Question

1. compare law of independent assortment and law of segregation

2. (3 to 1 ratio) where does it come from? what is the parents genotype to get a 3 to 1 ratio?

3. what happens in deletion, duplication, inversion, and translocation?

4. if there's a mistake in the DNA and you want to fix it, what's the order of enzymes that need to be used in order to cut if off, repair it, seal it off?

Answer 1

Law of Seggrehation	Law of independent assortmment
Mendels First Law	Mendels Second Law
Describes the behaviour of allels	Describes the behaviour of nonhomologous Chromosomes
Monohybrid cross (Single trait)	Dihybrid cross or mutiple cross
production of haploid gamets through meiosis	inheritance of one character doesnot affect the inhritance of other character

2) 3:1 is the phenotypic ratio of the F2 population of monohybrid cross

To obtain 3:1 ratio the two parents must be homozygoys

TT=tall Tt= Short

F1= Tt= Tall F2= TT, Tt, Tt = tall (3) and tt= Short(1) = 3:1

3) Deletions: A portion of the chromosome is missing or deleted.

Duplication (Insertion): A portion of the chromosome is duplicated, which results in extra genetic material.

Translocations: When a portion of one chromosome is transferred to another non homologus chromosome is called as translocation.

Inversions: A portion of the chromosome has broken off, turned upside down and reattached, therefore the genetic material is inverted.

4) Incase of Base Excision repair the following enzymes are used

a) DNA glycolase (mismatch identification)

b) AP endonuclease and phosphodiesterase (cut)

c) DNA Polymerase (repair) and ligases (seal)