Module 7

Question 1

what are the functions of the plasma membrance

Answer 1

a physical barrier, selective permeability, communicate, signaling, and electrochemical gradient

Question 2

what is the function of a physical barrier

Answer 2

separating the intra and extra-cellular fluid compartments and activities

Question 3

what is the function of selective permeability

Answer 3

to decide what goes in the cell and when

Question 4

what is the function of communication

Answer 4

to allow cell-to-cell recognition

Question 5

what is the function of signaling

Answer 5

cells respond to or send out signals to modify other cells for maintaining homeostasis

Question 6

what is the function of electrochemical gradient

Answer 6

excitability

Question 7

what is the ‘model’ name describing plasma membranes

Answer 7

the fluid mosaic

Question 8

what is the term for inside the cell

Answer 8

intracellular

Question 9

what is the term for outside the cell

Answer 9

extracellular or interstitial (between cells)

Question 10

why don’t we call the plasma membrane a cell wall

Answer 10

Cell wall is only found in plants where plasma membrane is found in all living organisms including plants

Question 11

what are the lipid types found in the plasma membranes

Answer 11

phospholipids, glycocalyx, cholesterol, and lipid rafts

Question 12

what is the function of phospholipids

Answer 12

structural

Question 13

what is the function of glycocalyx

Answer 13

identify self from self, decorating the outside, how you are recognized

Question 14

what is the function of cholesterol

Answer 14

protects the cell and keeps it fluid when it wants to freeze

Question 15

what is the function of lipid rafts

Answer 15

holds proteins

Question 16

what are the functions of membrane proteins

Answer 16

transport, receptors, structure, and enzymes catalyze cellular responses to various signals

Question 17

what are transports

Answer 17

channels and transporters

Question 18

what are receptors

Answer 18

responding to extracellular chemical signals

Question 19

what are structures

Answer 19

stability, intracellular cytoskeleton ‘anchors’ - intercellular connections

Question 20

what are the functions of membrane carbohydrates

Answer 20

cell-to-cell recognition and interaction, identification and communication

Question 21

what protein function would permit Na+ ions to enter the cell

Answer 21

channel transporter

Question 22

what would respond to a hormone signal

Answer 22

receptor

Question 23

what kind of membrane modification increases surface area

Answer 23

microvilli

Question 24

what is microvilli

Answer 24

extends the surface and increases cell membrane surface area

Question 25

what kind of membrane modification sweeps mucus over the cell surface

Answer 25

cilia

Question 26

what is cilia

Answer 26

sweeps the materials off the cell surface, keeps it clean

Question 27

what are the three types of cell junction

Answer 27

tight junction, desmosomes, gap junctions

Question 28

what is the function of tight junction

Answer 28

keeps stuff from slipping between the cells

Question 29

what is the function of desmosomes

Answer 29

distributing tension to keep cells from tearing apart

Question 30

what is the function of gap junctions

Answer 30

allowing chemicals to flow from cell to cell, communicate

Question 31

what is the difference between semi and selective permeability

Answer 31

semi- some things are capable to trans-membrane movement and others aren't selective- the 'permission to access' is selective to meet the needs of the cell, depend on what the cell needs

Question 32

what kinds or solutes are freely permeable at all times

Answer 32

O2, CO2, and H20, lipids that are either non-polar and/or small

Question 33

what kinds of solutes need protein channels

Answer 33

simple sugars and amino acids

Question 34

when there is a difference in concentration between the inside and outside of a cell it is called a

Answer 34

gradient

Question 35

what are gradients

Answer 35

potential energy

Question 36

define the difference between chemical, electrical, and temperature

Answer 36

chemical- between molecule types electrical- between ionic charges temperature- between heat inside the cell and outside the cell

Question 37

what kind of energy moves solutes during diffusion and facilitated diffusion transport

Answer 37

potential energy

Question 38

what kind of energy moves solutes during active transport

Answer 38

cellular energy input or ATP

Question 39

how does osmosis differ from diffusion and active transport

Answer 39

water is moving to break up solutes, impermeable to solutes moves from lower to higher solute concentrations water follows solute

Question 40

what does osmolality measure

Answer 40

solute concentration of a solution

Question 41

how does osmolality different from hydrostatic pressure

Answer 41

hydrostatic pressure forces fluid out of the capillary osmotic pressure draws fluid back in

Question 42

what happens to cells when it is exposed to Isotonic solutions

Answer 42

solute concentration equal on both sides of membrane, concentration on inside and outside is the same

Question 43

what happens to cells when it is exposed to Hypertonic solutions

Answer 43

solute concentration less than inside cell, water is going to move into the cells and burst

Question 44

what happens to cells when it is exposed to Hypotonic solutions

Answer 44

solute concentration more than inside cell, outside is too much and leaves the cell, shrink