cell membrane and cell transport

Question 1

function of glycoprotein

Answer 1

acts as a receptor site
cell recognition/cell adhesion
form hydrogen bonds with water to help stabilize membrane structure

Question 2

glycoprotein

Answer 2

protein + carbohydrate

Question 3

function of cholesterol in cell surface membrane

Answer 3

helps regulate membrane fluidity
maintains mechanical stability
prevents ions/water soluble molecules from leaking through the membrane

Question 4

width of cell membrane

Answer 4

7nm

Question 5

function of protein molecule

Answer 5

responsible for transportation of polar molecules

Question 6

explain what is meant by the term fluid mosaic

Answer 6

is an idea that describes the structure of the cell membrane,whereas the phospolipid and protein molecules are moving about within their monolayer, and the protein molecules are scattered

Question 7

what features of phospholipid molecules cause them to form a layer in the cell membrane?

Answer 7

a phospholipid has a hydrophilic head and a hydrophobic tail,the phospholipid head is attracted to aqueous environment which causes hydrogen bonding to take place between them, and the tails will face downwards because they are repelled by aqueous environment

Question 8

why is the term “fluid mosaic” an appropriate term to describe membrane structure?

Answer 8

because the phospholipid and protein molecules move about and the protein molecules are scattered not a layer

Question 9

explain why calcium ions do not pass through the phospholipid layer

Answer 9

because calcium ions are hydrophilic/are charged /have charge/soluble, and the phospholipid layer is hydrophobic

Question 10

types of proteins

Answer 10

channel protein and carrier protein

Question 11

carrier protein

Answer 11

water filled pores,allows charges particles(ions) to go through,has “gated” part of the protein molecules which can move to open or close the pores

Question 12

why do carrier proteins have a “gated “ structure

Answer 12

helps control ion exchange

Question 13

carrier proteins have a

Answer 13

binding site whereas substrates in need of transport will bind themselves whereas the protein changes shape

Question 14

describe the process of phagocytosis

Answer 14

the bacteria attaches itself to the receptor whereas the bacteria’s antibody attaches itself to the receptor ,opsonization takes place whereas the bacteria is marked for engulfing and phagocytosis whereas the cell membrane engulfs the bacteria to form a vacuole/vesicle enclosing the bacteria

Question 15

describe the function of lysosomes in destroying ingested bacterial cells

Answer 15

the lysosomes fuse with the vacuole /vesicle since lysosomes contain hydrolyctic enzymes which break down or digest protein the bacteria will be broken d

Question 16

roles of carrier proteins

Answer 16

allows transportation of polar molecules

Question 17

function of lysosomes

Answer 17

digestion of pathogens and bacteria

Question 18

set of factors that produce the most fluid cell surface membrane?

Answer 18

temperature
proportion of long fatty acid chains
proportion of phospolipids with unsaturated fatty acid chains

Question 19

unsaturated

Answer 19

double bond

Question 20

saturated

Answer 20

no double bond

Question 21

which contribute to cell recognition?

Answer 21

glycolipids and glycoproteins

Question 22

what is phagocytosis?

Answer 22

is the bulk uptake of solid material

Question 23

what is endocytosis?

Answer 23

is the engulfing of substances by the cell surface membrane,forming a sac.

Question 24

what is exocytosis?

Answer 24

is the releasing or removing of substances by the cell

Question 25

what is bulk transport?

Answer 25

is the taking in or giving out of a large number of substances all at once

Question 26

types of passive transport

Answer 26

simple diffusion

facilitated diffusion

Question 27

diffusion(simple diffusion)

Answer 27

is the net movement of molecules from a region of high concentration to a region of low concentration, down the concentration gradient

Question 28

facilitated diffusion

Answer 28

is the diffusion of molecules facilitated by a transport protein in a cell membrane

Question 29

types of active transport

Answer 29

active transport
osmosis
phagocytosis
endocytosis
exocytosis
bulk transport

Question 30

what is active transport?

Answer 30

is the net movement of molecules from a region of low concentration to a region of high concentration against the concentration gradient using energy from ATP

Question 31

factors that affect diffusion

Answer 31

temperature
the surface area
the steepness of the concentration gradient