TT Biology Spring Midterm Review

What is a genotype?

• A cross where you have multiple options at 1 locus on a chromosome.  The ABO blood type is an example.

• Genetic makeup of an organism

• Physical appearance of a trait

• Crossing one trait at a time

What is a phenotype?

• Forms of a gene, represented by letters like A or a

• Crossing one trait at a time

• Physical appearance of a trait

• Crossing two traits at one time

What is an allele?

• A type of inheritance where traits blend

• Forms of a gene, represented by letters like A or a

• Genetic makeup of an organism

• A type of inheritance where 1 trait is influenced by two or more genes.

Homozygous means:

• Two different alleles (Aa) that make up the genotype

• Crossing one trait at a time

• Two identical alleles (AA) that make up the genotype

Heterozygous means:

• Two different alleles (Aa) that make up the genotype

• Crossing one trait at a time

• Two identical alleles (AA) that make up the genotype

In complete dominance, purple flowers (P) are dominant to white flowers (p). What color would the flower Pp be?

• Purple

• White

• Purple and white

Answer explanation

In complete dominance, if there is one capital letter, the genotype is dominant!

In incomplete dominance, a flower can be red (RR), white (WW), and RW, in which the flower would look like:

• Red

• Pink

• Red and White

Answer explanation

Incomplete means in-between (or a blend/mix or 2 colors)

In codominance, flowers can be red (RR), white (WW), and RW, in which the flower would look like:

• Red

• Pink

• Red and white

Answer explanation

'co' means together!

A mom is heterozygous for A blood. What would her genotype be?

• AA

• AB

• AO

• OO

What type of inheritance is present in a person with AB blood type?

• Polygenic

• Codominance

• Incomplete dominance

• Sex linked