Week 1 Day 2 Membrane transport, Osmosis, Cell signaling

Question 1

What are the 3 types of passive diffusion? What are their definitions?

Answer 1

• Simple diffusion: Molecules diffuse from a greater concentration to a lower concentration (estrogen)
• Active diffusion: Molecules diffuse from a lower concentration to a higher concentration (e.g. NA+)
• Diffusion via transporters: Diffuse via membrane proteins (e.g. glucose)

Question 2

What gradient will molecules always flow when going through channels?

Answer 2

-The concentration always moves down concentration gradient

Question 3

What are the 3 types of gated channels? Brief description of each?

Answer 3

• Voltage-gated ion channel: Stimulated by voltage
• Ligand-gated ion channel: Chemically gated
• Mechanically gated ion channel: Mechanic force required

Question 4

When are transporters required to be used?

Answer 4

When there are large polar molecules to diffuse or active transport

Question 5

What changes about the transporters when it shuttles solutes through it?

Answer 5

The transporter will squeeze/shuttle molecules through it and go through conformational changes.

Question 6

What are the two types of transporters?

Answer 6

-Active and passive transport

Question 7

What are passive transporters called? And, what type of port does it have?

Answer 7

• Another name for passive transport is facilitated diffusion
• It has a uniport, which means it’s moving in one direction

Question 8

What are the two types of active transport?

Answer 8

-Primary active transport & secondary active transport

Question 9

What type of port does a primary active transport have?

Answer 9

It has a uniport (moving in one direction)

Question 10

What are the two types of port that a secondary active transport has?

Answer 10

• Antiport (moving in both directions/opposite)

- Symport (gradients move in same direction)

Question 11

What are the 3 characteristics an active transporter has?

Answer 11

Specificity, competition, saturation

Question 12

In drawings, what color does green indicate?

Answer 12

-Facilitated diffusion

Question 13

In drawings, what will the color red indicate?

Answer 13

Red will mean active transport.

Question 14

What does specificity mean as it pertains to transporters?

Answer 14

-How specific the transporter protein is

Question 15

What does competition mean as it pertains to transporters?

Answer 15

The more specific, the more competitive the transporter protein is

Question 16

What does saturation mean as it pertains to transporter characteristics?

Answer 16

When all the proteins are fully saturated with ligands

Question 17

What is the example Angela used to display competitive active transporters?

Answer 17

tamoxifen, which binds to the hER alpha and hER beta receptor

Question 18

What type of energy does primary active transport use?

Answer 18

It uses ATP

Question 19

Waht type of energy does secondary active transport use? And where does it get its energy from?

Answer 19

• Uses an electrochemical gradient

- requires energy from primary active transport to initiate

Question 20

What type of active transport is the NA/K pump? Does active transporters bring cells to equilibrium or disequilibrium?

Answer 20

-primary active transport.

Question 21

For NA/K pump, describe the movement of sodium and potassium

Answer 21

3 NA+ go out of the cell and 2 K+ go in

Question 22

If a membrane is permeable, what does it let in and how does it effect net change in volume?

Answer 22

If it is permeable, it lets in lipophilic/non polar molecules are there is no net change in volume

Question 23

If a membrane is selectively permeable, what does it let in and how does it effect net change in volume?

Answer 23

If it is selectively permeable, it lets in lipophobic/polar molecules and the net water mvt be different

Question 24

What is the definition of molarity?

Answer 24

Number of molecules in a solution

Question 25

What is the definition of osmolarity?

Answer 25

Number of particles in a solution

Question 26

What is the definition of hypoosmotic?

Answer 26

Having a lower concentration of particles

Question 27

Isoosmotic definition?

Answer 27

Same # of particles in and outside cell.

Question 28

What do water molecules move through?

Answer 28

Aquaporins

Question 29

What concentration gradient will water moves towards as it pertains to osmolarity.

Answer 29

Water will move to the area with a higher ion concentration

Question 30

What is the definition of tonicity?

Answer 30

tonicity describes changes in cell volume if placed in a solution

Question 31

On average, what is the intracellular volume in a cell?

Answer 31

300mOsm

Question 32

If a solute cannot penetrate the membrane, what type of equilibrium will it reach? How does this effect volume?

Answer 32

-It’ll move towards osmotic equilibrium

Question 33

If a solute can penetrate, what type of equilibrium will it reach?

Answer 33

-It will reach dynamic equilibrium

Question 34

What happens if there is unequal tonicity?

Answer 34

Net volume will change

Question 35

In regards to tonicicty, what solution will a Hemolyzed RBC occur?>

Answer 35

hypotonic

Question 36

In regards to tonicity, what solution will crenated RBC occur?

Answer 36

They will occur in a hypertonic solution b/c there are more solutes outside of the cell, therefore the water will want to move outside of it, causing the RBC to deflate

Question 37

Does Cytosis occur in bulk or when it’s small.

Answer 37

Bulk

Question 38

What happens during endocytosis?

Answer 38

solute goes inside the cells

Question 39

What happens during enxocytosis?

Answer 39

Solutes are being pinched out of the cell

Question 40

what is a category of endocytosis?

Answer 40

Phagocytosis, which is engulfed in lygasomes.

Question 41

Definition of crine

Answer 41

Secrete

Question 42

definition of ligand

Answer 42

Ligand will bind to receptor

Question 43

Definition of cytokine

Answer 43

A chemical used for local communication between cells

Question 44

Definition of Hormone

Answer 44

A chemical used for communication secreted into blood stream

Question 45

Definition of systemic

Answer 45

All over the body

Question 46

Definition of synapse

Answer 46

A junction between two cells

Question 47

Definition of endogenous

Answer 47

A chemical signal found inside the body

Question 48

definition of exogenous

Answer 48

Chemical signal found outside of the body (likely synthetic)

Question 49

What are the two types of signals and how do they function?

Answer 49

- electrical & chemical - Electrical: changes in ion concentration - Chemical: secreted in ECF

Question 50

Definition of affinity?

Answer 50

How strong a receptor is attracted to a ligand

Question 51

How does a competitor affect affinity?

Answer 51

The competitor will bind to receptors and decrease the amount of chemical messengers that would otherwise be on the receptor

Question 52

What is a cytokine storm?

Answer 52

A cytokine storm is when there are a lot of systemic secretions that can lead to disease. Positive feedback rages out of control

Question 53

In regards to the cytokine storm, how does it work in the process of allergies?

Answer 53

Allergen -> Histamine (becomes hormone) -> diffuses into bloodstream

Question 54

How does endocrine cell communication differ from nervous system communication?

Answer 54

Endocrine secrete chemical messengers into bloodstream and have effects all over the body and nervous system achieves communication by changing ion concentration (electrical)

Question 55

Where does the chemical hormone to the receptor on the cell?

Answer 55

The chemical hormone binds inside the cell or on the cell membrane which will trigger a response

Question 56

For nervous communication, where does it bind to on the nervous cell?

Answer 56

It binds to the receptor on the cell membrane, which will trigger a response

Question 57

Which cells will receive the hormone signal?

Answer 57

Only the cells with the receptor for that particular hormone.

Question 58

What are the two types of Ligands?>

Answer 58

Lipophobic and lipophilic

Question 59

If the ligan is lipophilic and the receptor location is in cytosol (where translation occurs) what is the cellular action?

Answer 59

Protein synthesis

Question 60

If the ligand is lipophilic and the receptor location is in the nucleus, what cellular action takes place

Answer 60

Gene transcription

Question 61

If the ligand is lipophobic and the receptor location is on the membrane, what is the cellular action?

Answer 61

It will change ion permeability, or other cellular changes

Question 62

In regards to the cell, where are the 2 possible receptor locations if it is lipophilic ligand?

Answer 62

Cytosol and nucleus

Question 63

In regards to the cell, where is the receptor location for lipophobic ligands?

Answer 63

On the membrane