Module One, Lecture Three

Question 1

What are the key functions of Organelles? ( 4 )

Answer 1

1. Energy Production
2. Protein Synthesis
3. Waste Removal
4. Information Storage

Question 2

What are the key organelles present in a plant and animal cell? ( 4 )

Answer 2

1. Nucleus
2. Endoplasmic Reticulum
3. Golgi Apparatus
4. Mitochondrion

Question 3

What key organelle is unique to animal cells?

Answer 3

Lysosome

Question 4

What is the function of a lysosome?

Answer 4

Breaking down cellular waste and debris

Question 5

What key organelle is unique to plant cells? ( 2 )

Answer 5

1. Central Vacuole
2. Chloroplasts

Question 6

What is the function of the central vacuole? ( 3 )

Answer 6

1. Maintaining turgor pressure
2. Storing water + nutrients
3. Storing waste products

Question 7

What is the function of chloroplasts?

Answer 7

Responsible for photosynthesis; process of converting light energy into chemical energy in the form of sugars

Question 8

What covers the surface of plant and animal organelles?

Answer 8

Membranes

Question 9

How many membranes do mitochondria have?

Answer 9

Two

Question 10

What is the key component of a cell / organelle plasma membrane?

Answer 10

Phospholipid Bilayer

Question 11

What is the Phospholipid Bilayer?

Answer 11

A double membrane acting as a barrier between two aqueous compartments ( hydrophilic heads outside, hydrophobic tails imbedded within the membrane

Question 12

What is the structure of a Phospholipid?

Answer 12

Hydrophilic Head ( Glycerol and Phosphate ) with two Hydrophobic Tails ( Fatty Acids )

Question 13

What are the several types of transport across the cell membrane? ( 4 )

Answer 13

1. Diffusion
2. Facilitated Diffusion
3. Active Transport
4. Co-Transport

Question 14

What types of membrane transport are passive? ( 2 )

Answer 14

1. Diffusion
2. Facilitated Diffusion

Question 15

What types of membrane transport require energy? ( 2 )

Answer 15

1. Active Transport
2. Co-Transport

Question 16

How do the tails of Phospholipids determine the fluidity of the bilayer?

Answer 16

Saturated tails pack together increasing viscosity, while unsaturated tails prevent packing, creating fluidity

Question 17

What are some functions of Plasma Membrane Proteins? ( 3 )

Answer 17

1. Facilitating transport of molecules across the membrane
2. Act as receptors for signaling molecules
3. Enabling cell-cell recognition

Question 18

What processes are Membrane Proteins involved in? ( 5 )

Answer 18

1. Signal Transduction
2. Cell Recognition
3. Intercellular Joining
4. Linking Cytoskeleton and Extracellular Matrix
5. Membrane Transport

Question 19

What is Signal Transduction?

Answer 19

Cells receive and respond to signals, both inside and outside the cell

Question 20

What are some examples of Signal Transduction? ( 5 )

Answer 20

1. Grow
2. Divide
3. Move
4. Make something
5. Die

Question 21

What is Cell Recognition?

Answer 21

Cells identify and interact with other cells

Question 22

What is an example of Cell Recognition?

Answer 22

Immune System Response; T cells and B cells, recognise and respond to foreign pathogens

Question 23

What is Intercellular Joining?

Answer 23

Adjacent cells make contact and connect through plasma membranes

Question 24

What are some examples of Intercellular Joining? ( 3 )

Answer 24

1. Tight Junctions
2. Gap Junctions
3. Desmosomes

Question 25

What is the purpose of linking the Cytoskeleton and Extracellular Matrix?

Answer 25

Allows a cell to physically connect with protein structures outside the cell

Question 26

What is Membrane Transport?

Answer 26

Movement of molecules across biological membranes

Question 27

What is Diffusion? ( Passive Transport )

Answer 27

The movement of molecules from an area of high concentration ( of molecules ) to an area of low concentration ( of molecules )

Question 28

What is Facilitated Diffusion? ( Passive Transport )

Answer 28

Movement of hydrophilic molecules that require membrane proteins called channels and carriers

Question 29

What are Channel Proteins?

Answer 29

'Tunnels' that respond to signals to allow specific substances to go down their concentration gradient

Question 30

What are Carrier Proteins?

Answer 30

Membrane proteins that change their shape to help guide molecules down their concentration gradient

Question 31

What is Active Transport?

Answer 31

Requires transport proteins ( carriers ) that use ATP to move substances against their concentration gradient

Question 32

What is Co-Transport?

Answer 32

Indirect active transport, one substance is pumped across the membrane, and its concentration gradient is used to power the movement of a second substance against its concentration gradient