Unit 3 Genetics Review

Inheritance Vocabulary

100

1. What is the term for the basic unit of heredity that determines traits and is passed from parents to offspring?
   A. Allele
   B. Gene
   C. Chromosome
   D. Nucleus

B. Gene

200

1. Where in the cell is DNA primarily found?
   A. Cytoplasm
   B. Cell membrane
   C. Mitochondria
   D. Nucleus

D. Nucleus

300

1. Which of the following best describes the relationship between DNA and genes?
   A. Genes are smaller than DNA
   B. DNA is found within genes
   C. Genes are segments of DNA that code for specific traits
   D. DNA and genes are completely separate structures

C. Genes are segments of DNA that code for specific traits

400

How many pairs of chromosomes can be found in a typical human cell?

A. 46 pairs

B. 23 pairs

C. 12 pairs

D. 22 pairs

B. 23 pairs

500

Which of the following describes the difference between an allele and a gene?

A. A gene is more specific than an allele

B. Genes and alleles are two different structures that determine inheritance

C. Alleles are the specific types of genes one can have.

D. Alleles are smaller segments of genes.

C. Alleles are the specific types of genes one can have.

Punnett Squares

100

1. What is a Punnett square used for?
   A. To determine the structure of DNA
   B. To predict possible genotypes of offspring
   C. To calculate mutation rates
   D. To determine the age of fossils

B. To predict possible genotypes of offspring

200

1. What term describes an organism that has two identical alleles for a particular trait?
   A. Heterozygous
   B. Recessive
   C. Phenotype
   D. Homozygous

D. Homozygous

300

1. What is the term for the physical expression or appearance of a trait?
   A. Genotype
   B. Phenotype
   C. Heredity
   D. Dominance

B. Phenotype

400

1. If a dominant allele is represented by "T" and a recessive allele by "t", which genotype would show the recessive phenotype?
   A. TT
   B. Tt
   C. tt
   D. Both B and C

C. tt

500

Brown eyes is dominant to blue eyes. If a brown eyed man whose father had blue eyes marries a brown eyed woman whose mother had blue eyes, what is the possibility that their offspring would have blue eyes?

25%

DNA Structure

100

What is the best way to describe the structure of DNA?

A. Single strand

B. Double helix

C. Triple coil

D. Spiral staircase

B. Double helix

200

1. What are the basic building blocks (monomers) of DNA?
   A. Amino acids
   B. Nucleotides
   C. Proteins
   D. Chromosomes

B. Nucleotides

300

1. Which of the following is NOT a component of a nucleotide?
   A. Sugar
   B. Phosphate
   C. Amino acid
   D. Nitrogenous base

C. Amino acid

400

1. What holds the two strands of DNA together?
   A. Covalent bonds between phosphate groups
   B. Hydrogen bonds between complementary bases
   C. Ionic bonds between sugars
   D. Peptide bonds between nucleotides

B. Hydrogen bonds between complementary bases

500

1. If a DNA strand has the sequence ATGCTA, what would be the complementary strand?

TACGAT

Mutations

100

1. Which type of mutation occurs when a nucleotide is removed from a DNA sequence?
   A. Insertion
   B. Deletion
   C. Substitution
   D. Replication

B. Deletion

200

Which type of mutation occurs when a nucleotide is replaced by another nucleotide in a DNA sequence?
A. Insertion
B. Deletion
C. Substitution
D. Replication

C. Substitution

300

What determines whether a mutation is harmful or beneficial?

The environment

400

What mutation has occurred on this DNA strand?

Original: AGC TGC AAA GTC ATG

Mutated: TCG ACG TAT TCA GTA C

An extra adenine was coded in the third codon (insertion)

500

What macromolecule is directly affected by a mutation in DNA?

Proteins