Unit 9 Vocabulary

Question 1

a segment of DNA that codes for a particular trait

Answer 1

Gene

Question 2

an inherited characterisitic (ex. eye color)

Answer 2

Trait

Question 3

one set of chromosomes from mom and one set from dad that form a pair

Answer 3

Homologous chromosomes

Question 4

different versions (alternate forms) for a gene at a single location in the DNA

Answer 4

Allele

Question 5

observed trait of a organism that masks any other allele

Answer 5

Dominant

Question 6

masked by a dominant allele

Answer 6

recessive

Question 7

two copies of the dominant allele

Answer 7

Homozygous dominant

Question 8

one dominant and one recessive allele

Answer 8

heterozygous

Question 9

two copies of the recessive alleles

Answer 9

homozygous recessive

Question 10

the appearance of an organism for a gene

Answer 10

phenotype

Question 11

the inherited allele combination of an organism for a gene

Answer 11

genotype

Question 12

the passing of characteristics from generation to generation

Answer 12

heredity

Question 13

the passing on of traits from parent to offspring

Answer 13

inheritance

Question 14

the father of genetics; worked with pea plants

Answer 14

gregor mendel

Question 15

a genetic mating of individuals that are different for only 1 trait (tall vs. dwarf)

Answer 15

monohybrid cross

Question 16

the parental generation

Answer 16

p generation

Question 17

the first generation of offspring

Answer 17

F1 generation

Question 18

the second generation of offspring

Answer 18

F2 generation

Question 19

eggs or sperm

Answer 19

gametes

Question 20

alleles are randomly placed into gametes during meiosis

Answer 20

mendel’s law of segregation

Question 21

alleles are inherited independent from other alleles

Answer 21

mendel’s law of independent assortment

Question 22

an easy short hand way to predict the outcome of crosses

Answer 22

punnet square

Question 23

homozygous individual that can only make one type of allele

Answer 23

pure breeding

Question 24

the offspring from two different pure breeding parents

Answer 24

hybrid

Question 25

the predicted frequency of offspring genotype from a monohyrbid cross

Answer 25

genotype ratio

Question 26

the predicted frequency of offspring phenotype from a monohyrbid cross

Answer 26

phenotype ratio

Question 27

traits that require one dominant allele to be expressed; recessive phenotype requires two recessive alleles to be expressed

Answer 27

simple dominant/ recessive heredity

Question 28

genetic disorder caused by a dominant allele; individuals have shortened arms and legs

Answer 28

dwarfism

Question 29

genetic disorder caused by a dominant allele; degenerative neurological disorder

Answer 29

huntington disease

Question 30

genetic disorder caused by a recessive allele; fat builds up in baby's brain, killing the baby by age 5

Answer 30

Tay-sach's

Question 31

genetic disorder caused by a recessive allele; individuals cannot digest the amino acid phynlalanine

Answer 31

PKU

Question 32

disorder caused by a recessive allele; individuals accumlate thick mucus in the lungs

Answer 32

cystic fibrosis

Question 33

disorder caused by a recessive allele; individuals do not contain pigment in their cells

Answer 33

Albinism

Question 34

heterozygous displays a phenotype that is intermediate between dominant and recessive

Answer 34

incomplete dominance

Question 35

more than 2 alleles within the population for a particular gene

Answer 35

multiple alleles

Question 36

when 2 alleles are equally dominant, making an individual that expresses BOTH phenotypes

Answer 36

codominance

Question 37

genes that are on the X or Y chromosome, like colorblindness

Answer 37

sex linked

Question 38

sex linked disorder; individuals see colors differently

Answer 38

colorblindness

Question 39

sex linked disorder; individuals cannot clot blood properly

Answer 39

hemophilia

Question 40

sex linked disorder; individuals have mental and physical deformities (like an elongated head)

Answer 40

fragile x syndrome

Question 41

traits that are controlled by more than one gene

Answer 41

polygenic

Question 42

change in chromosome number

Answer 42

anueploidy

Question 43

failure of chromosomes to separate accurately during meiosis

Answer 43

nondisjunction

Question 44

disorder caused by aneuploidy with an extra chromosome #21

Answer 44

down syndrome

Question 45

disorder caused by aneuploidy with a missing x chromosome

Answer 45

turner syndrome

Question 46

discrete package of DNA that codes for genes

Answer 46

chromosome