Cell Biology 218

Front 1

You treat a partially purified preparation of protein with a reagent that breaks bonds between sulfur atoms. Which level(s) of protein structure are likely to be affected the most?

Back 1

Tertiary

Quaternary

Front 2

Phospholipids:
a) are amphoteric
b) are present in membranes
c) are amphipathic
d) a and b are correct
e) b and c are correct

Back 2

b and c are correct

phospholipids are present in membranes and are AMPHIPATHIC

Front 3

Sugars polymerize by forming

Back 3

glycosidic bonds

Front 4

Is the following statement part of the Endosymbiont theory?:
The acquisition of another endosymbiont (cyanobacterium) could have converted an early heterotrophic eukaryote int o an ancestor of photosynth eukaryotes.

Back 4

Yes this theory is true.
also:
once independent microbes evolved into precursors of mitochondria and a large anaerobic heterotrophic prokaryote ingested a small aerobic prokaryote.

Front 5

Why are free ionic bonds of little importance and relatively unlikely to form in living organisms?

Back 5

Cells are composed mostly of water, which interferes with ionic bonds between free ions.

Front 6

Functional groups affect or change the properties of biochemicals because:
a) contain one or more electroneg atoms
b)they make organic molecules more polar, more water soluble and more reactive
c)may become positively or negatively charged
d)a and b
e)a, b, and c

Back 6

a, b, and c are correct

Functional groups affect or change the properties of biochemicals because of their electroneg. atoms, they make organic molecules more polar, water soluble and more reactive
and they may become pos or neg charged

Front 7

Chaperones selectively recognize and bind short stretches of exposed hydrophobic amino acids that tent to be exposed in non-native proteins but buried in proteins having native conformation T/F?

Back 7

True

Front 8

Entropy is associated with the ________ movement of particles of matter, which because they are _________ cannot accomplish a directed work process.

Back 8

random, random

Front 9

What type of protein secondary structure is characterized as being strong and flexible because of the extended structure of its backbone?

Back 9

Beta "B" pleated sheet

Front 10

The release of hydrogen ions into a solution would most likely do what to the pH?

Back 10

lower the pH because the extra H's would make it acidic.

Front 11

A hydrogen atom bound to an electronegative oxygen or nitrogen atom may lead to the formation of a weak interaction with another electronegative atom called a...?

Back 11

Hydrophobic bond

(keyword "weak" interaction with an electroneg atom.

Front 12

A spontaneous process:
a)has a +delta G
b)has a -delta G
c)necessarily proceeds very quickly
d)does not necessarily proceed very quickly
e)b and d

Back 12

b and d

spontaneous processes have a -delta G, and do not necessarily proceed very quickly

Front 13

Reactions resulting in a _____of heat _________the environment are called __________.

Back 13

loss of heat to the environment are exothermic reactions

gain of heat from the environment are endothermic reactions.

Front 14

Which of the following are true for Non-covalent bonds
a)depend of attractive forces b/t atoms w opp charge
b) weak interactions
c) can be strong due to addition of attractive forces
d)mediate dynamic interactions w/i the cell
e)all of the above

Back 14

all of the above

Front 15

Which amino acid is most likey to be found in the core of a protein?

Back 15

methionine

Front 16

The amino acids found in proteins of cells are 2 things:

Back 16

mostly L-amino acids
distinguished by their R-chains

Front 17

True or False:

The formation of internal disulfide bonds is the major interaction that drives protein folding

Back 17

FALSE

Front 18

The presence of mitochondria and chloroplasts in eukaryotic cells is thought to occur by which process?

Back 18

Endosymbiosis

Front 19

Which properties of water are an indirect result of polar covalent bonds of water molecules?

Back 19

Water has a high heat capacity

Ice has a lower density than liquid water

Front 20

What property of membranes allows interactions to take place within the membrane including the assembly of protein clusters at particular sites and the formation of specialized structures?

Back 20

membrane fluidity

Front 21

If ATP is present in relatively high amounts, what is likely to happen to the rate of glycolytic activity in that cell?

Back 21

It will slow down.

Front 22

What type of enzyme is responsible for substrate-level phosphorylation?

Back 22

Kinases

Front 23

The phosphorylation of glucose to generate glucose 6 phosphate is catalyzed by the enzyme hexokinase. This enzyme, however, is inhibited by its own product, this is an example of...?

Back 23

Feedback regulation

Front 24

Fluid filled membrane bound spherical vesicles surrounded by a single, continuous lipid bilayer, resembling a natural membrane. It is hoped that these structures loaded w/ DNA or an anticancer drug may be useful in treating cancers or some other diseases

Back 24

Liposomes