Mendelian Inheritance I

Question 0

Heterozygote:

Answer 0

An individual organism possessing two different alleles at a locus

Question 1

Locus:

Answer 1

Specific place on a chromosome occupied by an allele

Question 2

Homozygote:

Answer 2

An individual organism possessing two of the same alleles at a locus

Question 3

Monohybrid cross:

Answer 3

A cross between two parents that differ in a single characteristic

Question 4

What are Mendel’s conclusions from monohybrid crosses?

Answer 4

1. Each plant must possess two genetic factors (alleles) coding for a character
2. Two alleles in each plant separate when gametes are formed; one allele goes to each gamete
3. Mendel referred to the traits that appear unchanged in the heterozygous F1’s as dominant
4. Traits that disappeared in F1 heterozygotes were termed recessive

Question 5

What is mendel’s first law?

Answer 5

Principle of segregation: each individual diploid organism possesses two alleles for any particular characteristic. These two alleles segregate when gametes are formed, and one allele goes into each gamete

Question 6

What is the concept of dominance:

Answer 6

When two different alleles are present in a genotype, only the trait encoded by one of them - the “dominant” allele - is observed in the phenotype

Question 7

Law of segregation: Two alleles of an individual plant separate with _______ into the gametes

Answer 7

Equal probability

Question 8

Who is walter sutton?

Answer 8

Graduate student at columbia university in early 1900s
Studied meiosis in insects
Observed that each pair of homologous chromosomes consists of one maternal and one paternal chromosome
The homologous chromosome segregate independently into gametes
Concluded that this is the biological basis for Mendel’s principles
Homologous chromosomes separate during anaphase 1

Question 9

What are the possible ratios in a cross with 1 pair of alleles

Answer 9

3: 1 simple monohybrid cross
1: 2:1 monohybrid cross with incomplete dominance
1: 1 cross between homozygous parent and a heterozygous parent

Question 10

What combinations will create all the same offspring?

Answer 10

Hom Dom x hom dom
hom rec x hom rec
hom dom x hom rec
hom dom x hetero