Mutations and Pedigrees

Question 1

Somatic Mutations

Answer 1

occur in body cells
passed on by mitosis — cancer

Question 2

Germ line mutations

Answer 2

occur in germ line cells that give rise to gametes
passed on by meiosis —- mutated offspring

Question 3

Mutations can be caused by:

Answer 3

-mistakes during DNA replication, mitosis, meiosis, or protein synthesis
-Mutagens (chemicals that cause DNA mutations)
-Viruses

Question 4

Gene Mutation

Answer 4

happen during DNA replication and cause change to DNA sequence
ex. cystic fibrosis, dwarfism

Question 5

Point Mutation

Answer 5

substitute one nucleotide for another
-caused by replication errors/ environmental mutagens
-ex. sickle cell anemia

Question 6

Frameshift Mutation

Answer 6

insertion/ deletion of a nucleotide that affects all codons after the affected

Question 7

Chromosome Mutation

Answer 7

happen during meiosis, changing the number/ location of genes

Question 8

Duplication

Answer 8

changes the size of chromosomes and results in multiple copies of one gene

Question 9

Translocation

Answer 9

pieces of non-homologous chromosomes exchange segments (during Prophase I)

Question 10

Nondisjunction

Answer 10

chromosomes do not separate correctly in Anaphase, resulting in 1 or 3 chromosomes per cell

Question 11

Autosomal Recessive

Answer 11

-most common inheritance pattern
-disease is rare in family
-males and females are equally likely to get it
-often skips generations
ex. cystic fibrosis, sickle cell anemia, PKU

Question 12

Autosomal Dominant

Answer 12

-disease is common in the family
-males and females are equally likely to get it
-never skips a generation
-ex. achondroplasia, Huntington’s

Question 13

Sex-Linked Recessive (X-linked)

Answer 13

-disease is rare in the family
-males are affected more than females
-often skips generation
-fathers don’t pass on to sons bc dad had to give his Y to son
-ex. Hemophilia, DMD, colorblindness