test 2

Question 1

What is multifactorial inheritance?

Answer 1

Inheriting a trait that is caused by more than one gene.

Question 2

What is the difference between breeding experiments and pedigrees?

Answer 2

breeding experiments involve only descendants and no new individuals. Pedigree are best used for humans and other animals that have new individuals added to their family trees.

Question 3

What is a monomorphic gene?

Answer 3

A gene with only one wild type allele

Question 4

What causes sickle-cell anemia?

Answer 4

A single nucleotide substitution makes the incorrect amino acid and causes the protein to fold abnormally

Question 5

Define syndrome

Answer 5

A group of expressed phenotypes that occur together and are caused by the same illness

Question 6

What causes Huntington’s disease?

Answer 6

Too many repeats of glutamine (codon CAG). More than 40 repeats causes problems and the protein cannot fold correctly. The more repeats, the earlier the disease progresses.

Question 7

What causes repeats in the HD gene’s coding region? Keyword: slips

Answer 7

C and G can pair with each other, so sometimes the DNA polymerase “slips” during replication and they pair with each other instead the template strand.

Question 8

What are the characteristics of dominant autosomal inheritance?

Answer 8

• shows up in every generation
• at last one parent has to be affected
• males and females are affected equally and both transmit the gene

Question 9

What are the characteristics of recessive autosomal inheritance?

Answer 9

• does not usually show up in every generation
• affected individuals usually have two unaffected parents
• two affected parents can only have affected offspring
• males and females are affected equally and both transit the gene

Question 10

A mutation in ___________ causes decreased inhibition of muscle growth and is due to incomplete dominance in heterozygotes.

Answer 10

Myostatin

Question 11

The Y chromosome only determines ___________

Answer 11

maleness

Question 12

What are the characteristics of sex-linked dominant inheritance?

Answer 12

• affected individuals have at least one affected parent
• affected females usually pass the trait on to 50% of both male and female offspring
• affected males pass the trait on to all daughters

Question 13

What are the characteristics of sex-linked recessive inheritance?

Answer 13

• males are much more affected than females because they are hemizygous
• parents of affected males are usually normal

Question 14

mitosis only happens in _________

Answer 14

eukaryotes

Question 15

What is chromatin?

Answer 15

the complex of protein and DNA in a cell’s nucleus

Question 16

sister chromatids are joined at the ___________

Answer 16

centromere

Question 17

Define metacentric and acrocentric chromosomes

Answer 17

metacentric chromosomes have their centromeres in the middle of the chromosomes. acrocentric chromosomes have their chromosomes toward one end of the chromosomes.

Question 18

during G2 of the cell cycle, the cell _________ ____________ necessary for mitosis

Answer 18

synthesizes proteins

Question 19

what is the kinetochore

Answer 19

the site at which chromosomes are attached to microtubules

Question 20

In which stage of prophase I of meiosis does the synaptonemal complex form?

Answer 20

zygotene

Question 21

another word for tetrad

Answer 21

bivalent

Question 22

crossing over occurs in ___________ of prophase I of meiosis

Answer 22

pachytene

Question 23

the name of the nodules that facilitate the exchange of DNA along the synaptonemal complex in prophase 1 of meiosis

Answer 23

recombination nodules