Biochemistry I Module of the MCAT Self Prep eCourse: Lesson 8: Genetics
(Pro)
Study online at https://quizlet.com/_40q6iy
1. Lesson 8: Genetics: Lesson 8: Genetics
2. *CRB* Gregor Mendel is often called the Father of Modern Genetics. Which
of the following are his Laws?
I. Law of Segregation
II. Law of Expressivity
III. Law of Independent Assortment
(A) I only
(B) I and III only
(C) II and III only
(D) I, II and III: (B) I and III only
Mendel's First Law is the Law of Segregation, and Mendel's Second Law is the Law of Independent Assortment.
3. *CRB* Which of the following is NOT one of the 4 tenets of the Law of
Segregation?
(A) Genes exist in alternate forms called alleles.
(B) Two alleles segregate in mitosis, resulting in gametes only carrying one
allele.
(C) An organism has two alleles per gene, with one from each parent.
(D) If the two alleles are different, one will assert dominance over the other,
making the other one silent.: (B) Two alleles segregate in mitosis, resulting in gametes only carrying
one allele.
This actually occurs in Meiosis, not Mitosis.
4. *CRB* True or false? The Law of Independent Assortment states the inheri-
tance of one gene is independent of the inheritance of another gene.: True. The
Law of Independent Assortment states the inheritance of one gene is independent of the inheritance of another gene.
5. Mutations are only a serious issue if they occur on the level of:
(A) DNA
, Biochemistry I Module of the MCAT Self Prep eCourse: Lesson 8: Genetics
(Pro)
Study online at https://quizlet.com/_40q6iy
(B) mRNA
(C) tRNA
(D) Protein: (A) DNA
A mutation in DNA will result in ALL future proteins being mutated.
6. DNA mutations may be inherited or they may occur spontaneously. Sponta-
neous mutations may result from:
I. DNA replication errors.
II. DNA transcription errors.
III. Environmental factors.
(A) I Only
(B) I and II Only
(C) I and III Only
(D) I, II, and III: (C) I and III Only
Spontaneous mutations may result from:
(1) DNA replication errors.
(2) Completely random events.
(3) Environmental factors.
7. Compare a Point Mutation to a Frame-shift Mutation.: A Point Mutation is when one
nucleotide in DNA is mutated into a different nucleotide. This may result in one amino acid being different in the mutant
protein, and may not change the amino acid at all. This type of mutation may not affect the function of the protein.
A Frame-shift Mutation is when one nucleotide is either added (Insertion) or taken away (Deletion), causing a shift in
the reading frame. This will result in all the amino acids downstream from that mutation to be changed. It often results
in a shorter version of that protein.
8. Why do frame-shift mutations often result in the mutant protein being short-
er than the wild type?: The shift in the reading frame may result in a new, earlier UAA, UGA, or UAG sequence
(called a "pre-mature stop codon").
(Pro)
Study online at https://quizlet.com/_40q6iy
1. Lesson 8: Genetics: Lesson 8: Genetics
2. *CRB* Gregor Mendel is often called the Father of Modern Genetics. Which
of the following are his Laws?
I. Law of Segregation
II. Law of Expressivity
III. Law of Independent Assortment
(A) I only
(B) I and III only
(C) II and III only
(D) I, II and III: (B) I and III only
Mendel's First Law is the Law of Segregation, and Mendel's Second Law is the Law of Independent Assortment.
3. *CRB* Which of the following is NOT one of the 4 tenets of the Law of
Segregation?
(A) Genes exist in alternate forms called alleles.
(B) Two alleles segregate in mitosis, resulting in gametes only carrying one
allele.
(C) An organism has two alleles per gene, with one from each parent.
(D) If the two alleles are different, one will assert dominance over the other,
making the other one silent.: (B) Two alleles segregate in mitosis, resulting in gametes only carrying
one allele.
This actually occurs in Meiosis, not Mitosis.
4. *CRB* True or false? The Law of Independent Assortment states the inheri-
tance of one gene is independent of the inheritance of another gene.: True. The
Law of Independent Assortment states the inheritance of one gene is independent of the inheritance of another gene.
5. Mutations are only a serious issue if they occur on the level of:
(A) DNA
, Biochemistry I Module of the MCAT Self Prep eCourse: Lesson 8: Genetics
(Pro)
Study online at https://quizlet.com/_40q6iy
(B) mRNA
(C) tRNA
(D) Protein: (A) DNA
A mutation in DNA will result in ALL future proteins being mutated.
6. DNA mutations may be inherited or they may occur spontaneously. Sponta-
neous mutations may result from:
I. DNA replication errors.
II. DNA transcription errors.
III. Environmental factors.
(A) I Only
(B) I and II Only
(C) I and III Only
(D) I, II, and III: (C) I and III Only
Spontaneous mutations may result from:
(1) DNA replication errors.
(2) Completely random events.
(3) Environmental factors.
7. Compare a Point Mutation to a Frame-shift Mutation.: A Point Mutation is when one
nucleotide in DNA is mutated into a different nucleotide. This may result in one amino acid being different in the mutant
protein, and may not change the amino acid at all. This type of mutation may not affect the function of the protein.
A Frame-shift Mutation is when one nucleotide is either added (Insertion) or taken away (Deletion), causing a shift in
the reading frame. This will result in all the amino acids downstream from that mutation to be changed. It often results
in a shorter version of that protein.
8. Why do frame-shift mutations often result in the mutant protein being short-
er than the wild type?: The shift in the reading frame may result in a new, earlier UAA, UGA, or UAG sequence
(called a "pre-mature stop codon").
