Practice Exam 1 Review Qs

Question 1

An acid is a molecule that acts as a

Answer 1

proton donor

Question 2

A molecule that loses electrons during a reaction is being:

Answer 2

oxidized

Question 3

A cell membrane that is selectively permeable can regulate which substances pass through by :

Answer 3

changing its protein content

Question 4

When more than one uncharged solute (i.e., glucose and galactose) is present on both sides of the membrane, the chemical driving force acting on glucose will include:

Answer 4

the concentration of glucose only

Question 5

Homeostasis is a term which describes the process whereby the body:

Answer 5

maintains a dynamically constant internal environment

Question 6

When an enzyme’s activity is destroyed by heat or a change in pH, the enzyme is said to be:

Answer 6

denatured

Question 7

Each amino acid differs from others only by the:

Answer 7

characteristic of its R group

Question 8

Most, if not all cell to cell communication between cells is __________ in nature.

Answer 8

chemical

Question 9

Why do some normal cells fail to respond to a chemical signal?

Answer 9

Some cells lack the necessary receptors

Question 10

HCl (hydrochloric acid) is considered an acid because

Answer 10

in solution it releases its H+

Question 11

Lipophilic chemical messengers are poorly soluble in water. However, many of these lipophilic messengers are transported throughout the body. Their transport in blood (water) is facilitated by

Answer 11

carrier proteins

Question 12

True or false- A single enzyme could be simultaneously affected by both allosteric regulation and competitive regulation.

Answer 12

true

Question 13

What are the two primary extracellular fluid compartments in the body?

Answer 13

plasma and interstitial fluid

Question 14

According to the second law of thermodynamics, the amount of entropy in living systems increases without:

Answer 14

the input of energy

Question 15

Enzymes _______ the activation energy of a reaction.

Answer 15

decrease

Question 16

If blood pressure increases above normal, baroreceptors in major arteries detect the change and send signals to the brain. Certain areas of the brain then send signals to the nerves that control the heart and blood vessels to make the heart beat slower and the blood vessels increase in diameter, which in turn reduce the blood pressure

this is an example of what kind of feedback?

Answer 16

negative

Question 17

Transmembrane proteins are components of the plasma membrane that form :

Answer 17

ion channels

Question 18

Intracellular fluid is rich in:

Answer 18

proteins and potassium

Question 19

An element’s ability to bind to other elements is determined by :

Answer 19

the number of electrons in the outer shell of an atom

Question 20

What are coenzymes?

Answer 20

organic molecules derived from vitamins that function in the transfer of a chemical group

Question 21

organic molecules derived from vitamins that function in the transfer of a chemical group are called:

Answer 21

coenzymes

Question 22

Which of the following chemical messengers is lipophilic and is therefore able to cross the cell membrane?

peptides
sodium
proteins
amino acids
steroids

Answer 22

steroids

Question 23

All of the following are basic components of proteins EXCEPT

hydrogen
carbon
oxygen
nitrogen
potassium

Answer 23

potassium

Question 24

An ion widely important in intracellular signaling is due to its very low concentration in the cytosol is:

Answer 24

calcium

Question 25

In a second messenger transduction pathway, when adenylyl cyclase (aka adenylate cyclase) is activated:

Answer 25

cAMP is formed

Question 26

The greater the attractive forces between substrate and enzyme, that enzyme is said to have a higher ________ for the substrate.

Answer 26

affinity

Question 27

Which of the following molecule types is NOT a polymer?

glycogen
starch
cholesterol
triglyceride
protein
DNA

Answer 27

cholesterol
triglyceride

Question 28

All of the following are types of mediated transport EXCEPT one. Identify the exception.

primary active transport
facilitated diffusion
simple diffusion
secondary active transport

Answer 28

simple diffusion

Question 29

Molecules tend to move spontaneously _______ their chemical gradient.

Answer 29

down

Question 30

The ability of a carrier molecule to transport only one specific molecule or a group of closely related molecules is called ________.

Answer 30

specificity

Question 31

The movement of solvent molecules across a membrane from a region of low solute concentration to a region of high solute concentration is called:

Answer 31

osmosis