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Flashcards in lecture 2/1/16 Deck (36)
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1

which of the following most influences the development of a female fetus?

- BC
the precedence of any two X chromosomes
the presence of a y chromosome

2

if a man has an x- linked recessive disease, can his sons inherit that disease from him?

-no, all his sons inherit their x chromosomes maternally

3

why do some people have unusual chromosome combinations, such as XYY and XXX

-errors occurred in chromosomes segregation during meiosis in their fathers or mothers

4

which of the following inheritance patterns includes an environment contribution

-multifactorial

5

how is co-dominant inheritance different from incomplete dominant inheritance?

- in codomincance two alleles are expressed equally; in incomplete dominance neither the dominant or recessive phenotypes seen in heterozygotes

6

what determines biological sex?

Sex hormones produced by gonads

7

sex hormones are produced by what

gonads

8

in a fetus, sex hormones shape development of ______________

sexual anatomy

9

humans have _____pairs of chromosomes

23

10

out of 23 chromosomes 22 pairs are ______

autosomes

11

in the absence of a Y chromosome, a fetus will

develop into a female

12

females are

XX

13

males are

XY

14

sons inherit Y chromosome from the _____

father

15

sons inherit X chromosome from the _____

mother

16

SRY gene on ______chromosome signals testes to develop

Y

17

testes produce ____

testosterone

18

if the sperm has an x chromosome, an embryo will usually develop __________

female sexual organs

19

ovaries produce

estrogen

20

a phenotype that is determined by allele on an X chromosome

x linked trait

21

normal copy on one X chromosome masks the recessive disease allele on the other x chromosome

recessive x linked trait

22

a male has a single x chromosome so he will show the effect of any recessive allele located on his

x chromosomes

23

a family tree where you can track the traits; a visual representation of the occurrence of phenotypes across generations

a pedigree

24

very small and few genes; study ancestry and identify paternity

y chromosome

25

a form of inheritance in which heterozygotes have a phenotype that is intermediate between homozygous dominant and homozygous recessive

incomplete dominance

26

three blood group alleles : A,B, and O
genotypes: OO, AO, BO, AB,AA , and BB

blood types

27

both maternal and paternal alleles contribute equally and separately to the phenotype

codominance

28

blood type alleles A and B are codominant . O is ________ to both A or B

recessive

29

a single straight determined by the interaction between alleles of more than one gene; i.e. human height

polygenic trait

30

height shows

continuous variation