B1.1

Question 1

Describe a Eukaryotic cell

Answer 1

They contain genetic material in the nucleus. They are complex and are relatively large with sizes between 10um and 100um.

Question 2

Give examples of Eukaryotic cells

Answer 2

Plant cells and animal cells

Question 3

Describe prokaryotic cells

Answer 3

They do not contain a nucleus but their genetic material floats in the cytoplasm. They are simple cells and are smaller than Eukaryotic cells with sizes of 1um to 10um

Question 4

Examples of prokaryotic cells

Answer 4

Bacteria cells

Question 5

What does a nucleus do?

Answer 5

A nucleus contains genetic material and it determines the cell’s appearance and function.

Question 6

What does a cell membrane do?

Answer 6

Has a selective barrier that controls what substances can pass in and out of the cell

Question 7

What does a cytoplasm do?

Answer 7

It’s a jelly like substance and it is where chemical reactions take place.

Question 8

What does a mitochondria do?

Answer 8

It’s where respiration occurs

Question 9

What does a chloroplast do?

Answer 9

They have green chlorophyll and that transfers energy from the sun and is used in photosynthesis

Question 10

What does a vacuole do?

Answer 10

It has cell sap and it helps the cell to keep rigid and keep it upright.

Question 11

What does a cell wall do?

Answer 11

It surrounds the cell and it has a tough fibre called cellulose and it supports the cell

Question 12

Describe bacteria

Answer 12

They are unicellular (one cell)

They are about 1um in size

Question 13

What are the seven different life processes?

Answer 13

Movement, Sensitivity, growth, reproduction, respiration, nutrition, excretion

Question 14

Examples of prokaryotes

Answer 14

E-coil- causes food poisoning
Streptococcus- causes sore throats
Streptomyces- found in the soil. It can kill many disease causing bacteria.

Question 15

What does the flagella do?

Answer 15

Has a tail- like structure to allow the cell to move through liquids

Question 16

What does the pili do?

Answer 16

Has tiny hair-like strictures that all the cell the cell to attach to structures like the cells that one in your digestive tract. They’re also used to transfer genetic materials between bacteria

Question 17

What is a slime capsule?

Answer 17

The layer outside the cell wall. It protects bacteria from drying out.

Question 18

What is a plasmid?

Answer 18

It is a circular piece of DNA used to store extra genes. May help in times of stress.

Question 19

What is a light microscope?

Answer 19

You use a light microscope to observe small structures in detail. You pass light through an object on a slide on the stage.

Question 20

Why do we stain cells?

Answer 20

Most cells are colourless so we use them to see the cell a lot more clearly.

Question 21

What are the three different kinds of stains used?

Answer 21

Methylene blue- used to see the nucleus of an animal cell
Iodine- makes it easier to see the plant cell nuclei
Crystal violet- so you can see bacteria cell walls

Question 22

What is an electron microscope?

Answer 22

It uses electrons to view an image and it creates a more clear resolution.

Question 23

What are TEM microscopes?

Answer 23

They are called transmission electron microscopes and they pass a beam a beam of electrons through a very thin slice of the sample and the beam is focused to produce an image