Tissues 1: Epithelial cells 1

Question 1

Which organelle has double membrane

Answer 1

The nucleus, it has an outer and inner membrane called the nuclear envelope

Question 2

What happens at the nucleolus

Answer 2

Ribosome subunits are produced

Question 3

What is the nuclear envelope continous with?

Answer 3

The ER

Question 4

Where are ribosome subunits produced

Answer 4

Nucleolus

Question 5

What is the function of ER

Answer 5

Packaging and processing proteins

Question 6

What are nuclear pores?

Answer 6

The are proteinc complexes that control what enters and leaves the nucleus

Question 7

What kinds of ER are there, what are there functions?

Answer 7

rER-Rough endoplasmic reticulum: Flattened sheets, continous with nuclear envelope and have ribosomes attached on its outer surface, involved in protein synthesis
sER-Smooth endoplasmic reticulum: Tubular membranes involved in lipid metabolism

Question 8

What is the golgi apparatus and what does it do?

Answer 8

Stacked, flattened membranes sacs which modify, package & sort macromolecules for secretion or delivery

Question 9

what are the compartments?

Answer 9

Cis face
Cis golgi network
Cis cisterna 
media cisterna 
Trans cisterna 
Trans golgi network 
Trans face
Golgi vesicle 
Secretory vesicle

Question 10

Explain:
Phagocytosis
Pinocytosis

Answer 10

Cell eating-Internaliation of large particles
Cell drinking-Internalisation of extracellular fluid
Major function=receptor mediated endocytosis

Question 11

Mitochondria?

Answer 11

Where ATP is produced via oxidative phosphorylation & TCA cycle

Question 12

Peroxisomes

Answer 12

Enzymes contained involved in lipid and oxygen metabolism

Question 13

What are the 3 types of filament?

Answer 13

Microtubules
Microfilaments
Intermediate filaments

Question 14

Microtubules

S&F

Answer 14

Polymers of alpha & beta tubulin 
20nm diameter (roughly)
some part in cell shape & act as tracks for organelles around cell 
Major components of cilia and flagella 
arranged in 9.2 formation in cilia 
Part of spindle fibres

Question 15

What is the name of the point from which Microtubules tend to radiate from

Answer 15

Microtubule organising centre(MTOC)

Question 16

Intermediate filaments

S&F

Answer 16

A group of filamentous proteins forming rope like filaments
10-15nm diameter(in between the other two)
Different cell types=different filalements
Give mechanical strength
Desmosomes: Connected by cytokeratins(IF)
Nuclear Lamins:Stabilise the envelope and are network of IF on internal surface

Question 17

Microfilaments

S&F

Answer 17

Actin polymer with adhesion belts to other plasma membrane proteins
Helical structure
Monomer=G actin, Polymer=F actin
Cell shape and movement
Done by accessory proteins associating with e.g. myosin
Usually near periphary of the cell
Can be broken down and reformed providing cell with mobility