Chapter 4: Genetic Inheritance

The pea plant was an excellent choice for Mendel’s experiments EXCEPT

• the plant can be self-fertilized

• it can be cross-fertilised

• true-breeding varieties were available

• long life cycle

What is the probability of producing offspring of homozygous genotypes from a dihybrid cross of heterozygous parents?

• 9/16

• 3/16

• 1/4

• 1/8

In pea plants, the trait for tall plants is dominant, T, and the trait for dwarf plants is recessive, t. The trait for yellow seed colour is dominant, Y, and the trait for green seed coat colour is recessive, y. A cross between two plants results in 298 tall yellow plants and 102 tall green plants. Which of the following are most likely to be the genotypes of the parents?

• TTYY x TTYY

• TtYy x TTYy

• TtYy x TtYy

• TTYY x ttyy

If a child is of blood type O, his or her parents could be as follows EXCEPT

• Type O mother and type O father

• Type AB mother and type O father

• Type A mother and type B father

• Type A mother and type O father

One experiment had a result on cross over value between gene P, Q and R. The cross over value between gene P and Q is 18%, gene Q and R is 12%, gene P and R is 6%. Which one of the statements below is TRUE about the gene?

• P is between Q and R

• crossing over does not occur between P and Q

• Q is between P and R

• R is between P and Q

When pink-flowered plants were crossed they produced offspring with red, pink, and white flowers in a ratio of 1:2:1. This is an example of………

• incomplete dominance

• codominance

• linked gene

• multiple allele

Breeding a yellow dog with a brown dog produced puppies with both yellow and brown hairs. This is an example of:

• codominance

• multiple allele

• linked gene

• incomplete dominance

________________________ refers to multiple independent pairs of genes having similar and additive effects on the same characteristic

• polygenic inheritance

• incomplete dominance

• codominance

• linked gene

A diploid individual has a maximum of ____________ different alleles for a particular locus.

• one

• four

• more than four

• two