Cell Division And Cellular Organisation

Question 1

Interphase stages

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Answer 1

G1 - organelles replicated
S - chromosomes replicated
G2 - Checked and repaired

Question 2

Prophase

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Answer 2

Chromosome condense and thicken, more visible

Nuclear envelope disintegrates

Centrioles go to opposite poles of cell and form spindle fibres

Question 3

Metaphase

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Answer 3

Chromosomes line up at cell equator

Spindle fibre attaches to centromere

Question 4

Anaphase

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Answer 4

Spindle fibre contracts

Centromere splits

Sister chromatids pulled to opposite poles of the cell
(active process)

Question 5

Telophase

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Answer 5

Spindle fibres disintegrate

Nuclear envelope forms around chromatids

Question 6

Cytokinesis

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Answer 6

Cytoplasm splits

Question 7

Define homologous pair

Answer 7

Chromosomes contain same genes but different alleles

Question 8

What new thing happens in meiosis prophase 1

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Answer 8

Crossing over of chromosomes occurs

Chaismata forms

Question 9

What can occur in metaphase 1 and 2?

Answer 9

Independant assortment

Question 10

What are plant stem cells?
Where are they found?
What do they differentiate into?

Answer 10

Meristems
Found at root and shoot tip
Differentiate into xylem and phloem tissue

Question 11

How thick are outside walls of guard cells?

How about inside wall thickness?

Answer 11

Outside wall is thin
Inner wall is thick
(causes outward bending)