Chapters 4 and 5

Question 1

You look into an electron microscope and view an unknown cell. What might you see that would tell you whether the cell is prokaryotic or eukaryotic?

Answer 1

mitochondria

Question 2

Which one of the following is the major structural component of the cell membrane?

Answer 2

phospholipid

Question 3

Prokaryotic cells use flagella for

Answer 3

propulsion

Question 4

Which of the following is a function of the plasma membrane?

Answer 4

regulate the traffic of chemicals into and out of the cell

Question 5

When mixed with water, phospholipids spontaneously form membranes because they

Answer 5

have hydrophilic phosphate groups that are attracted to water and hydrophobic fatty acids that avoid water

Question 6

The liver is involved in detoxification of many poisons and drugs. Which of the following structures is primarily involved in the process and therefore abundant in liver cells?

Answer 6

smooth ER

Question 7

What structures move proteins from the ER to the Golgi apparatus?

Answer 7

transport vesicles

Question 8

Some ribosomes are suspended in the cytosol of a cell, whereas other ribosomes

Answer 8

are attached to the rough endoplasmic reticulum

Question 9

Which of the following would be a characteristic of mitochondria that suggests that they might have evolved from free-living bacteria?

Answer 9

the mitochondria have their own DNA

Question 10

An object at rest has no…. energy, but it may have…. energy resulting from its location or structure.

Answer 10

kinetic; potential

Question 11

If the human body is 34% efficient, 66% of the food energy is converted to

Answer 11

heat

Question 12

ATP has a large amount of potential energy because of

Answer 12

the crowding of the (three) negatively charged phosphate ions

Question 13

Glucose molecules provide energy to power the swimming motion of sperm. In this example, the sperm are changing…

Answer 13

chemical energy into kinetic energy

Question 14

Diffusion is an example of

Answer 14

passive transport

Question 15

Facilitated diffusion across a biological membrane requires… and moves a substance..

Answer 15

transport proteins… without ATP

Question 16

Osmosis can be defined as…

Answer 16

the diffusion of water

Question 17

Enzymes are …. molecules which… specific chemical reactions.

Answer 17

protein…speed-up

Question 18

Active transport….

Answer 18

can move solutes from a lower concentration to a higher concentration

Question 19

Substances that plug up an enzyme’s active site are…

Answer 19

enzyme inhibitors

Question 20

What are enzymes?

Answer 20

Enzymes are proteins that catalyze chemical reactions.

Question 21

Why are enzymes important in the human body?

Answer 21

they are important because they speed up necessary reactions in the body so that we get the products that we need from those reactions at a fast enough rate, so we can actually use those products.

Question 22

What does the lactase enzyme have to do with lactose intolerance?

Answer 22

The lactase enzyme catalyzes the reaction between lactose and water, helping us digest lactose. If the lactase enzyme is not present of if there are not enough of them, lactose will go through the digestive tract without being digested. As a result, your body releases hydrogen and acids that cause discomfort whenever you eat lactose, causing lactose intolerance.

Question 23

What is the purpose of the glucose strips? What does the glucose concentration tell you?

Answer 23

The glucose test strips help us understand which sample is which by making us aware of the presence or absence of glucose in each milk sample. This also helps us determine the effect of latex on each milk sample.

Question 24

What effect does Lactex (Lactase Enzyme Solution) have on cow milk?

Answer 24

Lactex helps catalyze the reaction that breaks down the lactose in milk into glucose and galactose.