test1: ch6

Question 1

cell membrane is _________ ________ which means it only allows certain molecules through

Answer 1

selectively permeable

Question 2

type of transport where no energy is required; substances move across membrane from high concentration to low concentration

Answer 2

passive transport

Question 3

small, nonpolar (hydrophobic) molecules can move easily through the cell membrane from high to low concentration because membrane is mostly made of lipids (nonpolar)

Answer 3

diffusion

Question 4

the rate of diffusion increases with:

Answer 4

increased concentration gradient, surface area, temperature, and permeability of membrane

Question 5

movement of water across a membrane from high water concentration to low water concentration (water moves from low solute concentration to high solute concentration)

Answer 5

osmosis

Question 6

some larger, polar (hydrophilic) substances need a protein carrier or protein channel in membrane that allow the substance to p ass directly through or change conformation when substance binds to release substance on other side (move from high to low with no energy expended)

Answer 6

facilitated diffusion

Question 7

what are integral proteins?

Answer 7

proteins that allow a substance to pass directly through (channel) or change conformation when substance binds to release substance on other side (carrier), during facilitated diffusion

Question 8

type of transport where energy is required; substances pumped across membrane from low concentration to high concentration (against concentration gradient)

Answer 8

active transport

Question 9

solvent + solute = ???

Answer 9

solution

Question 10

in osmosis, substance that is doin the dissolving (in this case water)

Answer 10

solvent

Question 11

in osmosis, substance that is being dissolved

Answer 11

solute

Question 12

passive movement of water across a membrane

Answer 12

osmosis

Question 13

t or f: during osmosis, water moves from where there is more water to where there is less water

Answer 13

true

Question 14

measure of force needed to stop osmosis

Answer 14

osmotic pressure

Question 15

the _______ the solute concentration, the _________ the osmotic pressure

Answer 15

higher; higher

Question 16

what happens to a red blood cell placed in an isotonic solution?

Answer 16

isotonic solution has same solute concentration as the red blood cell; water will move in and out of cell, the size of cell will stay the same

Question 17

what happen to a red blood cell placed in a hypotonic solution?

Answer 17

hypotonic has lower solute concentration than inside the cell; water will move from the solution into the cell, causing the cell to swell and potentially burst (hemolyse)

Question 18

what happens to a red blood cell placed in a hypertonic solution?

Answer 18

hypertonic has higher solute concentration than inside the cell; water will move from the cell into the solution causing it to shrivel or become smaller (crenate)

Question 19

in epithelial cell junctions, the type of junction that tightly locks cells together making it very difficult for diffusion to occur between cells

Answer 19

tight junction

Question 20

in epithelial cell junctions, the type of junction where cells are held close

Answer 20

adherens junction

Question 21

products produced within the cells, packaged in vesicle, vesicle fuses with cell membrane and contents are released outside the cell

Answer 21

exocytosis

Question 22

substances outside the cells interact with the cell membrane, the membrane folds in, engulfing the substance, and the substance is brought into the cell in a vesicle

Answer 22

endocytosis

Question 23

“cell drinking” - large amounts of water can be brought into the cell in this manner

Answer 23

pinocytosis

Question 24

“cell eating” - cells engulf microorganisms and cell debris

Answer 24

phagocytosis

Question 25

substance binds to receptors on the cell membrane and then brought into cell through endocytosis

Answer 25

receptor-mediated endocytosis

Question 26

most abundant cation in ICF is…

Answer 26

K+ (potassium ion)

Question 27

most abundant cation in ECF…

Answer 27

Na+ (sodium ion)

Question 28

if Na+ and K+ are allowed to freely move across the membrane:

K+ will move out of the cell along its electrochemical gradient until it reaches equilibrium at ___ mV

Answer 28

-90 mV

Question 29

if Na+ and K+ are allowed to freely move across the membrane:

Na+ will move into the cell along its electrochemical gradient until it reaches equilibrium at ___ mV

Answer 29

+66 mV

Question 30

resting membrane potential ranges from ___ mV to ___ mV depending on the cell type

Answer 30

-85 mV to -65 mV

Question 31

type of signal where ions and molecules pass between cells through channels (important in cardiac muscle)

Answer 31

gap junctions

Question 32

type of signal where cells release molecules that diffuse and communicate with nearby cells

Answer 32

paracrine signaling

Question 33

type of signaling where neurons release chemicals (neurotransmitters) across a junction (synapse) to communicate with another neuron, a muscle cell, or a gland

Answer 33

synaptic signaling

Question 34

type of signaling where endocrine glands produce hormones that travel through the blood to a target cell

Answer 34

endocrine signaling

Question 35

true or false: signal molecules must bind to specific protein receptors on or in their target cells

Answer 35

true

Question 36

common second messengers are:

Answer 36

cAMP and G-proteins (alpha, beta, and gamma subunits)