quiz 2

Question 1

What is the difference between macronutrients and micronutrients?

Answer 1

Macronutrients are required in large amounts (e.g., carbohydrates, proteins, fats), while micronutrients are needed in small amounts (e.g., vitamins, minerals).

Question 2

Name the six elements that make up the macromolecules of life

Answer 2

Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), Phosphorus (P), Sulfur (S).

Question 3

What are the macromolecules of life?

Answer 3

Carbohydrates, proteins, lipids, nucleic acids.

Question 4

Define autotroph and heterotroph.

Answer 4

Autotrophs produce their own food, while heterotrophs consume other organisms for food.

Question 5

Define phototroph and chemotroph.

Answer 5

Phototrophs obtain energy from light, while chemotrophs obtain energy from chemical compounds.

Question 6

What mechanisms do bacteria use to form ATP?

Answer 6

Substrate-level phosphorylation, oxidative phosphorylation, and photophosphorylation.

Question 7

Which ATP formation mechanism produces the most ATP in bacteria?

Answer 7

Oxidative phosphorylation.

Question 8

What are the final electron acceptors in aerobic, anaerobic, and fermentation pathways?

Answer 8

Aerobic: Oxygen (O2); Anaerobic: Inorganic molecules other than O2 (e.g., nitrate, sulfate); Fermentation: Organic molecules (e.g., pyruvate).

Question 9

What is a redox reaction?

Answer 9

A chemical reaction involving the transfer of electrons between two species.

Question 10

Compare psychrophilic, mesophilic, and thermophilic bacteria.

Answer 10

Psychrophilic thrive in cold temperatures (0-20°C), mesophilic thrive in moderate temperatures (20-45°C), and thermophilic thrive in hot temperatures (45-80°C).

Question 11

Define obligate aerobic and obligate anaerobic bacteria.

Answer 11

Obligate aerobic bacteria require oxygen to grow, while obligate anaerobic bacteria cannot tolerate oxygen.

Question 12

Define facultative aerobic and facultative anaerobic bacteria.

Answer 12

Facultative aerobic bacteria prefer oxygen but can survive without it, while facultative anaerobic bacteria prefer anaerobic conditions but can survive in oxygen.

Question 13

What are capnophiles, acidophiles, alkaliphiles, and basophiles?

Answer 13

Capnophiles require high CO2 levels, acidophiles thrive in acidic environments (pH < 5.5), alkaliphiles thrive in alkaline environments (pH > 8.5), and basophiles prefer high-pressure environments.

Question 14

What is the difference between symbiotic and nonsymbiotic relationships?

Answer 14

Symbiotic relationships involve close interactions between different species, while nonsymbiotic relationships do not involve close interactions.

Question 15

Compare parasitic, mutualistic, and commensal relationships.

Answer 15

Parasitic: One benefits, the other is harmed; Mutualistic: Both benefit; Commensal: One benefits, the other is unaffected.

Question 16

Compare antagonistic and synergistic relationships

Answer 16

Antagonistic: One organism harms another; Synergistic: Cooperative interaction for mutual benefit.

Question 17

What is binary fission?

Answer 17

A method of asexual reproduction in bacteria where a cell divides into two genetically identical cells.

Question 18

Describe the bacterial population growth curve.

Answer 18

Lag phase: Adjustment period, no division; Log phase: Rapid division and growth; Stationary phase: Nutrient depletion slows growth, cell death equals cell division; Death phase: Cells die off.

Question 19

What are characteristics of a good antimicrobial agent?

Answer 19

Selective toxicity, broad-spectrum activity, minimal side effects, non-allergenic, stability, cost-effective, and ease of use.

Question 20

Define synthetic, semisynthetic, and natural antibiotics.

Answer 20

Synthetic antibiotics: Chemically synthesized; Semisynthetic antibiotics: Chemically modified natural antibiotics; Natural antibiotics: Produced by microorganisms.

Question 21

What are the sources of antibiotics?

Answer 21

Fungi (molds) and bacteria.

Question 22

Compare bactericidal and bacteriostatic antibiotics.

Answer 22

Bactericidal antibiotics kill bacteria, while bacteriostatic antibiotics inhibit bacterial growth.

Question 23

What are the mechanisms of antibiotic actions?

Answer 23

Inhibit cell wall synthesis, protein synthesis, nucleic acid synthesis, cell membrane integrity, and metabolic pathways

Question 24

What is the lactam ring structure and how is it inhibited?

Answer 24

A key component of beta-lactam antibiotics; inhibited by beta-lactamase enzymes.

Question 25

How are antibiotics classified based on their functions?

Answer 25

Cell wall synthesis inhibitors, protein synthesis inhibitors, nucleic acid synthesis inhibitors, cell membrane disruptors, metabolic pathway inhibitors.

Question 26

Name non beta-lactam cell wall inhibitor antibiotics.

Answer 26

Vancomycin, Bacitracin

Question 27

What are the targets of macrolides and aminoglycosides?

Answer 27

Macrolides target the 50S ribosomal subunit, while aminoglycosides target the 30S ribosomal subunit.

Question 28

What is the therapeutic index?

Answer 28

The ratio of the toxic dose to the therapeutic dose of a drug; a higher index indicates greater safety.

Question 29

Describe the antibiotic disc diffusion technique

Answer 29

A method to test bacterial sensitivity to antibiotics by measuring inhibition zones around antibiotic discs.

Question 30

Compare bacterial resistance to antibiotics through mutation vs. inheritance.

Answer 30

Mutation involves changes in DNA sequence, while inheritance involves genetic transfer through reproduction.

Question 31

Compare vertical and horizontal gene transfer in bacterial resistance

Answer 31

Vertical gene transfer is from parent to offspring, while horizontal gene transfer is between bacteria (e.g., conjugation, transformation, transduction).