Question 1

Which of the following best describes the central dogma of molecular biology?

Accepted Answer

Information flows from DNA to RNA to proteins.

Question 2

A gene is best defined as:

Accepted Answer

A section of DNA that codes for a specific protein or functional RNA.

Question 3

During meiosis in humans, how many chromosomes are present in each gamete?

Accepted Answer

$$23$$

Question 4

Which process is responsible for converting the information in DNA into mRNA?

Accepted Answer

Transcription

Question 5

A point mutation that changes a codon from $$UAC ($$tyrosine) to $$UAA ($$stop) is an example of which type of mutation?

Accepted Answer

Nonsense mutation

Question 6

If a diploid organism has five different alleles for a gene in the population, how many alleles for that gene could be found in a single individual?

Accepted Answer

Two

Question 7

Which of the following best explains why homologous chromosomes are not identical?

Accepted Answer

They carry the same genes but may have different alleles.

Question 8

A frameshift mutation is most likely to result from:

Accepted Answer

A deletion of two nucleotides.

Question 9

Which of the following is a real-world example of a beneficial mutation?

Accepted Answer

A mutation that increases resistance to malaria in heterozygotes.

Question 10

If a zorse is the offspring of a horse ($$2n = 64) $$and a zebra ($$2n = 44$$), how many chromosomes would you expect in a zorse's somatic cells?

Accepted Answer

$$54$$

Question 11

Which of the following statements about genotype and phenotype is correct?

Accepted Answer

Genotype determines phenotype through gene expression.

Question 12

A heterozygous individual for a gene with alleles $$A$$ and $$a$$ has which genotype?

Accepted Answer

$$Aa$$

Question 13

Which of the following best describes a silent mutation?

Accepted Answer

A mutation that does not change the amino acid sequence.

Question 14

During meiosis, when do homologous chromosomes separate?

Accepted Answer

During meiosis I

Question 15

Which of the following is an example of a chromosomal mutation?

Accepted Answer

A duplication of an entire chromosome.

Question 16

If a mutation changes the DNA sequence $$TAT ($$coding for tyrosine) to $$TGT ($$coding for cysteine), what type of mutation has occurred?

Accepted Answer

Missense mutation

Question 17

Which of the following best explains the principle of segregation as described by Mendel?

Accepted Answer

Each individual has two alleles for each gene, which separate during gamete formation.

Question 18

A mutation that decreases the ability of an organism to survive and reproduce is called:

Accepted Answer

Deleterious

Question 19

Which of the following best describes the structure of a eukaryotic chromosome?

Accepted Answer

A single long DNA double helix wrapped around histone proteins.

Question 20

If a point mutation occurs in the first nucleotide of a codon, what is the most likely consequence?

Accepted Answer

A change in the amino acid sequence, possibly altering protein function.

Information Flow, Genes, Mutations, and Meiosis: Foundations of Genetics

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