Bio practice quiz

Which of the following crosses will NOT produce offspring with the recessive phenotype?

a. TT x Tt

b. Tt x Tt

c. TT x TT

d. Tt x tt

e. tt x t

A. TT x Tt & C. TT x TT

What aspect of Mendel's background gave him the necessary tools to discover the laws of inheritance?

He had studied mathematics and probability.

What is the blending theory of inheritance?

offspring will show traits that are intermediate to the parents

In a classic Mendelian monohybrid cross between a parent who is homozygous dominant and a parent who is homozygous recessive, which generation is always completely heterozygous?

The F1 generation is always heterozygous in a Mendelian monohybrid cross.

The F2 offspring of a classic Mendelian monohybrid cross between homozygous dominant and homozygous recessive parents would produce the genotype(s)

The F2 offspring of a monohybrid cross would show the genotypes, AA, Aa, and aa.

The offspring of a monohybrid testcross could have what possible genotype(s)?

monohybrid testcross: aa x AA OR Aa= Aa and aa

What are alleles?

Different forms of a gene. (i.e Blue eyes)

If an individual with a dominant phenotype is crossed with an individual with a recessive phenotype, 4 of their 9 offspring show the recessive phenotype. What is the genotype of the first parent?

Aa

What statementis NOT true according to Mendel's law of segregation?

One factor must be dominant and one factor recessive in each individual.

What is a genotype?

genetic makeup of an organism

What is a phenotype?

physical characteristics of an organism

In what kind of classic Mendelian cross would you expect to find a ratio of 9:3:3:1 among the F2 offspring?

dihybrid cross

If the probability of event A is 3/4 and the probability of event B is 1/4, then the probability of both A and B occurring at the same time is

3/16 (3/4 x 1/4)

Describe normal Mendelian inheritance

Under normal Mendelian inheritance, two Rh- parents could NOT have an Rh+ child.

animal breeders who discover a unique trait and breed to increase the occurrence of that trait often encounter a noticeable increase in lethal genes. Why?

increases the chances that two recessive genes will "meet" in offspring