Week 8

Question 1

Mendel’s Hypothesis

Answer 1

1. In the organism there is a pair of factors that controls the appearance of a given
   characteristic. (We call them genes.)
2. The organism inherits these factors from its parents, one from each.
3. Each factor is transmitted from generation to generation as a discrete, unchanging unit. (The
   wrinkled seeds in the F2 generation were no less wrinkled than those in the P generation
   although they had passed through the round-seeded F1 generation.)
4. When the gametes are formed, the factors separate and are distributed as units to each
   gamete. This statement is often called Mendel’s rule of segregation.
5. If an organism has two unlike factors (we call them alleles) for a characteristic, one may be
   expressed to the total exclusion of the other (dominant vs recessive).

Question 2

Law of Domiance

Answer 2

The law of dominance states that when two alternative forms of a trait or
character (genes) are present in an organism, only one factor expresses itself
in F1-progeny and is called dominant, while the other that remains masked is
called recessive.

Question 3

Law of Segregation

Answer 3

This law states that the alleles do not show any blending and
both the characters are recovered as such in the F2-
generation, though one of these is not seen in the F1 -
generation.

Question 4

Mendelian Inheritance

Answer 4

• This refers to traits where there are both a dominant and recessive allele present as
  heterozygous pair. The dominant allele has complete control over the phenotype.
• Not all traits are Mendelian traits some may be categorise as:
  o Incomplete dominance
  o Co dominance
  o Sex linkage
  o Autosomal linkage
  o Epistasis