Cell Membrane

Question 1

What do unsaturated phospholipids have?

Answer 1

more fluid as well as a double bond which creates a kink in the molecule.

Question 2

what is entropy?

Answer 2

measure of disorder of things

Question 3

what is osmosis?

Answer 3

simple diffusion of water through selectively permeable membrane

(passive process that occurs naturally)

Question 4

what is a hypotonic solution?

Answer 4

solution with a lot of water (ex: solvent)

water moves into RBC and it lyses (bursts)

Question 5

what is a hypertonic solution?

Answer 5

solution with less water (ex: solute)

water moves out of RBC and it becomes dehydrated

Question 6

in what direction does water move?

Answer 6

hypotonic –> hypertonic

down concentration gradient from more water to less water

Question 7

what makes a solution more hypertonic?

Answer 7

the more number of final particles it has

Question 8

what does isotonic mean?

Answer 8

same number of particles inside and outside cell

Question 9

what happens to RBC when places in hypotonic solution?

Answer 9

they lyse

Question 10

what does the sodium-potassium pump do?

Answer 10

exports 3 Na out of cell and imports 2 K in the cell

uses ATP

moves ions against concentration gradient (from low -> high)

Question 11

what is a hypotonic solution?

Answer 11

more particles inside cell than outside

Question 12

what is a hypertonic solution?

Answer 12

more particles outside cell than inside

Question 13

what is plasma membrane?

Answer 13

fragile, transparent barrier that contains cell contents and separates them from the surrounding environment

Question 14

interior of plasma membrane is impermeable to?

Answer 14

most water-soluble molecules.

cholesterol helps keep the membrane fluid

Question 15

what are proteins responsible for?

Answer 15

specialized functions in lipid bilayer throughout cell membrane.

receptors for hormones or other chemical messengers or are binding to sites for anchoring the cell to bikers or other structures

involved in transport

some proteins are enzymes

Question 16

what are protein channels?

Answer 16

water and small water-soluble molecules or ions can move through them

Question 17

what are carriers?

Answer 17

protein that binds to a substance and moves it through the membrane

Question 18

what is a glycoprotein?

Answer 18

sugar protein

makes the cell surface sticky due to the sugar

Question 19

what is glycocalyx

Answer 19

the fuzzy, sticky surface of the cell which is coated in sugar

Question 20

what do glycoproteins determine?

Answer 20

blood type

are receptors for certain bacteria/viruses/toxins

cell to cell recognition

Question 21

when do glycoprotein cells change?

Answer 21

when they transform into cancer cells

Question 22

what is a solution?

Answer 22

homogenous mixture of 2 or more components

Question 23

what is a solvent?

Answer 23

dissolving medium (water)

Question 24

what is a solute?

Answer 24

disolved in solvent

Question 25

what is intracellular fluid?

Answer 25

contains gasses, nutrients, salts and dissolves into water

Question 26

what is interstitial fluid?

Answer 26

continuously bathes the exterior of our cells

Question 27

what is selective permeability?

Answer 27

allows some substances to pass through while excluding others

Question 28

what is passive movement?

Answer 28

no ATP used

Question 29

what is active movemet?

Answer 29

ATP used

Question 30

diffusion?

Answer 30

molecules move from high concentration to low concentration (move down their concentration gradient) temperature and size of molecule affects speed of diffusion

Question 31

what can pass through the hydrophobic barrier?

Answer 31

small molecules lipid-soluble molecules molecules assisted by membrane carrier

Question 32

simple diffusion?

Answer 32

unassisted diffusion of solute through plasma membrane

Question 33

what is filtration?

Answer 33

water + solutes are forced through a membrane by fluid with use of pressure gradient from higher to lower pressure blood cells and large protein molecules are held back

Question 34

active transport?

Answer 34

uses ATP 1. active transport 2. endocytosis 3. exocytosis solute pump allows passage of amino acids, sugars, ions

Question 35

vesicular transport?

Answer 35

moves substances in/out of cell without crossing the plasma membrane by endocytosis or exocytosis

Question 36

exocytosis?

Answer 36

contents released from cell ATP used

Question 37

endocytosis?

Answer 37

contents brought into cell

Question 38

phagocytosis?

Answer 38

cell eating another cell

Question 39

pinocytosis?

Answer 39

cell drinking another cell

Question 40

passive transport: facilitated diffusion?

Answer 40

no ATP required 1. simple diffusion (non-polar molecules) 2. osmosis (hypotonic -> hypertonic) 3. facilitated diffusion (polar molecules)