cell biology

Question 1

the active site for an enzyme

Answer 1

involves amino acids that are brought into close proximity by extensive protein folding and many require a prosthetic group such as metal ion

Question 2

Irreversible enzyme inhibitors

Answer 2

are often toxic to cells

Question 3

An enzyme is active in the stomach of an animal but quickly loses its activity when it leaves the stomach. the example illustrates that the enzyme are

Answer 3

sensitive to changes in pH

Question 4

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

Answer 4

enzymes do not function as well at temperatures other than the optimal temperature

Question 5

list the 6 amino acids involve in the active sites of enzymes

Answer 5

Senie, aspartate, histidine, cysteine, lysine, arginine, glutamate, tyrosine

Question 6

the transfer of function groups from one molecule to another would be catalyzed by which of the following classes enzymes.?

Answer 6

transferase

Question 7

hydrolytic cleavage of one molecule would be catalyzed which of the following classes of enzymes?

Answer 7

hydrolase

Question 8

The movement of a functional group within a molecule would be catalyzed by which of the following classes of enzymes?

Answer 8

isomerase

Question 9

substrate activation may involve

Answer 9

all of these are correct

Question 10

a type of inhibitor that binds to the enzyme active site is an ____ inhibitor

Answer 10

competitive

Question 11

feedback inhibition prevent cell from

Answer 11

making products that are not needed by inhibiting the activity of enzymes in biosynthetic pathways allosterically.

Question 12

saturation can be define as

Answer 12

the inability to increase reaction velocity beyond the finite upper limit

Question 13

catalyst enhance the rate of the reaction by _____ the activation energy

Answer 13

lowering

Question 14

each od the following is a function of membrane except

Answer 14

information storage

Question 15

which of the following would be used to determine the lipid content of an isolated membrane fraction?

Answer 15

thin-layer chromatology

Question 16

the most prominent lipids in animals cell membrane are

Answer 16

phospholipids

Question 17

which of the following would be the most thermodynamically unfavorable membrane lipid activity/movement in a membrane?

Answer 17

transverse diffusion

Question 18

lipid rafts are associated with which of the following activities

Answer 18

All of the above are correct

Question 19

the correct understanding cell membrane structure is based on the _______ model

Answer 19

fluid mosiac

Question 20

FRAP has revealed that some proteins move in cell membranes much slower than they move in reconstituted liposomes. which of the following could account for limited mobility of proteins in cell plasma membranes?

Answer 20

all of the above could limit protein mobility

Question 21

Most carbon double bonds in naturally occurring unsaturated fatty acids in the _ configuration, but some are in the _ configuration, making the shape and packing of those fatty acids more like that of saturated fatty acids

Answer 21

cis, trans

Question 22

transmembrane proteins involved in detecting external chemical signals and relaying that information to the cell are known as _ proteins.

Answer 22

receptor

Question 23

substances that can readily pass through the cell membrane are chemically _ in nature

Answer 23

hydrophobic or non-polar

Question 24

buffers membrane fluidity at low temperatures and decreasing fluidity at high temperature.

Answer 24

cholesterol

Question 25

is the addition if carbohydrate side chain to protein. this process occurs in the ER and Golgi

Answer 25

glycosylation

Question 26

are most prominent in plasma membrane and play a role in cell-cell recognitions

Answer 26

glycoprotein