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1

when maternal and paternal chromosomes pair and physically exchange DNA segments

recombination

2

alleles of different genes are distributed independently of one another; maternal and paternal chromosomes line up next to each other along the midline of the cell and segregate into newly forming cells ;
pairs can line up in different ways

independent assortment

3

an allele that affects phenotype only if the organism has two copies of that allele; hidden by normal or dominate allele

recessive allele

4

two different alleles (Aa)
-phenotype is normal
-individual is a carrier

heterozygote

5

two identical alleles

homozygote

6

an individual will carry the recessive allele for CF, but will not have the disease because the alleles effect is masked by the dominate alleles

heterozygous carrier

7

an individual who is heterozygous for a particular gene of interest and therefore can pass on the recessive allele without showing any of its effects

carrier

8

a diagram to determine the probabilities of offspring having particular genotypes
based on genotypes of the parents
; matches up all possible gametes

punnett square

9

sex hormones are produced by ________

gonads

10

what are gonads

ovaries in females, testes in males

11

androgens

testosterone:males , estrogen: females

12

humans have 23 pairs of chromosomes
22 pairs are _______ and 1 pair are ________

autosomes and sex chromosomes

13

paired chromosomes present in both males and females; all chromosomes except the X and Y chromosomes

autosomes

14

paired chromosomes that differ between males and females, XX in females, XY in male

sex chromosomes

15

in the absence of a y chromosome, a fetus will develop into a

female (XX) (males are XY)

16

fathers determine

the sex of the baby

17

a phenotype that is determined by allele on an X chromosome

x-linked trait

18

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

recessive x linked trait

19

a visual representation of the occurrence of phenotypes across generation

pedigree

20

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

incomplete dominance

21

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

codominance

22

blood type alleles A and B are

codominant

23

blood type o is ____to both A and B

recessive

24

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

polygenic trait

25

failure of chromosomes to separate during cell division

nondisjuction

26

an abnormal number of one or more chromosomes

aneuploidy

27

sex determination has what aspects

GHAB
Genetic, Hormonal, Anatomical, Behavioral

28

a persons phenotype is determined by both __genes___ and environmental influences this is described as

multifactorial