Genetics Station

Question 1

Purpose of Mitosis

Answer 1

• Passes along identical genetic
  information to daughter cells
• cell division

Question 2

Purpose of Meiosis

Answer 2

• Passes along genetic information to
  gamete cells in sexually
  reproducing organisms
• Make haploid cells

Question 3

How many stages of mitosis?

Answer 3

One stage. (divides only once)
4 phases + Interphase

Question 4

How many stages of meiosis?

Answer 4

Occurs in two stages.
1. Reduction = cells become haploid
2. Division = cells further multiply

Question 5

What are the types of cells involved in mitosis?

Answer 5

somatic cells (body cells) of multi-cellular organisms

Question 6

What are the types of cells involved in meiosis?

Answer 6

Both female and male gametes
Ex. sperm & ova in animals
Ex. pollen & ova in flowering plants

Question 7

Final outcome of mitosis?

Answer 7

• Produces diploid cells
• Identical to mother cell

Question 8

Final outcome of meiosis?

Answer 8

• Produces haploid cells
• Not identical to parent cells

Question 9

How many chromosomes in somatic cells after mitosis?

Answer 9

46

Question 10

How many chromosomes do human gametes have after meiosis?

Answer 10

23

Question 11

Mitosis: Prophase

Answer 11

• Chromosomes become visible and attach to spindle fibres
• Centrioles, appear and move to opposite sides of the cell
• The nucleolus disappears and the nuclear membrane starts to dissolve

Question 12

Mitosis: Metaphase

Answer 12

• Spindle fibres begin moving and aligning the chromosomes at the cell’s equator
• The chromosomes are pulled toward the centre
  of the cell
• Chromosomes centromeres become aligned at the center of the cell

Question 13

Mitosis: Anaphase

Answer 13

• Centromeres divide, sister chromatids move to opposite poles of the cell becoming
  individual chromosomes

Question 14

Mitosis: Telophase

Answer 14

• Chromosomes reach opposite poles of the cell
• The spindle fibres dissolve
• Nuclear membranes reform around each set of daughter chromosomes
• RESULT: TWO DAUGHTER NUCLEI!

Question 15

Interphase

Answer 15

• Increase protein supply
• Create more organelles
• Grow in size
• Duplicating DNA
• Not part of mitosis
• Consists of the G1, S and G2 phases of the cell cycle.

Question 16

Cytokinesis (follows mitosis)

Answer 16

• The cell membrane pinches inwards
• Final separation of the 2 daughter cells

Question 17

Meiosis: early prophase I

Answer 17

DNA is doubled

Question 18

Meiosis: Late prophase I

Answer 18

Chromosome pairs called “Homologous Chromosomes” overlap and carry out “crossover”

Question 19

Meiosis: Metaphase I

Answer 19

Chromosomes move to the equator of the cell and line up in pairs

Question 20

Meiosis: Anaphase I

Answer 20

• Homologous chromosomes move to opposite poles
• Chromosome number is halved
• Only one chromosome from each homologous pair will be in the new daughter cells

Question 21

Meiosis: Telophase I

Answer 21

• Nuclear membrane forms
• Genes are different on the chromosomes of the two nuclei

Question 22

Crossover

Answer 22

• Creates genetic variation between the gametes
• Occurs during prophase I where genes are shuffled between homologous chromosomes

Question 23

Meiosis: Prophase II

Answer 23

• Nuclear membrane dissolves
• Spindle fibers form

Question 24

Meiosis: Metaphase II

Answer 24

Chromosomes line up at the equator and are still attached at the centromere

Question 25

Meiosis: Anaphase II

Answer 25

• Sister chromatids separate to opposite poles
• Nuclear membranes form around chromatids

Question 26

Meiosis: Telophase II

Answer 26

Second nuclear division completed and 4 daughter cells formed