membranes

Question 1

what is the usual diameter for human cells

Answer 1

10-15 um in diameter

Question 2

what is the diameter of human egg cells

Answer 2

100 um

Question 3

axons can be up to ___m long

Answer 3

1

Question 4

what is the diameter of a human red blood cell

Answer 4

7-8 um

Question 5

what are two reasons cells are so small

Answer 5

SA to volume ratio would make it

-inefficient for nourishment/ waste removal

-time required for diffusion would be too long

Question 6

when one side doubles in length of a cell, the surface area increses _____-fold, and the volume increases ____-fold

Answer 6

4

8

Question 7

breakdown in % of
phospholipids
cholesterol
glycolipids
protein

in a cell membrane

Answer 7

phospholipids: 75%

cholesterol: 20%

glycolipids: 5%

protein: 2%

Question 8

function of phospholipids, cholesterol, glycolipids, and protein in a cell membrane

Answer 8

phospholipids: billayer properties

cholesterol: stiffness

glycolipids: cell non-self recognition

protein: 50% of weight (only 2% composition)

Question 9

what are transmembrane proteins

Answer 9

completely go through membrane into the cytoplasm

Question 10

what are the rafts made of that proteins on the membrane are clustered on

Answer 10

cholesterol

Question 11

what type of transmembrane protein is this:

binds to chemical messengers sent by other cells

Answer 11

receptor

Question 12

what type of transmembrane protein is this:

breaks down a chemical messenger and terminates its effect

Answer 12

enzyme

Question 13

what type of transmembrane protein is this:

constantly open and allowed solutes to pass in and out of the cell

Answer 13

channel

Question 14

what type of transmembrane protein is this:

opens and closes to allow solutes through but only at certain times

Answer 14

gated channel

Question 15

what type of transmembrane protein is this:

glycoprotein distinguishing the body’s own cells from foreign cells

Answer 15

cell identity marker

Question 16

what type of transmembrane protein is this:

molecule that binds one cell to another

Answer 16

cell adhesion molecule

Question 17

where does the second messenger come from

Answer 17

a receptor in the cytoplasm that received its messenger from a different messenger in the extracellular environment

Question 18

what is the glycocalyx

Answer 18

the fuzzy coat external to the plasma membrane

Question 19

glycocalyx is unique in everyone except

Answer 19

identical twins

Question 20

what is the function of the glycocalyx

Answer 20

an identification tag that enables the body to distinguish its own healthy cells from t

Question 21

what are microvilli and what is their function

Answer 21

projections on a cell membrane that increase surface area

Question 22

what is the boarder that is composed of microvilli called

Answer 22

the brush boarder

Question 23

what are cilia and what is their size relative to microvilli

Answer 23

projections on a cell membrane that are larger than microvilli

Question 24

what is the function of cilia (2)

Answer 24

to help the cell move

in the lungs, dust gets caught in them

Question 25

what are flagella

what do they do

what are the only cells theyre found in

Answer 25

projections on cell membrane

move a cell

sperm

Question 26

most cells have 1 _______ cilia, and its called the

Answer 26

nonmotile

primary cilium

Question 27

what are pseudopods

what are their function (3)

Answer 27

membrane extensions

engulf/ move/ interact with different cells

Question 28

what 2 types of transport require energy input

Answer 28

active transport

bulk transport

Question 29

what 3 types of cell transport do not require energy input

Answer 29

osmosis

diffusion

facilitated diffusion

Question 30

is filtration active or passive

how does it work

Answer 30

passive

particles driven though membrane with physical pressure

Question 31

what is facilitated diffusion

does it go with or against the gradient

does it require energy input

Answer 31

diffusion with the help of a protein on the cell membrane

with

no

Question 32

what do cells look like when theyre in a _____ solution

hypertonic

hypotonic

Answer 32

shriveled

inflated

Question 33

how do uniport carriers work

Answer 33

channel with one thing that moves though it

Question 34

how do symport channels work

Answer 34

2 different molecules move though it in the same direction

Question 35

how do anti port channels work

Answer 35

moves 2 different things at the same time in OPPOSITE directions

Question 36

how does secondary active transport work

Answer 36

when one thing can move up its concentration gradient because its coupled with something else moving down the gradient

(both going into the cell)

Question 37

what is vesicular transport

what does it move

does it require ATP

Answer 37

moves partivels by creating a vesicle around them and motor proteins are involved in this process

large/ multiple particles and fluid droplets

yes

Question 38

brief description of these types of endocytosis:

phagocytosis:

pinocytosis:

Answer 38

cell “eating”

cell “drinking”

Question 39

receptor mediated endocytosis in 3 steps

what is the protein involved with this process

Answer 39

1. molecules bind to receptors on membrane and receptors cluster together
2. membrane sinks inward and creates a pit
3. pit separates from membrane and becomes its own vesicle

clathrin

Question 40

what is transcytosis

Answer 40

transporting materials by capturing it on one side and releasing it on the other

Question 41

what are 2 functions of exocytosis

Answer 41

secreting material

replacement of plasma membrane removed ny endocytosis

Question 42

what are peripheral proteins in the cell membrane

Answer 42

do not protrude into the phospholipid layer, but adhere to either the inner or outer face of the membrane