The Cell

Question 1

What are the four fundamental tenets of cell theory?

Answer 1

1. Cells are the basic unit of life.
2. All living things are made up of cells.
3. Cells arise from pre-existing cells.
4. Cells carry genetic information in the form of deoxyribonucleic acid (DNA).

Question 2

What is the difference between eukaryotic and prokaryotic cells?

Answer 2

Eukaryotic cells have a nucleus enclosed in a membrane, while prokaryotic cells do not.

Question 3

What is the function of the nucleus?

Answer 3

The nucleus stores genetic information and is the site of transcription.

Question 4

What is the function of the mitochondria?

Answer 4

Mitochondria are involved in ATP production and apoptosis (cell death).

Question 5

What is the function of the lysosome?

Answer 5

Lysosomes contain hydrolytic enzymes are capable of breaking down different substrates and can also be involved in apoptosis.

Question 6

What is the function of the Smooth

ER?

Answer 6

The smooth ER lacks ribosomes and is utilized for lipid synthesis and detoxification of certain drugs/poisons.

Question 7

What is the function of the Rough ER?

Answer 7

The rough ER contains ribosomes, which allows for translation of proteins.

Question 8

What is the function of the Golgi apparatus?

Answer 8

The Golgi Apparatus packages, modifies, and distributes cellular products.

Question 9

What is the function of peroxisomes?

Answer 9

Peroxisomes contain hydrogen peroxide, which is responsible for the breakdown of very long chain fatty acids via beta-oxidation.

Question 10

What are the three components of the cytoskeleton and what are they made of?

Answer 10

1. Microfilaments - made up of actin
2. Microtubules - made up of polymers
3. Intermediate filaments - made up of filamentous protein including keratin, desmin, vimentin, and lamins.

Question 11

How do the cytoskeletal structures of centrioles and flagella differ?

Answer 11

The centriole has nine triplets of microtubules with a hollow center and the flagellum has nine doublets of microtubules and two microtubules in the middle.

Question 12

What are the four types of tissue?

Answer 12

Epithelial Tissue, Connective Tissue, Muscle Tissue, and Nervous Tissue.

Question 13

What is the function of epithelial tissue?

Answer 13

It covers the body and lines its cavities. They can be involved in absorption, secretion, and sensation. They constitute the parenchyma.

Question 14

What is the function of connective tissue?

Answer 14

It supports the body and provides a framework for the epithelial cells to carry out their function. They constitute the stroma. Ex: blood, adipose, cartilage, tendons.

Question 15

How are archaea similar to bacteria and eukaryotes?

Answer 15

Archaea: Similar to bacteria as they are both single-celled organisms, they both have a circular chromosome and divide by binary fission.

Archaea: Similar to eukaryotes as they both start the process of translation with methionine, contain similar RNA polymerases, and associate their DNA with histones.

Question 16

What three shapes do bacteria commonly exist in?

Answer 16

Cocci - spherical
Bacilli - rod-shaped
Spirilli - spiral-shaped

Question 17

Bacteria that require oxygen for metabolism are called?

Answer 17

Obligate aerobes

Question 18

Bacteria that can cannot survive in oxygen-contained environment are called?

Answer 18

Obligate anerobes

Question 19

Bacteria that can toggle between aerobic metabolism and anaerobic metabolism, if need be are called?

Answer 19

Facultative anaerobes

Question 20

Bacteria that cannot do anaerobic metabolism but can tolerate anaerobic environment are called?

Answer 20

Aerotolerant anaerobes

Question 21

What are the differences between gram-positive and gram-negative cells in bacteria?

Answer 21

Gram-positive cells have a thick cell wall with a layer of peptidoglycan while gram-negative cells have a thin cell wall and contain a much smaller amount of peptidoglycan.

Question 22

What is the difference between eukaryotic flagella and prokaryotic flagella?

Answer 22

Eukaryotic flagella have nine doublets of microtubules with two microtubules in the middle.

Prokaryotic flagella are composed of a filament, a basal body, and a hook.

Question 23

What is binary fission?

Answer 23

Binary fission is a simple form of asexual reproduction (no genetic recombination) in prokaryotes.

Question 24

What are three genetic recombination processes in bacteria and how do they work?

Answer 24

Transformation - integration of foreign genetic material into the host genome.

Conjugation - sexual reproduction; involves two cells forming a conjugation bridge that facilitates the transfer of genetic material from donor male (+) to recipient female (-); allows for rapid acquisition of antibiotic resistance or virulence factors.

Transduction - Requires the use of a vector, a virus that carries genetic material from one bacterium to another.

Question 25

What are the four phases in a bacterial growth curve?

Answer 25

1. Lag Phase - bacteria are adapting to environmental conditions.
2. Exponential Phase - the rate of division increases as bacteria adapt
3. Stationary Phase - stagnant number of bacteria as resources have been reduced
4. Death phase - after bacteria have exceeded the ability of the environment to support them, they die.