Lab 6

Question 1

Are females xx or xy?

Answer 1

xx

Question 2

are males xx or xy?

Answer 2

xy

Question 3

What is a karyotype?

Answer 3

a photograph of the chromosomes of an actively dividing cell, showing the number, shape, and size.

Question 4

how many pairs of autosomal chromosomes do people have?

Answer 4

22

Question 5

How many pairs of sex chromosomes do people have?

Answer 5

1

Question 6

What is turner syndrome?

Answer 6

it is when an x or a y is missing

missing a sex chromosome

Question 7

What is down syndrome?

Answer 7

trisomy 21

3 21 chromosomes

Question 8

What is Klinefelter’s?

Answer 8

2 x chromosomes and 1 y

Question 9

Does sex-linked mean they are related to sex?

Answer 9

no

Question 10

What chromosome are sex-linked genes found on?

Answer 10

x chromosome.

Question 11

Are males or females more likely to have a sex-linked trait?

Answer 11

males

Question 12

Do heterozygous females display a sex linked trait?

Answer 12

no. they are called carriers.

Question 13

What deficiency causes red-green color blindness?

Answer 13

deutan (can’t see red) and protan (can’t see green)

Question 14

What are polygenic traits?

Answer 14

phenotypic traits that involve contributions from the alleles of many genes at multiple locations and on separate chromosomes.

Question 15

What are 4 examples of polygenic traits?

Answer 15

IQ, human height, skin pigmentation, total yields of crop varieties, production level of milk in cattle.

Question 16

What is the distance between two genes measured in?

Answer 16

map units

Question 17

Hoe do you find map units (% recombination)?

Answer 17

total # of recombinants
___________________ x 100
total # of offspring

Question 18

What numbers are considered the recombinants?

Answer 18

The two lowest numbers

Question 19

How are recombinant gametes formed?

Answer 19

When crossing over occurs

Question 20

What does a graph for a polygenic trait look like?

Answer 20

an upside down “U”