Sata Bio Exam 2 Squarecap

You have isolated some organisms that are unicellular with cell wall containing peptidoglycan and have flagella without any membrane enclosure. Which group do these organisms belong to?

A)

Bacteria only

B)

Archaea only

C)

Eukarya only

D)

A and B are possible

E)

None of these

A

Which of the following statements are true about origin of life on earth?

A)

Life started with alien spaceship bringing early life forms

B)

Spontaneously created by superhuman powers

C)

Water bubbles in the air compbined with minerals and formed life

D)

Basic molecules combined to make larger molecules and eventually the fist cells

E)

Alll life forms existed when the earth was formed

D

You have isolated some organisms that are unicellular with cell wall containing peptidoglycan and have flagella without any membrane enclosure. Which group do these organisms belong to?

A)

Bacteria only

B)

Archaea only

C)

Eukarya only

D)

A and B are possible

E)

None of these

A

Which of the following statements are true about origin of life on earth?

A)

Life started with alien spaceship bringing early life forms

B)

Spontaneously created by superhuman powers

C)

Water bubbles in the air compbined with minerals and formed life

D)

Basic molecules combined to make larger molecules and eventually the fist cells

E)

Alll life forms existed when the earth was formed

D

Why was RNA considered to be the first genetic material formed even before DNA?

it catalyzes reaction

Which of the following is the correct sequence of events in the origin of life?

I. Synthesis of organic monomers

II. Formation of prebiotic structures

III. Synthesis of organic polymers

IV. Formation of reproducible cells

A)

III, II, I, IV

B)

I, II, IV, III

C)

IV, III, I, II

D)

I, III, II, IV

E)

II, III, I , IV

D

A paleontologist estimates that when a particular rock formed, it contained 12 mg of the radioactive isotope potassium-40, which has a half-life of 1.26 billion years. The rock now contains 3 mg of the isotope. About how old is the rock? Enter in billions of years.

2.52

Arrange the following processes in the order in which they evolved from oldest to latest.

1. Photosynthesis

2. Respiration

3. Signaling through neurons

A)

1, 2, 3

B)

1, 3, 2

C)

3, 2, 1

D)

2, 1, 3

E)

2, 3, 1

D

Three essential requirements for an ancestral cell to grow and multiply are

1. Cell membrane to define the cell and contain reactions within

2. ___________________ make and break molecules and

3. Genetic material to reprodcuce.

metabolism

The "cell theory," in its modern form includes all of the following postulates except __________________

A)

All organisms are composed of one or more cells.

B)

Cells are the smallest living things.

C)

Cells arise only by division of a previously existing cell.

D)

All cells contain nucleus

E)

Cell is the unit of life.

D

You would be wasting your time if you were trying to use a light microscope to see_______

A)

ribosomes

B)

animal cells

C)

bacteria

D)

yeast cells

E)

chloroplasts

A

Arrange the following sequence of procedure in the proper order in this experiment done to determine proteins present in pea plants during germination.

1. load the proteins in polyacrylamide gel electrophoresis and separate them

2. break the cells by grinding them in liquid nitrogen and suspend in a buffer

3. select a suitable tissue to isolate proteins expressed only during germination

4. centrifuge the broken cells to purify proteins from other molecules

A)

1,3,2,4

B)

3,2,1,4

C)

2,4,1,3

D)

3,2,4,1

E)

2,4,3,1

D

In agarose gel electrophoresis, DNA or RNA fragments migrate towards ___________ end of the gel plate because of their____________.

A)

the neutral..... charge

B)

the anode ..... size

C)

the cathode ..... charge

D)

the anode ..... charge

E)

the neutral ..... size

D

You are working for CDC and investigating a toxic E. coli contamination.

Which method would be useful to identify toxic E. coli?

Hint: Bacterial toxins are usually proteins encoded by specific genes.

gel electrophoresis

Lipids and carbohydrates do not have any charges associated with them, making it difficult to separate them by gel electrophoresis. What methods are good for separating such molecules?

centrifuge

If the dimension of a cube shape cell is 1 µm, the ratio of cell surface area to volume would be _____ to 1.

6

If the dimension of a cube shape cell is 10 µm, the ratio of cell surface area to volume would be _____ to 1.

0.6

Which organisms will have linear chromosomes with histone proteins bound to their DNA?

A)

Bacteria only

B)

Archaea only

C)

Eukarya only

D)

A and B are possible

E)

None of these

C

Tasmanian tigers are extinct because of hunting by humans but the close relative Tasmanian devils are still alive and thriving well.

If you were to use an adult cell's nucleus with intact DNA from a Tasmanian tiger to replace the nucleus of a Tasmanian devil's egg cell and make it produce to a new organism in a surrogate Tasmanian devils womb, what kind of organism will it make?

A)

Tasmanian Tiger

B)

Tasmanian Devil

C)

Hybrid with 50% of both organisms

D)

Mostly Tasmanian Tiger

E)

Mostly Tasmanian Devil

D

How many different types of ribosomes are found in a plant cell?

3

When the pH was increased from 5 to 7 in an in vitro experiment, these structures purified from animal cells stopped digesting their contents. What are these structures?

A)

smooth ER

B)

lysosomes

C)

nucleus

D)

mitochondria

E)

Golgi vesicles

B

Read this paragraph and answer the question.

CYP3A4 is a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases that catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids, and other lipids components.

The CYP3A4 protein localizes to the endoplasmic reticulum, and its expression is induced by glucocorticoidsand some pharmacological agents. Cytochrome P450 enzymes metabolize approximately 60% of prescribed drugs, with CYP3A4 responsible for about half of this metabolism;,[5] substrates include acetaminophen, codeine, ciclosporin (cyclosporin), diazepam, and erythromycin. The enzyme also metabolizes some steroids and carcinogens.[6] Most drugs undergo deactivation by CYP3A4, either directly or by facilitated excretionfrom the body.

If someone is addictted to Oxycontin (modified codine), shown below,

which of the following enzymes and structures would try to detoxify them?

A)

cytochrome p450, lysosomes

B)

cytochrome p450, rough ER

C)

lysoszyme, mitochondrion

D)

cytochrome p450, smooth ER

E)

lysozyme, smooth ER

D

Which of the following pathway is the most probable pathway for secretory proteins that is glycosylated along the way?

A)

ER → Vesicle → nucleus → lysosomes → plasma membrane

B)

Nucleus → Smooth ER → Golgi apparatus → plasma membrane

C)

Golgi Apparatus → vesicles → lysosomes → plasma membrane

D)

Ribosomes → lysosomes → Golgi apparatus → plasma membrane

E)

Rough ER → vesicles → Golgi apparatus → plasma membrane

E

Fresh water protists such as paramecium maintain homeostasis of its salt concentration by pumping water out of the cell. Which of the following structures would serve this purpose?

A)

Large central vacuole

B)

Small central vacuole

C)

Proton pump

D)

Contractile vacuole

E)

Food vesicle

D

How many cellular structures the rough endoplasmic reticulum is associated with?

6

Which of the following structures are important for providing energy for cytoplasmic functions in a plant?

A)

microtubules

B)

chloroplast

C)

mitochondrion

D)

lysosome

E)

nucleus

C

We need to consume essential amino acids in our diet because we do not have ______________ that make essential amino acids.

A)

Mitochondria

B)

Ribosomes

C)

Lysosomes

D)

Plastids

E)

Glyoxysomes

D

How does the double membrane structure of mitochondrion help in its function to make ATP?

A)

Stopping any molecules to go through mitochondrion

B)

Allowing only small molecules to go through the double membrane

C)

Controlling only polar molecules to go through

D)

Maintaining conditions within and between the two membranes to allow ATP synthesis

E)

Allowing only non-polar molecules to go through them

D

Both mitochondria and chloroplast are maternally inherited. Some plants develop resistance to atrazine herbicide through a mutation of a gene located in the chloroplast. If male plants without any such herbicide resistance are crossed with an atrazine resistant female plant, what will be the resistance level of offspring plants?

A)

All offspring will be resistant.

B)

None of them will be resistant.

C)

Half will be resistant and half susceptible.

D)

Only the female plants will be resistant and not the male plants.

E)

Only the male plants will be resistant and not the female.

A

Which of the following action facilitated by microfilaments, a plant cell will not be able to do?

A)

Movement of chromosomes during cell division

B)

Transport of vesicles along microtubules

C)

Cleavage furrow (pinching in middle of cell) formation during cell division

D)

Cytoplasmic streaming of chloroplasts

E)

Synthesis of carbohydrates and essential amino acids

C

Give an example of how cytoskeletal elements helps in sexual reproduction of animals.

cleavage furrow

Which of the following is the correct sequence of plant cell structural layers, beginning with the cytoplasmic side and progressing outward? It may help to draw two adjacent plant cells and the cell walls to answer this question.

A)

Plasma membrane, middle lamella, secondary wall, primary wall

B)

Middle lamella, primary wall, secondary wall, plasma membrane,

C)

Plasma membrane, secondary wall, primary wall, middle lamella

D)

Primary wall, middle lamella, secondary wall, plasma membrane,

E)

Plasma membrane, secondary wall, middle lamella, primary wall

C

If you were to genetically engineer a papaya plant that will resist fungal disease, you would like to express high levels of the enzyme _____________ that will degrade the fungal cell wall.

A)

proteinase

B)

phosphatase

C)

chitinase

D)

cellulase

E)

lysozyme

C

Which of the following structures are important for maintaining water pressure and movement of water in a tall plant?

A)

Desmosomes

B)

Plasma membrane

C)

Plasmodesmata

D)

Tight junctions

E)

Cell wall

E

Bacteria and fungi can degrade wood because they can make the enzyme _________________________.

cellulase

The digestive tract lining contains epithelial (outer lining) cells that do not allow food particles to randomly go inside the body except through specific proteins on their cell membrane. Which of the following structure blocks random diffusion of food particles between epithelial cells?

A)

Desmosomes

B)

Gap junctions

C)

Plasmodesmata

D)

Tight junctions

E)

Cell wall

D

While you swim in the pool, you do not absorbe water and swell because the skin has_________________________.

tight junctions

Which of the following molecules will rapidly diffuse through lipid part of cell membrane?

A)

Water

B)

Glucose

C)

Steroid

D)

Salt

E)

small protein

C

Which of the following components of cell membrane affects the selective permeability?

A)

Phospholipids

B)

Proteins

C)

Carbohydrates

D)

Both A and B

E)

A, B and C

D

Which of the following will affect the fluidity of a cell membrane?

A)

Sterols

B)

oligosaccharides

C)

saturation levels of fatty acid side chains

D)

peripheral proteins

E)

phosphate head groups

C

Which of the following would result when freshwater plant cells are placed in sea water?

A)

Absorb water, swell and burst.

B)

Become turgid with the cell wall bulging out.

C)

Become flaccid with stable cytoplasm inside cell wall.

D)

Get plasmolyzed with water from cytoplasm leaking out.

E)

The plant cell wall collapses and cell ruptures.

D

Use the following information and Table to answer the question.

Five dialysis bags (synthetic membrane that do not allow glucose to go through) with various contents were placed in beakers with aqueous solutions. The bags were weighed before and after placing in the beaker for 24 hours.

Bag

Dialysis Bag Content

Beaker content

A

0.5 M glucose

Water

B

0.75 M glucose

0.5 M glucose

C

1.0 M glucose

Water

D

0.75 M glucose

1.0 M glucose

E

Water

1.0 M Glucose

Which bag will lose the most amount of weight (net) after 24 hours incubation in the respective solutions?

A)

B)

C)

D)

E)

E

Which of the following will be able to cross a dialysis membrane with a pore size of 100 daltons (AMU) and not through biological membrane?

A)

CO2

B)

NaCl

C)

Starch

D)

DNA

E)

O2

B

When the cell's membrane potential reaches +30 mV, what should happen to restore the membrane potential to become -70 mV?

A)

Allow K+ to leave cell and Na+ to come in

B)

Transport Cl- to outside

C)

Transport both Na+ and K+ inside

D)

Transport K+ to outside

D

Which of the following is/are highly specific mechanism(s) of cell transport?

A)

Active transport

B)

Receptor mediated endocytosis

C)

Simple diffusion

D)

Both A and B

E)

All A, B and C

D

Refer to the ECG chart segment shown above and choose the point which represents the depolarized state that makes the action potential.

A)

P

B)

Q

C)

R

D)

S

E)

T

C

Which of the following cells can perform phagocytosis?

A)

Bacteria

B)

White blood cells

C)

Plant cells

D)

Fungal cells

E)

Skin cells

B

Animal viruses infect specific host cells and do not cross host range. This is because viruses are allowed inside cells through _______________________

A)

Phagocytosis

B)

Pinocytosis

C)

Receptor mediated endocytosis

D)

Facilitated diffusion

E)

Exocytosis.

C

A high level of LDL (Low density lipoprotein) - cholesterol found in blood (serum) is a major risk factor for heart disease. Such high cholesterol may be due to diet or genetic make-up. Which of the following may be the reason for a vegan to have high levels of serum LDL-cholesterol?

A)

Synthesis of cholesterol by liver

B)

Lack of membrane receptors to uptake cholesterol

C)

Consumption of cholesterol in the vegan diet

D)

A and B

E)

A and C

D

Which of the following affects all others in the cell communication process?

A)

Signal reception

B)

Change of receptor shape

C)

Signal transduction

D)

Transcription and translation

E)

Physical and physiological response

A

Which of the following molecules are the most essential for cell communication?

A)

DNA

B)

RNA

C)

Proteins

D)

Lipids

E)

Polysaccharides

C

Read the following passage and answer the question.

Activation of N-methyl-D-aspartate (NMDA) receptors in rat cerebellum leads to the release of endothelium-derived relaxing factor, now identified as nitric oxide (NO), a stimulator of soluble guanylate cyclase. L-NG-mono-methylarginine (L-NMMA), which blocks NO synthesis from L-arginine in several tissues, including a crude synaptosomal preparation from brain, inhibited the elevation of cyclic GMP induced by NMDA in rat cerebellar slices. D-NMMA was ineffective. L-Arginine, but not its D enantiomer, augmented the response to NMDA and reversed the inhibition by L-NMMA. The results indicate that stimulation of NMDA receptors results in the activation of the enzyme which catalyzes the formation of NO from L-arginine.

What is the second messenger in this signalling process?

A)

NMDA

B)

L-Arignine

C)

NO

D)

D-NMMA

E)

L_NMMA

C

Phosphorylation of a series of proteins ("phosphorylation cascade") during signal transduction _____.

A)

causes target proteins to change their shape and therefore their activity.

B)

brings a conformational change to the cell's DNA.

C)

cannot occur in yeasts because they lack protein phosphatases.

D)

always results in enzyme inactivation inside the target cell.

E)

causes binding of a hormone to a cytosol receptor.

A

What is the most active cell communication process happening in your body right now for you to see, hear and sense the surroundings?

synaptic

Read the following passage and answer the question.

Activation of N-methyl-D-aspartate (NMDA) receptors in rat cerebellum leads to the release of endothelium-derived relaxing factor, now identified as nitric oxide (NO), a stimulator of soluble guanylate cyclase. L-NG-mono-methylarginine (L-NMMA), which blocks NO synthesis from L-arginine in several tissues, including a crude synaptosomal preparation from brain, inhibited the elevation of cyclic GMP induced by NMDA in rat cerebellar slices. D-NMMA was ineffective. L-Arginine, but not its D enantiomer, augmented the response to NMDA and reversed the inhibition by L-NMMA. The results indicate that stimulation of NMDA receptors results in the activation of the enzyme which catalyzes the formation of NO from L-arginine.

What is the second messenger in this signalling process?

A)

NMDA

B)

L-Arignine

C)

NO

D)

D-NMMA

E)

L_NMMA