Lecture 4

Question 1

Is sex determination the same in all organism? (know the answer and anything else we discussed regarding this question)

Answer 1

Not every organism follows the rules of human sex determination. Reason being not all organism have same number of chromosomes among mother and father so not really universal

Question 2

Usually only ______________ (number) is activated in each female mammal. Fill in the blank.

Answer 2

one

Question 3

The inactivated X chromosome of a female is highly condensed making it visible as an intensely staining ______________ attached to the nuclear membrane. Fill in the blank.

Question 4

Females that are heterozygous for X chromosome alleles are ______________. Their individual cells may express different alleles, depending on which chromosome is inactivated. Fill in the blank.

Question 5

Regarding synapsis of chromosomes, genetic recombination occurs less often between certain genes. Why?

Question 6

As distance between two genes on a chromosome ___________, the probability of recombination between them increases. Fill in the blank.

Question 7

Regarding changes in chromosomes, what is disjunction?

Question 8

What is the definition of (a) aneuploidy, (b) monosomy, or (c) trisomy?

Answer 8

(a) Aneuploidy is losing or gaining required number
(b) Monosomy is missing a chromosome (45)
(c) Trisomy is having an extra chromosome (47)

Question 9

Which statement describes an example discussed in class regarding X chromosomal genetic defects?

Question 10

Which statement describes an example discussed in class regarding Y chromosomal genetic defects?

Question 11

Which statement accurately describes how someone would receive either (a) sickle-cell disease, (b) hemophilia, or (c) Huntington’s disease?

Question 12

Know how to read a pedigree chart and be able to interpret the answers for (a) reading generations, (b) reading male from female, (c) knowing if someone has a disease, and (d) being able to figure out if the disease is recessive or dominant.

Question 13

According to the video Incomplete Dominance, Codominance, Polygenic Traits, and Epistasis, what is the definition of codominance?

Answer 13

the alleles work together

Question 14

According to the video Incomplete Dominance, Codominance, Polygenic Traits, and Epistasis, what would be the color of chicken offspring of BB (black) and WW (white) parents following codominance genetic rules? Why does this occur?

Answer 14

All of the offspring would be black and white “speckled” because both traits would show up (codominance)

Question 15

According to the video Incomplete Dominance, Codominance, Polygenic Traits, and Epistasis, what are polygenic traits?

Answer 15

“many” gene codes for one trait

Question 16

According to the video Incomplete Dominance, Codominance, Polygenic Traits, and Epistasis, both height and skin color can be influenced by ___________ factors. ____________ can affect your height and spending a lot of time in the sun can affect your ___________. However, it cannot affect your genetics for a trait. Fill in the blanks.

Answer 16

environmental; Nutrition; skin color