The Cell Cycle

Question 1

Describe what happens in metaphase

Answer 1

• Spindle formed/centromere attatches to the spindle

- Chromosomes/chromatids line up along the equator (of the cell)

Question 2

Describe what happens in anaphase

Answer 2

• Chromosomes separate/pulled apart/centromere splits/

- To (opposite) sides/poles/centrioles (of cell)

Question 3

Describe how leaves without water supply lose mass

Answer 3

• (Water) transpired/evaporates/diffuses out
• (Via ) watr potential gradient/leaf has higher water potential
• Stomata open
• Water potential/diffusion gradient reduces (during investigation)
• Water not being replaced/no water supply
• Stomata close/closing

Question 4

Describe how DNA is replicated

Answer 4

• Strands separate/hydrogen bonds break (DNA helicase involved)
• Both strands act as templates
• (Free) nucleotides attach
• Complementary/specific base paring/ AT and GC
• DNA polymerase joins nucleotides (on new strand)
• H-bonds reform
• Semi-conservative replication/new DNA molecules contain one old and one new strand

Question 5

Name the roles of centromeres in mitosis

Answer 5

• Holds chromatids together
• Attaches chromatids to spindle
• Allows chromatids to be separated/move to opposite poles

Question 6

Describe the role of DNA helicase in DNA replication

Answer 6

• Separates/unwinds/unzips strnads/breaks hydrogen bonds

- (so) nucleotides can attach/strands can act as templates

Question 7

Name and explain the part of the cell cycle where a mutaion is most likely to occur

Answer 7

• Interphase

- DNA/gene replication/synthesis occurs/longest stage