Chapter 1: The Cell

Question 1

What are the four tenets of the cell theory?

Answer 1

1. All living thing are made of cells
2. Cell is the functional unit of life
3. Cells only arise from pre-existing cells
4. Cells cary genetic information through DNA which is passed from parent to daughter cell.

Question 2

What is the major difference between eukaryotes and prokaryotes?

Answer 2

eukaryotic cells: nucleus enclosed in membrane

prokaryotic cells: no nucleus

Question 3

In eukaryotic cells organelles are membrane bound through a phospholipid bilayer. What is the function of this layer?

Answer 3

1. Allows for compartmentalization of functions

2. Phospholipid bilayer is a selective barrier (outer is hydrophilic, inner is hydrophobic)

Question 4

What is the structure of the nucleus like?

Answer 4

• Nucleus is surrounded by nuclear membrane.
• Nuclear pores in membrane allow for selective two-way exchange of material between cytoplasm and nucleus
• Contain a nucleolus where ribosomal RNA is made

Question 5

What is the function of the mitochondria?

Answer 5

• Power plants, important for metabolic function

- Involved in apoptosis

Question 6

What is the structure of the mitochondria like?

Answer 6

• Two layers
• Outer membrane: barrier between cytosol and mitochondria
• Inner membrane contains cristae (folds) important for increase in surface area and ETC.
• Space inside inner membrane is the matrix which is involved in ATP generation

Question 7

What are the function of Lysosomes?

Answer 7

• Breaking down many substrates

- Increase in their hydrolytic enzymes results in apoptosis

Question 8

What is the endoplasmic reticulum (ER)?

Answer 8

Interconnected membranes that continue from the nuclear envelope.

Question 9

What is the difference between smooth and rough ER?

Answer 9

Rough: contain ribosomes involved in translation of proteins
Smooth: no ribosomes, involved in lipid synthesis and detoxification

Question 10

What is the function of the Golgi Apparatus?

Answer 10

• Packing station

- Modification an distribution of cellular products

Question 11

What is the function of peroxisomes?

Answer 11

• Synthesis of phospholipids

- Breakdown of fatty acids via b-oxidation

Question 12

What is the function of the cytoskeleton?

Answer 12

• structure, maintains shape of cell

- transport of materials

Question 13

What does the cytoskeleton contain?

Answer 13

• Microfilaments
• Microtubules
• Intermediate filaments

Question 14

What are microfilaments?

Answer 14

• Solid polymerized rods of actin

- Organized into bundles and networks

Question 15

What is the function of microfilaments?

Answer 15

• Protection
• Muscle contraction
• Cytokinesis

Question 16

What are microtubules?

Answer 16

• Hollow polymers of tubular proteins

Question 17

What is the function of microtubules?

Answer 17

• Provide transport pathways for motor proteins chines and dynein carrying vesicles

Question 18

What are intermediate filaments?

Answer 18

Groups of filamentous proteins including keratin and desmin

Question 19

What is the function of intermediate filaments?

Answer 19

• Cell to cell adhesion
• Maintenance of the overall integrity o the cytoskeleton
• Rigid cell structure
• Anchor other organelles

Question 20

What are the four types of tissues?

Answer 20

1. Epithelial
2. Connective
3. Muscle
4. Nervous