Chapter 3e - Allelic Interactions

Question 1

laboratory method used to separate mixtures of DNA, RNA, or proteins according to molecular size.

Answer 1

Gel electrophoresis

Question 2

observed only in heterozygotes with dissimalr genes

Answer 2

allelic interactions

Question 3

Three different forms of dominance

Answer 3

1. complete dominance
2. incomplete dominance
3. codominant

Question 4

Allelic Interaction

Answer 4

1. Complete Dominance
2. Incomplete Dominance
3. Codominance
4. Allelic Complementation
5. Overdominance
6. Complex Dominance

Question 5

heterozygotes exhibit dominant trait with 1:2:1 genotypic ratio and 3:1 phenotypic ratio

Answer 5

complete dominance

Question 6

expressed only when the organism is homozygous recessive

Answer 6

recessive phenotype

Question 7

dictates a protein which actively participates in the development of the trait

Answer 7

dominant allele

Question 8

dictates a protein with no apparent activity or no protein at all

Answer 8

recessive allele

Question 9

occurs in situations where a single copy of a functional gene is enough to maintain normal function

Answer 9

Haplosufficiency

Question 10

Ex. of complete dominance

Answer 10

1. brachydactyly
2. polydactyly

Question 11

short fingers

Answer 11

brachydactyly

Question 12

dictate a protein whose presence interferes with development of normal fingers

Answer 12

polydactyly

Question 13

• F1s are intermediate between two parents
• recessive gene interferes in the expression of dominant trait
• recessive allele is not expressed in heterozygote

Answer 13

incomplete dominance

Question 14

ex. of incomplete dominance

Answer 14

1. red, pink, white rose
2. curly, wave, straight hair

Question 15

• phenomenon in which two alleles (different versions of the same gene) are expressed to an equal degree within an organism.
• As a result, traits associated with each allele are displayed simultaneously.

Answer 15

codominance

Question 16

Ex. of codominance

Answer 16

1. Human ABO blood groups
2. lentil coat patterns (spotted and dotted)
3. roan cattle

Question 17

similar to codominance but the different interaction between two alleles results in the production of a hybrid protein

Answer 17

allelic complementation

Question 18

allelic complementation is __ or __ __ among mutant alleles of a gene, representing different __

Answer 18

• partial or incomplete dominance
• cistrons

Question 19

• also known as heterosis or hybrid vigor
• hybrid superior to both parents
• 1:2:1 genotypic ratio
• very useful in plant/animal breeding

Answer 19

overdominance

Question 20

dominance relationships can be very __

Answer 20

complex