Cells And Cell Processes

Question 1

What is the cell theory?

Answer 1

• all organisms are composed of cells
• the cell is the basic ‘unit’ of life
• cells are formed from pre-existing cells during cell division
• energy flow occurs within cells
• hereditary information is passed on from cell to cell when cell division occurs
• all cells have the same basic chemical composition

Question 2

What does the cell membrane do?

Answer 2

Controls substances entering and leaving the cell

Question 3

What supports the cell?

Answer 3

Cell wall

Question 4

What does the chloroplast do?

Answer 4

Absorbs light for photosynthesis

Question 5

What does the nucleus do?

Answer 5

Controls the activities of the cell

Question 6

What does the vacuole do?

Answer 6

Filled with cell sap to keep the cell keep turgid.

Question 7

What does the cytoplasm do?

Answer 7

Where most chemical reactions take place

Question 8

Difference between animal and plant cells

Answer 8

Plant cells have a cell wall, chloroplast and large permanent vacuole.

Animal cells don’t.

Question 9

What is believed to be the oldest form of cell?

Answer 9

Bacteria

Question 10

What can micro-organisms cause?

Answer 10

Diseases (pathogens) or useful things (antibiotics)

Question 11

What does a bacterial cell contain?

Answer 11

Cytoplasm, cell membrane and cell wall

Question 12

Is there DNA and a nucleus in a bacterial cell?

Answer 12

There is no obvious nucleus and only a strand of circular DNA

Question 13

How does bacteria reproduce?

Answer 13

By dividing in two to form clones

Question 14

Who described the cell first? When?

Answer 14

Robert Hooke

1665

Question 15

Are yeast cells larger or smaller than bacteria cells?

Answer 15

Larger

Question 16

How do yeasts reproduce?

Answer 16

They reproduce asexually by a process names ‘budding’

Question 17

Are viruses larger is smaller than bacteria?

Answer 17

Smaller

Question 18

How do viruses reproduce?

Answer 18

Can only reproduce in a host cell

Producing new viruses destroys the host cell as the new viruses are released, meaning they are then free to attack other cells.

Question 19

What is contained in the fungi Kingdom?

Answer 19

Mushrooms
Toadstools
Mould
Yeast

Question 20

What do Yeast cells have? (Part of cells)

Answer 20

Nucleus
Cytoplasm
Cell membrane
Cell wall

Question 21

What parts of the cell do algae have?

Answer 21

Cell wall
Cell membrane 
Cytoplasm 
And an OBVIOUS nucleus 
Chloroplasts- therefore are photosynthetic

Question 22

Reasons why viruses can be classed as living organisms:

Answer 22

They have genes

Can reproduce and infect other cells

Question 23

Reasons why viruses CANNOT be classed as living organisms:

Answer 23

They can be crystallised
Can only reproduce using the resources of a host cell
They need to be inside a host cell to survive
They do not have their own metabolism

Question 24

How does the nucleus control the cell?

Answer 24

The nucleus contains chromosomes
Chromosomes are strands of DNA
Genes are sections of DNA molecules that determine the sequence of amino acids that make up the different types of proteins produces in cells.
Some of these are enzymes which control processes.
Enzymes affect the functioning of the cell and the organisms characteristics.

Question 25

The four bases of DNA:

Answer 25

Adenine Thymine Cytosine Guanine

Question 26

What is DNA made up of?

Answer 26

Two long chains of alternating sugar and phosphate molecules connected by bases. This structure is twisted to form a double helix.

Question 27

How does DNA work? (Bases)

Answer 27

Order of bases forms a code. Every three bases form a triplet code. This code determines the order in which different amino acids are linked to form different proteins during protein synthesis

Question 28

Who is credited for the discovery of DNA?

Answer 28

Francis Crick | James Watson

Question 29

Which cell division produces 2 genetically identical cells?

Answer 29

Mitosis

Question 30

What is mitosis needed for?

Answer 30

Making new cells for growth of body Making new cells to replace those that have been damaged Make new cells to replace those that have worn out.

Question 31

What is the original cell called in cell division?

Answer 31

Mother cell

Question 32

How does meiosis differ from mitosis?

Answer 32

The new cells of meiosis are different from the mother cell Meiosis only takes place in tissues which form sex cells

Question 33

What happens in meiosis?

Answer 33

Four gametes are produced Each gamete contains only one pair of chromosomes , so they only contain half the chromosome number of the original cell

Question 34

Comparison of production between meiosis and mitosis

Answer 34

Mitosis produces two daughter cells Meiosis produces 4 gametes

Question 35

Comparison of number of chromosomes of meiosis and mitosis

Answer 35

Mitosis contain original number of chromosomes Meiosis contains half the original number of chromosomes

Question 36

Comparison of meiosis and mitosis to mother cell

Answer 36

Mitosis- genetically identical to mother cell Meiosis- genetically different to mother cell

Question 37

What do tissues and organs form when they start to develop?

Answer 37

They form specialised cells