Question

The four nucleotides found in human DNA (G, A, T, C) combine in groups of three to create potentially 64 different amino acids, but only 20 amino acids, one start codon and three stop codons are used to construct proteins. Why is this so?
a.Many amino acids are not considered complete until they bind with a second amino acid.
b.64 amino acids are produced, but the body only integrates
c.42 of them into proteins. 64 amino acids are initially produced, but 42 of them are unstable and degrade immediately. Different d.nucleotide combinations code for the same amino acid.

2.What term is used to describe the phenomenon that there are 64 different groups of 3 nucleotides to code for amino acids but only 20 amino acids, 1 start codon, and 3 stop codon used in protein construction.

a.Crossing over
b.Redundancy
c.DNA structure
d.Transcription

Suppose a male and a female with chromosomes "DD" (male) and "dd" (female) crossbreed. How likely is their offspring to exhibit the DD genotype?

100%
25%
50%
0%

4.What term best describes the genotype of "dd"?
a.heterozygous
b.monohybrid
c.homozygous
d.haploid

5.Suppose a male and a female with chromosomes "DDBb" (male) and "ddBB" (female) interbreed. How likely is their offpsring to exhibit the DdBb genotype? 100% 50% 25% 0%?

6. What term best describes the breeding perfomed when a male and female with chromosomes "DDBb" (male) and "ddBB" (female) interbreed?

Dihybrid cross

Codominance

Incomplete dominance

Monohybrid cross

Answer 1

Question 1

Answer:

D- Different nucleotide combinations code for the same amino acid.

Explanation:

Some amino acid has more than one nucleotide combination coding for it.

Question 2

Answer:

B- Redundancy

Explanation:

Redundancy means that more than one codon is assigned for the coding of most amino acids.

Question 3

Answer:

0%

Explanation:

Since both parents are homozygous dominant and recessive respectively, no crossing can give the homozygous dominant as all offspring are heterozygous.                  

Question 4

Answer:

Homozygous.

Explanation:

The genotype 'dd' is homozygous since the two letters are both in the lower case.

Question 5

Answer:

25%                

Question 6

Answer:

Dihybrid cross