Membranes

Question 1

What are polymers?

Answer 1

Repeated subunits constructing a molecule

Question 2

How are biological polymers formed?

Answer 2

By the removal of water (dehydration)

Question 3

Membrane phospholipids are amphipathic molecules - what does this mean?

Answer 3

Have both hydrophobic and hydrophilic parts

Question 4

What are the main functions of the cellular membrane?

Answer 4

*Compartmentalise metabolic activity
*The separation and protection of cellular components
*Provide a scaffold for signalling
*A medium for cellular energy generation

Question 5

As size of ? increases, diffusion….

Answer 5

Slows

Question 6

What is Exocytosis?

(think EXit)

Answer 6

The secretion of large molecules after a vesicle fuses with the plasma membrane

Question 7

What is Endocytosis?

(think ENter)

Answer 7

The taking in of large molecules when a vesicle is formed

Question 8

What can generate a small imbalance in ion concentrations?

Answer 8

Diffusion across semi-permeable membranes

Question 9

A membrane voltage occurs when….

Answer 9

*Immobile charges are not balanced
*Charge transport (of ions) is not fully balanced

Question 10

What is the purpose of the Nernst Equation?

Answer 10

It is used to describe the equilibrium between chemical and electrical forces on an ion

Question 11

What happens during Fluorescence Microscopy?

Answer 11

Light is absorbed by a pigment which excites electrons into a higher energy level.
The electron will drop back down to a lower energy level and release energy as light.

Question 12

What proteins do Aquoria Victoria jellyfish express?

Answer 12

Green Fluorescent Protein

Question 13

What is the GFP according to wiki?

Answer 13

A protein which exhibits green fluorescence when exposed to light int the blue UV range

Question 14

Is the endoplasmic reticulum mobile?

Answer 14

Yes, highly

Question 15

What is the endoplasmic reticulum made of?

Answer 15

Tubules and sacs and is continuous with the nuclear envelope.

Question 16

What does the smooth ER do?

Answer 16

*Lipid synthesis
*Carb metabolism
*Calcium ion storage
*Detoxification of drugs and poison

Question 17

What does the rough ER do?

Answer 17

Aids the synthesis of secretory proteins and others on bound ribosomes

Question 18

What is the Golgi Apparatus structure?

Answer 18

Stacks of flat membranous sacs

Question 19

What do the cis and trans faces of the Golgi Apparatus mean?

Answer 19

It has polarity

Question 20

What function occurs in mitochondrion?

Answer 20

Cellular Respiration

Question 21

Why is molecule transport so important?

Answer 21

For a controlled interaction between the cell and it’s environment

Question 22

What is the electrochemical gradient?

Answer 22

The net driving force for the movement of a molecule resulting from the combination of the chemical and electrical gradient

Question 23

What is energy coupling

Answer 23

Transport is coupled to the hydrolysis of ATP

Question 24

A quick summary of the sodium potassium pump?

Answer 24

1. Transporter binds 3 Na+ from inside the cell
2. Phosphorylation occurs
3. Transporter releases 3 Na+ to the outside and binds 2 K+ from outside of the cell
4. Dephosphorylation occurs
5. Transporter releases 2 K+ to the inside

Question 25

What does the sodium potassium pump generate?

Answer 25

A membrane potential

Question 26

What is an antiport?

Answer 26

When a driver ion and substrate move in the opposite direction

Question 27

What is a symport?

Answer 27

When a driver ion and substrate move in the same direction

Question 28

What is transport coupling/co-transport systems?

Answer 28

The coupling of the downward movement of one ion (the driver) to the upward movement of another solute (substrate)

Question 29

Ions channels are selective and gated, this means they can…?

Answer 29

Exert a tight control of passage