Cells and Biological Membranes

Question 1

What’s the cell theory?

Answer 1

Cells are the fundamental units of life in which all organisms are composed of.

Question 2

Describe the cell membrane.

Answer 2

It’s a selective permeable area, which allows certain cells to maintain a constant internal environment.

Question 3

Prokaryotic cells.

Answer 3

• Bacteria and Archaea
• enclosed by cell membrane
  -Nucleoid
• Cytoplasm and Ribosomes

Question 4

Special Prokaryotic Features

Answer 4

• Rigid cell wall
• Bacteria with slimy capsule of polysaccharides
• Pili, which help bacteria adhere to other cells
• Flagella protein

Question 5

What in the cell carries out biochemical functions?

Answer 5

Organelles.

Question 6

What are the organelles in an animal cell?

Answer 6

• Mitochondria
• Golgi Apparatus
• Nucleus
• Ribosomes
• Cytoplasm
• Cell Membrane
• Vacuole

Question 7

What are the organelles in a plant cell?

Answer 7

• Cell wall
• Ribosomes
• Vacuole
• Cell membrane
• Rough endoplasmic reticulum
• Nucleus
• Nucleolus
• Peroxisome
• Plasmodesmata
• Mitochondrion

Question 8

Endomembrane system

Answer 8

An interconnected system of membrane enclosed compartments. Consists of the nucleus, Golgi apparatus, vesicles, and ER. The vesicles shuttle substances between various components.

Question 9

Cytoskeleton

Answer 9

holds and maintains the cell’s shape, along with holding and moving around organelles

Question 10

What’s the endosymbiotic theory?

Answer 10

Proposes that the mitochondria and chloroplasts arose when one cell engulfed another, to which that DNA was transferred to the host.

Question 11

What’s the difference between SER and ER?

Answer 11

ER has ribosomes attached, SER does not

Question 12

What are the 3 types of cell junctions and what do they do?

Answer 12

• Tight junctions - ensure directional movement of materials
• Desmosomes - spot welds that provide mechanical stability
• Gap junctions - allows communication

Question 13

What are examples of each junction?

Answer 13

Tight junction: bladder
Desmosomes: skin
Gap junction: heart

Question 14

1 molecule = how many lipid molecules

Answer 14

25

Question 15

3 types of membrane proteins

Answer 15

Integral, peripheral, and anchored

Question 16

Describe the membrane proteins.

Answer 16

• Integral - proteins are embedded in the membrane
• Peripheral - proteins don’t penetrate the bilayer
• Anchored - membrane proteins are covalently bonded to lipids in the membrane

Question 17

Cell adhesion and recognition

Answer 17

Cells arrange themselves by this which depend on surface protein and carbs, found in sponge cells

Question 18

Define diffusion

Answer 18

the process of random equilibrium, or evenly distributed. Molecules will continue to diffuse across the membrane with no net charge

Question 19

What’s osmosis and what are the types?

Answer 19

Osmosis is the diffusion of water. Types include isotonic, hypertonic, and hypotonic.

Question 20

What’s facilitated diffusion?

Answer 20

Where polar molecules diffuse with concentration gradients, but facilitated by protein barriers or channels