Unit 5 Concept 3

Question 1

Mutation

Answer 1

• Any change in DNA
  (the order of nucleotide bases/letters)

Question 2

Mutagen

Answer 2

Chemical that can cause a mutation in DNA

Question 3

Duplication

Answer 3

A chromosome mutation that changes the size of chromosomes and results in multiple copies of a gene

Question 4

Translocation

Answer 4

A chromosome mutation that results when pieces of non-homologous chromosomes exchange segments during crossing over

Question 5

Nondisjunction

Answer 5

A chromosome mutation that results from chromosomes not
separating correctly during anaphase, causing the wrong
number of chromosomes in the resulting gametes

Question 6

Pedigree

Answer 6

Chart used to trace a trait/disease through a family tree

Question 7

Explain the difference between a mutation in a somatic cell / somatic mutations vs. a mutation in a gamete/germ line mutation

Answer 7

• A mutation in a somatic cell is passed on via mitosis and can result in cancer.
• A mutation in a gamete was passed on via meiosis and could result in an offspring with the mutation, if the gamete is fertilized.

Question 8

Explain the difference between gene and chromosomal
mutations. Include an example for how each can be caused.

Answer 8

• Gene mutation: A change to the original DNA sequence
  affecting a single gene.
• Can be caused by a mistake in DNA replication.
• Chromosome mutation: A change to a section of a
  chromosome that affects the number and/or location of multiple
  genes.
• Can be caused by a mistake in meiosis.

Question 9

Differentiate between point mutations and frameshift
mutations.

Answer 9

• Point mutation: One nucleotide is substituted for another.
• Frameshift mutation: One nucleotide gets added to or deleted from
  the sequence, causing all subsequent codons to be affected due to the
  change in the reading frame.

Question 10

Autosomal Recessive Inheritance pattern give example

Answer 10

• Autosomal recessive: males and females must inherit 2 recessive alleles with the disease in order to show it.
• Males and females are equally likely to inherit this disorder
  often skips generations
  Ex. Cystic Fibrosis

Question 11

Autosomal dominant Inheritance pattern give example

Answer 11

males and females only need to inherit 1 dominant allele with the disease in order to show it.
Never skips Generations
Males and females are equally likely to inherit this disorder
Ex. Huntington’s disease

Question 12

Sex-linked

Answer 12

males only need to inherit 1 affected X, whereas females must inherit the gene on both of their X chromosomes to show it.
Often skips generations
Males are often more affected than females
Ex. Duchenne Muscular Dystrophy

Question 13

If two parents that are not shaded (white) have a shaded baby that is the inheritance pattern

Answer 13

autosomal reccesive

Question 14

If two parents that are shaded have a not shaded baby (white) that is the inheritance pattern

Answer 14

Autosomal dominant

Question 15

Autosomal chromosomal

Answer 15

mutation on an autosome. Ex.
Nondisjunction of the 21st chromosome causes Down Syndrome

Question 16

Sex chromosomal:

Answer 16

mutation on sex chromosome. Ex. Nondisjunction
of the sex chromosomes can cause Turner Syndrome