Cell and Molecular Biology Exam 2

enzyme

binds substrates in a matter that facilitates the formation of product

carboxypeptidase A

which of the following is an enzyme

enzymes don't function as well at temperatures other than the optimal temperatures

a sick person often has a fever, which can inhibit the growth of the bacteria because

hydrolases

the equation AB+H2O ----> A+B would be catalyzed by which of the following classes of enzymes

an allosteric inhibitor

binds at the regulatory site

a competitive inhibitor

cannot be processed as a substrate by the enzyme

a prosthetic group in an enzyme

is located in the reaction center, assists in catalysis

increasing the number of molecules with energy high enough to undergo the reaction

an increase in temperature activates chemical reactions by

catalyst

enhances the rate of the reaction

irreversible inhibition

Aspirin binds to the prostaglandin synthetase and permanently stops its ability to produce prostaglandin. This is an example of

bioluminescent

Fireflies have the ability to convert the energy in ATP to light. Which of the following types of work is performed by the firefly?

concentration

nerve impulses travel along the neurons by the opening of channels that allow sodium ions to flow inward, followed by an outward flow of potassium ions. In order to ensure that the impulse may be produced at any time, sodium is actively transported out of the cell, and potassium is transported into the cell by Na+K pump

is a tenet of the first law of thermodynamics

the statement, the total amount of energy in the universe is constant

the reaction is exergonic

negative free energy change indicates that

require oxygen to produce energy

Aerobic refers to what property of chemotrophs?

stomata

CO2 generally enters the plant through pores called

central semifluid region

in chloroplast the stroma, is the

carbon fixation, CO2 is reduced to organic sugars, occurs in the chloroplast stroma, a carbon assimilation process

which statement accurately describes the calvin cycle

stroma of the chloroplast

the calvin cycle occurs in the

ribulose biphosphate caroxylase/ oxygenase (rubisco)

In the Calvin cycle, the enzyme that catalyzes the capture of carbon dioxide and the formation of 3-phosphoglycerate is

cytoplasm

Biosynthesis of sucrose occurs in the ____

catabolic

breakdown of glucose to pyruvate by a cell is an example of

charge repulsion

negatively charged phosphates of ATP influence on another by

2

gross output of ATP from glycolysis is 4, where as the net output of ATP is

without oxygen, pyruvate is being convered to lactic acid

during strenuous exercise, you may notice your muscles burn

reduction reactions are endergonic, oxidation reactions are exergonic

energy in the cell can be stored by accumulating reduced compounds because

using phosphate to break the bond between monomers

phosphate cleavage of starch or glycogen polymers involves

ATP, NADH, pyruvate

The products of glycolysis are

acetyl CoA and used in aerobic respiration

in aerobic conditions, pyruvate generated during glycolysis is converted to

liver

Gluconeogenesis occurs in the

Acetyl CoA

Is not a production of the TCA cycle-

oxygen

Would not be used as a final electron acceptor in anaerobic respiration

0 mV

resting potential of a particular nerve is -66 V. Depolarization of the membrane will shift the membrane potential toward

1 msec

based on graph, what period of time sodium channels start to inactivate

D

graph above, what point in the action potential does repolarization

not depolarize

graph above, at the same time that stimulus was introduced, a drug that specifically inhibits sodium channels was added to the system. Effect this would have is that the membrane would

sensory, interneuron, and motor innervating the extensor muscle

the knee-jerk reflex circuit includes activation of the following neurons

can be different part of the channel molecule

structure of an ion channel, the gate and the selectivity filter

2

your record amplitudes of 0,2,6,8 pA in a single channel experiment. How many channels are in this patch

activation of sodium channels, channels,

activation of voltage-gated potassium channels, inactivation of sodium channels,

closing of voltage-gated K+ channels

the order of events in an action potential is

electrical is faster and bidirectional

the main differences between electrical and chemical synapse are

synaptic, paracrine, endocrine signaling

signaling distance is increasing in the following order

ER calcium pump, plasma membrane calcium pump, and calcium/sodium exchanger

transport systems involved in maintaining low calcium ion concentration in the cytoplasm are

smooth muscle relaxation

nitric oxide signaling is involved in regulation of

passive transport

Not a function of cytoskeleton

correct sequence of microtubule assembly

dimers, oligomers, protofilaments, closing of microtubule, elongating microtubule

anchoring site for mRNA during transcription

Not a function associated with the cytoskeleton

striated muscle

has light (I-bands) and dark bands (A-bands).

what happens when muscle contracts

I band gets smaller, H zones get smaller, Z lines get closer together

sacroplasmic reticulum

in relaxed muscle, calcium is found in high concentration in the

enzyme

_____activity may be regulated by several means

feed-back inhibition

when glucose is converted to glucose-6-phosphate by hexokinase, the accumulation of glucose-6-phosphate inhibits the reaction

non-competitive inhibition

a foreign substance is added to the reaction in part a (glucose is converted to glucose-6-phosphate by hexokinase, the accumulation of glucose-6-phosphate inhibits the reaction). The substance binds to the hexokinase and prevents its ability to catalyze the reaction

allosteric inhibition

an in-active form of an enzyme becomes active after being phosphorylated