Exam 1

Question 1

Gastric juices have a pH of 1 or 2. This would indicate which of the following?

Answer 1

numerous H⁺ ions and a low pH

Question 2

What is meant by light rays being divergent?

Answer 2

It is spreading out.

Question 3

Which of the following organelles breaks down worn-out organelles?

Answer 3

lysosomes

Question 4

Which type of molecule is composed of (CH₂O) units?

Answer 4

carbohydrate

Question 5

A prokaryotic cell may possess each of the following cellular components EXCEPT:

• a cell membrane.
• a cell wall.
• ribosomes.
• a nucleus.
• flagella.

Answer 5

a nucleus.

Question 6

What is the role of the ocular lens?

Answer 6

to recreate the image in the viewer’s eye

Question 7

The total number of protons in an atom is equal to its

Answer 7

atomic number

Question 8

One of the ways smooth endoplasmic reticulum (ER) differs from rough endoplasmic reticulum is that rough ER is covered by

Answer 8

ribosomes

Question 9

What is the function of the diaphragm on a compound microscope?

Answer 9

controls the amount of light entering the condenser

Question 10

In the name Staphylococcus aureus, aureus is the

Answer 10

species

Question 11

Which of the following statements regarding competitive inhibitors is true?

• Competitive inhibitors decrease the rate of enzyme activity.
• The inhibitor will destroy the substrate.
• The inhibitor will degrade the substrate.
• The inhibitor will destroy the enzyme.

Answer 11

Competitive inhibitors decrease the rate of enzyme activity.

Question 12

Where are lipids made in the cell?

Answer 12

smooth endoplasmic reticulum (ER)

Question 13

Why are enzymes important to biological systems?

Answer 13

Enzymes decrease the amount of activation energy required for chemical reactions to occur.

Question 14

What is the type of bond holding hydrogen and oxygen atoms together in a single H₂O molecule?

Answer 14

covalent bond

Question 15

Which of the following represents the correct format for the scientific name?

Answer 15

Staphylococcus aureus

Question 16

What happens to the light rays when they hit the specimen?

Answer 16

They are reflected, refracted, or absorbed by the specimen.

Question 17

Some bacteria stain gram-positive and others stain gram-negative because of differences in the structure of their

Answer 17

cell wall

Question 18

Normal microbiota are typically found in and on all the following body locations EXCEPT the

Answer 18

blood

Question 19

The streak plate method produces pure cultures by separating individual bacterial cells from one another by

Answer 19

dragging them across a solid surface

Question 20

platform on which the slide is placed for viewing

Answer 20

stage

Question 21

A reaction that involves the transfer of electrons from one molecule to another is referred to as

Answer 21

a redox reaction

Question 22

Which are the primary molecules making up plasma membranes in cells?

Answer 22

lipids

Question 23

In a properly executed Gram stain, Gram positive organisms appear ________ while Gram negative organisms appear ________.

Answer 23

purple, red

Question 24

What do genes consist of?

Answer 24

nucleic acids

Question 25

What is the type of strong chemical bond between carbon, hydrogen, and oxygen atoms in a single organic molecule?

Answer 25

covalent bond

Question 26

Which of the following is part of the endomembrane system?

Answer 26

Golgi apparatus

Question 27

What is meant by the statement “Enzymes are biological catalysts”?

Answer 27

Enzymes speed up the chemical reactions in living cells.

Question 28

The structural framework in a cell is the

Answer 28

cytoskeleton

Question 29

The bacterial shape of the cells in the scanning electron micrograph shown in the figure would best be described as

Answer 29

bacillus

Question 30

The ocular lens is used

Answer 30

to remagnify the image formed by the objective lens

Question 31

Which of the following is the type of bond between molecules of water in a beaker of water?

Answer 31

hydrogen bond

Question 32

What enables competitive inhibitors to bind to a specific enzyme?

Answer 32

Competitive inhibitors have structures that resemble the enzyme’s substrate.

Question 33

During an oxidation reaction,

Answer 33

the donor molecule loses an electron and becomes oxidized.

Question 34

If high amounts of sulfanilamide are in the presence of an enzyme whose substrate is PABA, what outcome is expected?

Answer 34

PABA will not be catalyzed.

Question 35

The microbial process of converting sugars to alcohol is known as

Answer 35

fermentation

Question 36

A parfocal microscope

Answer 36

allows for specimens to remain in focus when changing between magnification

Question 37

The double helix is a structure associated with

Answer 37

DNA

Question 38

The term used to describe a disease-causing microorganism is

Answer 38

pathogen

Question 39

Why do all enzymatic reactions need activation energy?

Answer 39

Energy is required to disrupt a substrate’s stable electron configuration.

Question 40

Where is the genetic information of the cell stored?

Answer 40

nucleus

Question 41

How does a competitive inhibitor slow enzyme catalysis?

Answer 41

They compete with the substrate for the enzyme's active site.

Question 42

What carries instructions for making proteins from the nucleus into the cytoplasm?

Answer 42

mRNA

Question 43

Which of the following statements regarding redox reactions is true?

Answer 43

Redox reactions involve an oxidation reaction coupled with a reduction reaction.

Question 44

Why is reduction the term used to describe the gain of an electron?

Answer 44

The electron acceptor’s net charge decreases.

Question 45

What color are gram-negative bacteria at the completion of the Gram staining process?

Answer 45

pink

Question 46

Each of the following organisms would be considered a microbe EXCEPT

Answer 46

mushroom

Question 47

What type of reaction is represented by the equation below? AB → A + B

Answer 47

decomposition reaction

Question 48

Where in a cell is ATP made?

Answer 48

mitochondria

Question 49

Which of the following are the "building blocks" of proteins?

Answer 49

amino acids

Question 50

What structure acts as a selective barrier, regulating the traffic of materials into and out of the cell?

Answer 50

plasma membrane