Cells

Question 1

What is a cell?

Answer 1

The fundamental structural and functional unit of every organism.

Question 2

What are the two main types of cells?

Answer 2

Prokaryotic and Eukaryotic cells.

Question 3

Which domains comprise prokaryotic cells?

Answer 3

Bacteria and Archaea.

Question 4

What domain comprises eukaryotic cells?

Answer 4

Eukarya.

Question 5

List the common features of all cell types.

Answer 5

• Cell membrane
• Cytoplasm
• Genetic material (DNA)
• Ribosomes

Question 6

What is the function of the cell membrane?

Answer 6

Separates the intra-cellular environment from the extra-cellular environment.

Question 7

What is cytoplasm?

Answer 7

A semi-fluid cell interior that holds cellular organelles.

Question 8

What is the role of ribosomes in a cell?

Answer 8

Sites of protein synthesis.

Question 9

How do we distinguish between prokaryotes and eukaryotes?

Answer 9

Based on the presence or absence of a nucleus.

Question 10

Where is DNA located in eukaryotic cells?

Answer 10

In a membrane-bound organelle called the nucleus.

Question 11

Where is DNA located in prokaryotic cells?

Answer 11

In a non-membrane bound region called the nucleoid.

Question 12

What microscopy methods are used to study cells?

Answer 12

• Light microscopy
• Phase contrast microscopy
• Electron microscopy

Question 13

What is cell fractionation?

Answer 13

A biochemical method used to separate cellular components and organelles.

Question 14

What is the structure of the cell membrane?

Answer 14

A selectively-permeable double membrane (bilayer) comprised of hydrophilic phosphate heads and hydrophobic lipid tails.

Question 15

What are the main lipid components of the cell membrane?

Answer 15

• Phospholipids (75%)
• Glycolipids (5%)
• Cholesterol (20%)

Question 16

What is the fluid mosaic model?

Answer 16

A model that describes the structure of the cell membrane as a mosaic of various components.

Question 17

What are the functions of the cell membrane?

Answer 17

• Supports and maintains cell shape
• Separates intracellular and extracellular environments
• Role in cell signaling
• Controls entry and exit of substances

Question 18

Fill in the blank: Transport across the cell membrane can occur by ______.

Answer 18

Diffusion, Osmosis, Facilitated diffusion, Active transport, Endocytosis, Exocytosis.

Question 19

What distinguishes plant cells from animal cells?

Answer 19

The presence of a cell wall.

Question 20

What is the primary component of plant cell walls?

Answer 20

Cellulose.

Question 21

What is the role of the cell wall?

Answer 21

• Provides tensile strength
• Protects and supports
• Maintains cell shape
• Allows development of turgor pressure
• Prevents excessive water uptake

Question 22

What is the lamella in plant cells?

Answer 22

A pectin-rich layer between the cell walls of plant cells.

Question 23

True or False: All cell walls are equal in composition and thickness.

Answer 23

False.

Question 24

What is the significance of secondary cell walls in woody plants?

Answer 24

They provide additional support and protection.