Cell Ultrastructure

Question 0

Give some functions of the plasma membrane

Answer 0

Selective permeability
Transport materials along cell surface
Endocytosis and exocytosis
Intercellular adhesion
Intercellular recognition
Signal transduction

Question 1

What is the limit of resolution?

Answer 1

The minimum distance at which two objects can be distinguished.

Question 2

By what type of phosphorylation do mitochondria produce ATP.

Answer 2

Oxidative phosphorylation

Question 3

What protein are micro tubules made out of?

Answer 3

Tubulin

Question 4

What is a process that occurs in the nucleolus?

Answer 4

Ribosomal RNA synthesis

Question 5

What does the smooth endoplasmic reticulum do?

Answer 5

Synthesises cholesterol and lipids. Also involved in the detoxification of certain drugs and toxins.

Question 6

What do ribosomes do?

Answer 6

Provide a surface upon which protein synthesis occurs.
Acts as a catalyst that facilitates the synthesis of proteins.
Site of translation

Question 7

What is the glycocalyx made out of and what is its function?

Answer 7

Glycoproteins and glycolipids

Gives the cell specificity

Question 8

What does the rough endoplasmic reticulum?

Answer 8

Synthesis and modification of proteins that are to be packaged. Also synthesis of membrane lipids and proteins.

Question 9

What is the function of the Golgi apparatus?

Answer 9

Sorts, concentrates, packages and modifies proteins synthesised in the RER.

Question 10

Where are lysosomes generated?

Answer 10

In the Golgi apparatus

Question 11

What do mitochondria do?

Answer 11

Generation of ATP by oxidative phosphorylation
Generating heat in brown fat
Assist in the synthesis of certain lipids and proteins

Question 12

What do lysosomes do?

Answer 12

Contain hydrolytic enzymes that function in intra cellular digestion.

Question 13

How big in diameter are most human cells?

Answer 13

10-20 micrometres

Question 14

What is the diameter of a red blood cell?

Answer 14

7.2 micrometres

Question 15

How many nanometers are in 1mm?

Answer 15

1,000,000

Question 16

What is a biopsy?

Answer 16

The removal of a small piece of tissue from an organ or part of the body for microscopic examination.

Question 17

Where can a curettage be used?

Answer 17

Endometrial lining of the uterus.

Question 18

For a biopsy, where can a needle be used?

Answer 18

Breast, brain, liver, kidney, muscle

Question 19

Give two tissue fixatives.

Answer 19

Glutaraldehyde

Formaldehyde

Question 20

Why do tissues need to be fixed?

Answer 20

Cross links are formed between macromolecules
Cellular structure is preserved
Prevents autolysis and putrefaction

Question 21

What colour does haematoxylin stain?

Answer 21

Blue/purple

Question 22

What type of components does eosin stain? Acidic or basic?

Answer 22

Basic eg cytoplasmic proteins and extracellular fibres

Question 23

What does PAS method stain and what colour is it?

Answer 23

Carbohydrates and glycoproteins

Magenta

Question 24

What colour does Elastic Van Gieson stain collagen?

Answer 24

Stains collagen pink/red

Question 25

What colour does Elastic Van Gieson stain elastin?

Answer 25

Blue/black

Question 26

What colour does Elastic Van Gieson stain muscle?

Answer 26

Yellow

Question 27

Why does an electron microscope have a finer resolution than a light microscope?

Answer 27

Limit of resolution is inversely proportional to wavelength and electrons have a much smaller wavelength than light.

Question 28

What do peroxisomes do?

Answer 28

Major site of oxygen utilisation and hydrogen peroxide production. Use HP to oxidise other substrates including phenols, alcohol, formic acid and formaldehyde.

Question 29

What does a cell's cytoskeleton do?

Answer 29

Maintains and changes cell shape Provides structural support for plasma membrane and cell organelles A means of movement for organelles, plasma membranes and other cytosol constituents.

Question 30

State the meaning of the term 'tissue'.

Answer 30

A collection of cells specialised to perform a particular function.

Question 31

List the functions of the nucleus

Answer 31

DNA storage | Co-ordinates the cell's activities; metabolism, growth, protein synthesis, mitosis

Question 32

Functions of the nuclear envelope?

Answer 32

Separates nuclear contents from the cell's cytoplasm | Nuclear pores allow specific types and sizes of molecules to pass through

Question 33

When does a ribosome bind to the ER?

Answer 33

When it is synthesising a protein bound for the secretory pathway.

Question 34

At which end of the Golgi body do vesicles fuse at?

Answer 34

The convex cis end.