Biology Exam 1 Lecture 2

Question 1

Emmanuelle Charpentier is known for what?

Answer 1

Crispr-Cas9 genome editing technologies

Question 2

Biological reactions that serve to break down biomolecules or foodstuffs (as opposed to assembling/synthezing them) are called:

Answer 2

catabolic

Question 3

A class of biological molecule, such as ATP, whose dissociation can release energy that enables otherwise unfavorable reactions to occur are:

Answer 3

activated carriers

Question 4

Enzymes have the following two general properties: 1) They change the equilibrium constant relating two otherwise unfavorable reactants2) They reduce the activation energy required for reactions they catalyze to occur.T or F

Answer 4

False

Question 5

2nd law of thermodynamics:

Answer 5

systems tend to move to maximum disorder or entropy

Question 6

Organisms and cells generate order through their functions. How is this order increase balanced?

Answer 6

to balance this increase in order heat is liberated to the environment

Question 7

Cells harness the energy involved in _____ from more complicated ones in foods

Answer 7

generating precursor molecules

Question 8

The origin of much of the stored energy for these processes is from:

Answer 8

photosynthesis in organisms that
become foods

Question 9

Cells obtain energy from the of organic molecules?

Answer 9

oxidation

Question 10

In order for cells to function, they must exist in a state of chemical equilibrium. T or F

Answer 10

False

Question 11

The equilibrium constant for a reaction, as in K = [AB] / [A] [B], is indicative of the strength of binding of the molecular interactions it describes. T or F

Answer 11

True

Question 12

If the free energy change, deltaG, is _____ kcal/mole, this is an energetically favorable reaction and the equilibrium constant K will be ___ .

-0.7; zero
-6.5; a negative value
-6.5; a large value
+9.0; a large value
+9.0; a small value

Answer 12

-6.5; a large value

Question 13

If the free energy change, deltaG, is ____ kcal/mole, this will be a(n)energetically unfavorable reaction and the equilibrium constant K will be ____ .

-0.7; zero
-6.5; a negative value
-6.5; a large value
+9.0; a large value
+9.0; a small value

Answer 13

+9.0; a small value

Question 14

How are energetically unfavorable reactions able to occur in cells?

Answer 14

Coupling with the dissociation of activated carriers can make them run.

Question 15

coupling reactions are

Answer 15

a solution to conversions involving unfavorable energy changes

Question 16

In the previous example of a coupled reaction where X>Y has an unfavorable energy and Y>Z has a favorable energy, in the coupled X>Y>Z reaction, DG of X>Y is changed to be favorable. T or F

Answer 16

False

Question 17

ATP:

Answer 17

1. It’s dissociation to ADP+Pi is energetically favorable.
2. It is an example of an activated carrier.
3. It can undergo hydrolysis in two different ways to provide energy to cells

Question 18

Reactions can be improved if coupled by

Answer 18

high energy activated carrier molecules

Question 19

A common strategy in pathways is to ___ reaction of the activated carrier to generate a ____ for the reaction that has more favorable reactivity

Answer 19

couple, high energy intermediate

Question 20

Reductions done by NADPH are prevalent in _____ while oxidations by NADH predominate in ____to break down foods, thus these two carriers have relatively distinct roles in cells

Answer 20

anabolic processes, catabolic processes

Question 21

Km and Vmax are terms describing?

Answer 21

Enzyme properties

Question 22

The ability of an enzyme to associate with (bind) its substrate molecule is best described by?

Answer 22

Km

Question 23

In Michaelis-Menton Relationship, what is Km? (x axis)

Answer 23

substrate concentration

Question 24

In Michaelis-Menton Relationship, what is Vmax?

Answer 24

rate of reaction

Question 25

enzymes lower activation energies which ___ the number of molecules capable of participating in a reaction

Answer 25

increases

Question 26

Enzymes called ___ can promote ______ reactions

Answer 26

kinases, phosphorylation reactions

Question 27

What are some examples of activated carriers?

Answer 27

ATP, NADH, NADPH, acetyl CoA, UDP glucose, P, E- H+, acetyl group, glucose

Question 28

Steps of enzyme cycle

Answer 28

enzyme binds with substrate at active site, the catalysis, after product separated and enzyme recycled

Question 29

Many proteins are regulated by the binding of GTP or GDP. Which form is the active state of the protein?

Answer 29

the GTP bound form

Question 30

How does phosphorylation control protein activity?

Answer 30

The phosphate group induces a change in the protein’s conformation.

Question 31

What can happen if heterochromatin spreads inappropriately into an area with active genes?

Answer 31

The active genes can become silenced.

Question 32

How does binding of GTP to a GTP-binding protein affect its activity?

Answer 32

always activates the protein

Question 33

What do histones do?

Answer 33

proteins that help package DNA into chromosomes

Question 34

What are the specialized DNA sequences that are at the ends of most eukaryotic chromosomes called?

Answer 34

telomeres

Question 35

In the living cell, histone proteins pack DNA into a repeating array of DNA–protein particles called what?

Answer 35

nucleosomes