Meiosis

Question 1

Mitosis

Answer 1

divison of somatic cells for either growth, repait, regeneration, or asexual reproduction (all cells excluding gametes)

Question 2

Meiosis

Answer 2

Cell division that occurs in gonads (ovary and testes and ovules etc) to produce haploid gametes

Question 3

Haploid gametes

Answer 3

half the full set of chromosomes

Question 4

diploid gametes

Answer 4

full set of chromosomes

Question 5

significance of meiosis

Answer 5

• produces gametes that are genetically variable
  (variation drives natural selection)
• gametes are haploid so that when fertilisation occurs, the resulting zygote is a diploid cell (prevents the doubling effect)
• Ensures that variation in offspring drives natural selection

Question 6

homologous pair of chromosomes

Answer 6

Similiar in shape and size
have genes at the same location

Question 7

crossing over

Answer 7

exchanging genetic info between inner chromatids
recombinant chromatids

Question 8

karyokinesis

Answer 8

division of nuclear material

Question 9

cytokinesis

Answer 9

division of cytoplasm

Question 10

process

Answer 10

interphase - DNA replicates

prophase I (2n) - crossing over (bivalent, chiasma),

Metaphase I (2n) - meeting at equator

Anaphase I - disjunction, spindle fibres (independant segregation

Question 11

Reason for variation

Answer 11

crossing over

independent assortment of chromosomes along equator

Question 12

karyotype

Answer 12

• individuals karyotype makeup
• 22 pairs autosomes
• 1 pair gonosomes (male or female)
• identifies chromosomal mutations
  (trisomy)

trisomy of larger chroms don’t make it to burth

Question 13

Chromosomal mutations

Answer 13

non disjunction:
- Anaphase I
- chromosome stays attached
- Anaphase II
- chromatid stays attached

translocation
- incorrect crossing over in metaphase I
- dislodged piece of chrom and attaching on another

Question 14

Aneuploidy

Answer 14

having 1 less or 1 more chromosome