EEOB 2520 Exam 3

Gap junctions

Small channels created by connexons

Do gap junctions have ICF or ECF flow?

ICF: limited, ECF: yes

Desmosomes

Strongest connection with cadherin linkages

Do desmosomes have ICF flow?

No, they don't have channels

Do desmosomes have ECF flow?

YES

Tight junctions

Sealing of plasma membranes with claudin linkages. Like a belt around the cell

Do tight junctions have ICF or ECF flow?

NO

Transcellular

forcing movement around the cell

What is the source of energy for the cellular metabolic pathway and why?

ATP, because phosphates are HIGH ENERGY BONDS

Why do we not digest ATP?

We use it up too quickly

What are the two ways to make ATP in the cells?

Substrate level phosphorylation and oxidative phosphorylation

What is substrate level phosphorylation?

A bound phosphate to substrate is moved to ADP

What is oxidative phosphorylation

Energy input to transfer unbound phosphate to ADP

Glycolysis

Catabolism of sugar/carbs in the cytosol

What is the difference between an aerobic and anaerobic reaction?

Aerobic is dependent on oxygen whereas anaerobic is not

An aerobic reaction produces...

NADH and pyruvate

An anaerobic reaction produces...

lactate

Krebs cycle

continuation of glycolysis

What does the Krebs cycle produce?

2 ATP + CO2, NADH, and FADH2

Is the Krebs cycle dependent on O2?

It is INDIRECTLY DEPENDENT

What is the electron transport chain?

The recycling of NADH and FADH2

What does the ETC produce?

28-34 ATP, H2O with FREE RADICALS!!!

Is ETC dependent on O2?

It is DIRECTLY DEPENDENT

What do you get when you put together glycolysis, the Krebs cycle, and the ETC?

EQUATION 2!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Water is the plasma membrane

A fluid compartment barrier

What does diffusion depend on?

directly dependent on permeability, surface, and concentration gradient; inverse distance

Lipid bilayer

(P:NP:P)

Diffusion through the bilayer is ________ the gradient

WITH

Diffusion net movement

High to low concentration

Diffusion through a protein channel is

solute specific

Leak channels are...

ALWAYS open

Gated channels...

Only opened when triggered

How many different gated channels are there and what are they?

4: Chemically, voltage, mechanically, thermal

Aquaporins

a leak channel that allows water to flow into and out of the cell

Osmosis

Net diffusion of water across a membrane

Osmolarity

Total concentration of solutes in a solution

2 consequences of Osmosis

Change in cell size or osmotic pressure