U7T1 – Definitions, Monohybrid, Dihybrid and Codominance

What is a gene?

What is the definition of 'genotype'?

What is the definition of 'phenotype'?

What is the definition of 'allele'?

What is the definition of 'homozygous'?

What is the definition of 'heterozygous'?

What is the best definition of a 'dominant allele'?

What is the best definition of a 'recessive allele'?

How can you tell when an allele is recessive in a pedigree (a family tree)?

In guinea pigs, Short hair (S) is dominant to long hair (s). In a monohybrid cross between a heterozygous mother, with a heterozygous father, what ratio of long hair to short hair will the offspring have ?

In Guinea pigs, ginger(G) hair is dominant to white(g), and short hair (S) is dominant to long (s). In the following cross: GgSs and GgSS, what percentage chance will the offspring being born short haired and white?

In Guinea pigs, ginger(G) hair is dominant to white(g), and short hair (S) is dominant to long (s). In the following cross: GgSs and GgSS, what percentage chance will the offspring being born long haired and ginger?

Marfan syndrome is a dominant inherited disorder, where the suffer develops an increase in a growth factor ( TGF - beta) which effects connective tissue. What is the probability of a healthy mother and a heterozygous father having a healthy child?

How could you tell if Marfan Syndrome is Dominant by looking at a pedigree ( family tree)?

Marfan Syndrome ( TGF Beta) is dominant (T) to the healthy recessive allele(t) . Having a V shaped hairline (V) is dominant to having a straight hairline (v). What percentage of the offspring of a father = TtVv and a mother TtVv will have Marfan syndrome and a V shaped hair-line ?

Marfan Syndrome ( TGF Beta) is dominant (T) to the healthy recessive allele(t) . Having a V shaped hairline (V) is dominant to having a straight hairline (v). What is the percentage probability of the offspring of a father = TtVv and a mother = TtVv would have Marfan Syndrome and a straight hair - line ?

Marfan Syndrome ( TGF Beta) is dominant (T) to the healthy recessive allele(t) . Having a V shaped hairline (V) is dominant to having a straight hairline (v). What proportion of the offspring of a heterozygous father (TtVv) and a heterozygous mother (TtVv) will be health and have a V shaped hair-line ?

What does the term 'Codominance' mean?

A codominant allele' is when both alleles are expressed. One breed of chickens can have Black feathers(B) or White feathers(W). What phenotype will a chicken have with the genotype BW ?

If B = black, W = white and BW = speckled feathers in hens. Two heterozygous speckled hens mated, what will the ratios be of offspring that are black : speckled : white?