D Each cell carries a unique set of genes.

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© Patrick Haney

BiomoleculesBiomolecules

Biomolecules StructureBiomolecules StructureIdentify each biomolecule:Identify each biomolecule:

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1.

3.

2.

4.

Nucleic Acid Carbohydrate

Protein

Lipid

Biomolecules FunctionBiomolecules Function

Carbohydrates:Carbohydrates: provide provide ENERGYENERGY!! Make up cell Make up cell

membranesmembranes

Lipids:Lipids: provide provide ENERGYENERGY! !

(more than carbs)(more than carbs) Make up cell wallsMake up cell walls

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STAAR QuestionSTAAR Question

Both lipids and carbohydrates are important Both lipids and carbohydrates are important in animal cells because both-in animal cells because both-

A store energyA store energy

B contain nitrogenB contain nitrogen

C form cell wallsC form cell walls

D provide insulationD provide insulation

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