Cycle 5 (Workshop + Study Session)

Question 1

Define:
Alleles

Answer 1

Variation in genome sequence

Question 2

Define:
Homologous allele

Answer 2

Same locus

Question 3

Assign gene and allele for the following trait:
Eye colour

Answer 3

Gene: Eye color
Allele: Blue

Question 4

During ________ ____, _______ can switch between __________ ___________

Answer 4

Crossing over
Alleles
Homologous chromosomes

Question 5

Is this true:
Alleles for the same trait are always on different spots on the same chrromosome

Answer 5

False, alleles for the same trait are always on same spot on the same chromosome

Question 7

True or False:
Homologous chromosomes can carry the same or different alleles

Answer 7

True

Question 8

What is it called when homologous chromosomes can carry the same or different alleles?

Answer 8

Homozygosity or heterozygosity

Question 9

Define:
Dominant allele

Answer 9

Only need one copy of allele to express phenotype

Question 10

Define:
Recessive allele

Answer 10

Need both copies of allele to express phenotype

Question 11

How is the dominant and recessive allele determined?

Answer 11

By observing the phenotype of the heterozygote

Question 12

What was the Blending Theory? How is it flawed?

Answer 12

Blending theory of inheritance was in the 1800s, stated that offspring have characteristics of both parents, therefore they must be a blend of both parents

Does not explain dominant and recessive traits

Question 13

State the Law of Segregation

Answer 13

Alleles segregate randomly into gametes

50% chance that either alleles end up in a gamete

Question 14

What does Mendel’s model comprise of?

Answer 14

Punnett’s square
Law of segregation

Question 15

What does Mendel’s model fail to explain?

Answer 15

Codominance and incomplete dominance

Question 16

Define:
Incomplete Dominance

Answer 16

Heterozygotes have intermediate expression

Question 17

Define:
Codominance

Answer 17

Both alleles are equally expressed in heterozygotes

Question 18

What is it called when the trait may be carried on either the X or Y chromosome?

Answer 18

Sex-linked

Question 19

Sex linked traits most commonly on the _ chromosome

Answer 19

X

Question 20

Define:
Epistasis

Answer 20

One gene interferes with expression of another gene expression

Question 21

Is epistasis a Mendelian inheritance?

Answer 21

No

Question 22

Define and give examples of:
Mendelian Inheritance

Answer 22

Dominant-Recessive Genes
Both alleles fully expressed, dominant allele masks the recessive allele
Monohybrid (Aa) Crosses Phenotypic Ratio, 3:1
Dihybrid (AaBb) Crosses Phenotypic Ratio, 9:3:3:1

Question 23

Define and give examples of:
Non-Mendelian Inheritance

Answer 23

Polygenic Traits
Epistasis
Codominance
Incomplete dominance
Sex-linked inheritance

Question 24

Define:
Polygenic traits

Answer 24

Many genes work together to form 1 phenotype

Question 25

What is the phenotypic ratio for epistasis?

Answer 25

9:3:4 (AaBb)