Red 2

Front 1

what part of the animal cell separates the living cell from it's nonliving surroundings?

Back 1

plasma membrane

Front 2

T/F the plasma membrane controls traffic in and out of a cell

Back 2

true

Front 3

how would you describe the plasma membrane's ability to keep things out?

Back 3

slightly permeable

Front 4

why is the plasma membrane suggested to be made of lipids?

Back 4

because lipids and lipid soluble materials can pass through

Front 5

the main macromolecules in membranes are what?

Back 5

lipids, proteins and some carboyhdrates

Front 6

what type of lipid is the most abundant in membranes?

Back 6

phospholipid

Front 7

when something has both hydrophobic regions and dyrodphilic regions its called what? give an example

Back 7

amphipathic , phospholipids

Front 8

what does the fluid mosaic model say?

Back 8

that the cell membrane is a fluid-like structure with proteins embedded or attached to a doulble layer of phospholipids

Front 9

membrane molecules are held in place by (strong/weak) hydrophobic/hydroliphic interactions?

Back 9

weak hydrophobic

Front 10

membrane fluidity is influenced by what?

Back 10

temperature

Front 11

As temperatures col, membranes in the cell swtich from a more ______ than a ______ as the phospholipids are more closely packed

Back 11

temperatures cool

Front 12

Phospholipids rich in unsaturated fats are more or less fluid than Phospholipids dominated by saturated fats and why?

Back 12

more fluid, because the kinks in the unsaturated fatty acid tails prevent tight packing.

Front 13

Where is steroid cholesterol located?

Back 13

between phospholipid molecules in the plastma membrane of eukaryotes

Front 14

At warm temp. choloesterol does what to phospholipid movement and fluidity?

Back 14

restrains movement and reduces fluidity

Front 15

At cool temp. cholesterol does what to phospholipid fluidity? and how

Back 15

maintinas fluidity by preventing close packing of the phospholipids

Front 16

What happens if membranes solidify?

Back 16

may inactiviate enzymes and cause changes in permeability. so membranes must maintian their fluidity or the cell dies

Front 17

There are two types of membrane proteins

Back 17

peripheral proteins and integral proteins

Front 18

Which of the two types of membrane proteins are not embedded inthe lipid bilayer at alll, but are loosely bounded to the surface of the membrane, often connected to other membranes

Back 18

preipheral proteins

Front 19

which of the two types of membrane proteins penetrate the hydrophobic core of th elipid bilayer?

Back 19

Intergral proteins

Front 20

The outer cell membrane plays a key role in what type of recognition?

Back 20

cell-cell recognition

Front 21

what is the ability of a cell to distringuish on type of neighboring cell from another?

Back 21

cell-cell regonition

Front 22

How do cells recognize other cells?

Back 22

by keying on the surface molecules (often carboyhydrates) on the plasma membrane

Front 23

which type of membrane are usually brancehd oligosaccharides with fewer than 15 sugar units?

Back 23

membrane carbohydrates

Front 24

When membrane carbohydrates are bonded to lipids they form

Back 24

glycolipids

Front 25

When membrane carbohydrates are bonded to proteins they form

Back 25

glycoproteins

Front 26

T/F small melecules and ions are positioned on the plasma membrane, unmoving.

Back 26

F, a steady traffic of small molecules and ions move across the plasma membrane in both directions

Front 27

Permeability depends on what?

Back 27

on the interaction of that molecule with the hydrophobic core of the membrane.

Front 28

How do hydrophobic molecules cross the memrbane?

Back 28

dissolving in the lipid bilayer and easily corssing hte membrane

Front 29

What cannot easily pass through a membrane unaided?

Back 29

Ions and polar molecules

Front 30

What assists and regulates the transport of ions and polar molecules across the membrane? why do they have to do so?

Back 30

Trasnport proteins that span the width of the membrane, they do this because ions and polar molecules cannot pass through the membrane unaided.

Front 31

Some trasnport proteins have a _________ that certain moleules or ions can use as a tunnel through th emembrane

Back 31

hydrophilic channel

Front 32

Besides the hydrophilic channel what else can a transport protein do to assist ions and polar molecules across the membrane?

Back 32

bind to their substrate moelucles and shuttle them across

Front 33

T/F transport proteins are unspecific as to the substances that it will transolcate?

Back 33

False, transport proteins are specific as to the substances they translocate

Front 34

What is the movement of molecules from areas of high concentration ot low concentration?

Back 34

diffusion

Front 35

Is energy required for diffusion?

Back 35

no

Front 36

What is diffusion driven by?

Back 36

Kinetic energy of molecules

Front 37

Molecules move up or down their concentration gradiets?

Back 37

down

Front 38

What is the regiona long which the density of a chemcial substance decreases

Back 38

concentration gradient

Front 39

what is the diffusion of a substance across a permeable biological membrane and y?

Back 39

passive transport because it requires no energy

Front 40

T/F Once molecules reach an equilibrium there is still movement of molecules

Back 40

true

Front 41

Once the cell reaches equilibrium what does this mean?

Back 41

that the number of molecules moving across the membrane equal the amount that are moving in the opposite direction

Front 42

What is it called when passive diffusion of moleucles is facilitated by a protein carrier that spans across the membrane?

Back 42

facilitated diffusion

Front 43

What have specific binding sites for the solute and can become saturated when they are translocating passengers as fast as they can and can be inhibited by molecules that resemble the normal subsrate?

Back 43

Transport proteins

Front 44

What are water channel proteins called?

Back 44

aquaprorins

Front 45

what do water channel proteins do?

Back 45

facilitate the massive diffusion fo water in some cells

Front 46

what is it called when channel proteins open or close dpeending on the preswense or absense of a physical or chemical stimulus?

Back 46

gated channels

Front 47

what is the diffusion of water across a semipermeable membrane?

Back 47

Osmosis

Front 48

Osmotic pressure increases or decreases as the number of praticles dissolved in solution increases?

Back 48

increases

Front 49

what refers to the relative concentrations of solutes inside and outside the cell's plamsa membrane?

Back 49

tonicity

Front 50

the solution with higher concentration of solutes is

Back 50

hypertonic

Front 51

the solution with the lower concentration of solutes is

Back 51

hypotonic

Front 52

Solutions with equal solute concentrations are

Back 52

isotonic

Front 53

Cells lose water when placed in hypo or hypertonic solutions?

Back 53

hypertonic

Front 54

cells gain water when placed in hypo or hypertonic solutions?

Back 54

hypotonic

Front 55

if two solutions on opposite sides of a membrane differ in _______, ______ continues until the solutions are ________

Back 55

tonicity, somosis and isotonic

Front 56

what functions as a bilge pump to force water out of the cell?

Back 56

contractile vauole

Front 57

How does a plant cell aid in maintining water balance?

Back 57

A plant cell in hypotonic solution will swell until the elastic wall opposses further uptake

Front 58

When plant cell loses water, its volume shrinks and eventaully the plastma membrane pulls away from the wall, this is called

Back 58

plasmaolysis

Front 59

what is th emovement of materials against their concentration gradients? opposite of the way they would move by diffusion

Back 59

Active transport

Front 60

what is teh movement of moleucles from low areas of concentration to high areas?

Back 60

active transport

Front 61

T/F active transport does not requre energy

Back 61

false it requres ATP energy

Front 62

a cytoplasm of a cel is negative or positive in charge?

Back 62

negative

Front 63

the membrane potential is what?

Back 63

-50 to-200 millivolts

Front 64

membrane potential favors the passive transport of cation and anions into the cell? cations or anions out of the cell?

Back 64

cations into the cell and anion out of the cell

Front 65

chemical force is based in an ion's

Back 65

concentration gradient

Front 66

electrical force is based on the

Back 66

the memrbane potential.

Front 67

what are special transport proteins that generate the voltage gradients across a memrbane?

Back 67

electrogenic pump

Front 68

what is a major elecotrogenic pump?

Back 68

proton pump

Front 69

what activiely transport Hydrogen ions out of the cell?

Back 69

proton pump

Front 70

what is the process by which a cel enculfs food particles and elminates undigested mateirals

Back 70

Endocytosis and exocytosis

Front 71

Endocytosis has three types

Back 71

pinocytosis, phagocytosis and carrier-mediated phagocytosis

Front 72

what type of endocytosis surrounds food with extensions of the cell membrane around the food, fuses with a lysosome containing digestive enxymes and food are broekn dwon.

Back 72

phagocytosis

Front 73

which type of endocytosis is the process by which fluids containing small molecules and ions are engulfed by the creation of tiny invaginations of t ememrbane forming tiny cesicles

Back 73

pinocytosis

Front 74

which type of endocytosis occurs when molecules bind to specific receptor proteins ont he surface of the membrane to form a vesicle

Back 74

receptor-mediated endocytosis

Front 75

what occurs when a vesicle containing undigested wastes or secreted products joins with the cell memrbane and the contents are released to the outside

Back 75

exocytosis