CELL BIOLOGY

Question 1

What is cell structure related to

Answer 1

cell function

Question 2

what are the levels of organisation

Answer 2

1. chemicals
2. cellular
3. tissue
4. organ
5. system
6. organism

Question 3

what are the different type of tissues

Answer 3

connective
nervous
skeletal
epithelial
cardiac
smooth

Question 4

why are cells small

Answer 4

for passive diffusion

Question 5

what’s a small uncharged molecule

Answer 5

ethanol

Question 6

what’s needed for effective diffusion

Answer 6

small volume and big surface area

Question 7

what is the plasma membrane

Answer 7

the outer layer of the cell
phospholipid bilayer
embedded proteins, lipids, carbohydrates
controls substances, signals into and out of the cells
helps maintain cytoplasmic composition, cell volume

Question 8

what is the functions of membrane proteins

Answer 8

a. receptor
b. enzyme
c. ion channel
d. gated ion channel
e. cell identity marker
f. cell adhesion molecule

Question 9

what is a receptor

Answer 9

a receptor that binds to chemical messengers such as hormones sent by other cells

Question 10

what is an enzyme

Answer 10

an enzyme that breaks down a chemical messenger and terminated its effect

Question 11

what is an ion channel

Answer 11

a channel protein that is constantly open and allows ions to pass in and out of cell

Question 12

what is a gated ion channel

Answer 12

a gated channel that opens and closes to allow ions through only at certain times

Question 13

what is a cell identity marker

Answer 13

a glycoprotein acting as a CIM distinguishing the body’s own cells from foreign cells

Question 14

what is a cell adhesion molecule

Answer 14

a CAM that binds one cell to another

Question 15

what is the cell nucleus

Answer 15

• surrounded by the nuclear envelop
• perforated by nuclear pores- channels that regulate molecular traffic
• chromatin: the genetic material of the cell (DNA) wrapped around proteins
• nucleolus- contains the genetic material for producing ribosomes

Question 16

what is the DNA structure

Answer 16

•nucleotides are the building block of DNA
•they have a:
nitrogenous base
pentose sugar
phosphate group
•changing the bases= chances the type of nucleotide

Question 17

what are the two type of nitrogenous bases

Answer 17

purines- 2 carbon stains

pyrimidines- 1 carbon stain

Question 18

what is the DNA structure

Answer 18

double helix
bases are orientated in inner part of and form weak hydrogen bonds
backbone is a repetition of phosphate deoxyribose (covalent strong)

Question 19

what is the endoplasmic reticulum

Answer 19

•a network of sacs directly contacted with the nucleus
•sacs are continuous and inter connected- one single lumen/ cisternal space
• allows molecules to be selectively transferred between nucleus ER cytoplasm
Rough ER- ribosomes- production of proteins
smooth ER - packing the proteins in vesicles for transport, synthesis of steroids and lipids, Ca2+ storage

Question 20

what is the Golgi complex

Answer 20

• system of cisternal that synthesise carbohydraes
• receives newly synthesises proteins from the rough ER and put the finishing touches on synthesis
• modifications: cutting, splicing, addition of carbohydrate
• finally pac