Cell membrane

Question 1

What is the main cell membrane bilayer made up of?

Answer 1

Phospholipid bilayer

Question 2

List the properties of the phospholipid

Answer 2

-Phosphate head: polar
-Fatty acid tail: non tail

Question 3

What is the cell membrane called (model) and why

Answer 3

Fluid mosaic model
There are many parts that make up the cell membrane (mosaic) such as proteins, lipids, sugars

The fluid parts comes from the membrane being fluid not static and keeps moving

Question 4

define intergal protein

Answer 4

-A protein embedded in the hydrophobic core
Usually spans the entire membrane

Question 5

define peripheral protein

Answer 5

Lies or sewered in the inner or other membrane
do not interact with the hydrophobic core

Question 6

How does cholesterol help the cell membrane?

Answer 6

Give membrane fluidity and stability
When heated the fluidity is reduced
When heated keep the membrane fluid

Question 7

Define oligosaccharide

Answer 7

Also known as sugar chain
Short chain of monomer
Cell recognition + attachment

Question 8

Define glycoprotein

Answer 8

Protein with sugar chain attached
Structural component
Receptors
Enzymes

Question 9

Define glycolipid

Answer 9

Phospholipid is sugar chain
Cell recognition markers
source of energy

Question 10

Define transport

Answer 10

Helps the substances that are too big to cross the cell membrane
Can be facilitated transport or active transport

Question 11

Define receptor for signalling

Answer 11

binds to hormones or growth factors
When bond they can trigger a signal that starts a cascade of reactions

Question 12

Enzymatic activities

Answer 12

Some proteins are involved in catalysing bio chemical reactions

Question 13

Attachment and recognition

Answer 13

Exposed to one side of the membrane
May attach t various components on extracellular matrix

Question 14

What is tonicity

Answer 14

Refers to the concentration of solute in the environment a cell is in

Question 15

explain endomembrane system

Question 16

What is isotonic

Answer 16

When the content of the cell and fluid around it has the same concentration of solute
Water moves in and out of the cell in equal amounts

Question 17

What is hypotonic

Answer 17

Fluid around the cell contains less dissolved solute than in the cell
Water will enter the cell and cause the cell to swell and end up causing plasmolysis

Question 18

What is hypertonic

Answer 18

Fluid around the cell contains more solute than inside the cell
Water leaves the cell to be with the more solute causing the cell to shrink

Question 19

Toncity in plant: hypotonic solution

Answer 19

The cell is happy
Water goes into the cell and fills up the central vacuole which pushes against cell wall. This helps maintain cell structure and keeps it turgid

Question 20

Toncity in plant: hypertonic solution

Answer 20

The cell wilts
Water leaves the cell and causes the central vacuole to loose all the water, so nothing is pushing against the cell wall and keeping it supported

Question 21

exocytosis

Answer 21

process cell for bulk transport
Process where cell moves large materials from inside the cell to extracellular fluid by transporting in vesicles (endomembrane system)

Question 22

function of exocytosis

Answer 22

Function: secretion (hormones enzymes), waste removal, repair and growth

Question 23

what is endocytosis

Answer 23

Process which a cell engluphs external materials by forming a pouch with it’s cell membrane then pinch it off to create a internal vesicle

Question 24

Phagocytosis

Answer 24

phagocyte takes in large/food/solid particles by their pseudopods and fuse the “fake feed” together to engulf the particle

Question 25

Pinocytosis

Answer 25

The bulk intake of extracellular fluid and small dissolved solute Cell membrane forms an inward pocket that traps the fluid to form small vesicles