Mendelian

Question 1

Gregor Mendel

Answer 1

Austrian monk
- cross bred peas and found the same ratio of characteristics of every feature in every feature

Question 2

simple dominance

Answer 2

when 2 traits are crossed, one trait will appear much more often than the other

Question 3

alleles

Answer 3

a single copy of a trait
- 2 alleles per single gene

Question 4

dominant allele

Answer 4

if present, it will be expressed, even if there’s only 1

Question 5

recessive allele

Answer 5

2 copies to be expressed

Question 6

punnett square

Answer 6

a graphical way of showing the probability of gene expression in offspring

Question 7

genotypes

Answer 7

allele combinations, the letters

Question 8

phenotype

Answer 8

physical expression

Question 9

Y

Answer 9

dominant allele

Question 10

y

Answer 10

recessive

Question 11

YY

Answer 11

homozygous dominant

Question 12

Yy

Answer 12

heterozygous

Question 13

yy

Answer 13

homozygous recessive

Question 14

homologous chromosomes

Answer 14

a pair of the same numbered chromosome
ex: you have 2 chromosomes, 1 each has same genes but may have different alleles.

Question 15

simple dominance examples

Answer 15

• hitchhiker’s thumb
• widow’s peak
• clasped hands

Question 16

incomplete dominance

Answer 16

in heterozygous individuals, the recessive allele has minor influence
- as a result, there are 3 possible expression (phenotype)

Question 17

sickle cell trait

Answer 17

example of incomplete dominance in humans
A – normal hemogloblin
a – irregular hemoglobin
AA – normal red blood cells
aa – sickle cell disease
Aa – minor sickle cell

Question 18

heterozygous advantage

Answer 18

where negative traits stay in population due to survivability of people with heterozygous phenotype
ex: cystic fibrosis

Question 19

co dominance

Answer 19

one gene cross where there are multiple dominant expressions and a recessive expression
ex: ABO blood group
- A = dominant expression
- B = dominant expression
- AB = dominant expression
- O = recessive

Question 20

gene frequency

Answer 20

due to traits building up in population due to survivability of individuals

Question 21

autosomal traits

Answer 21

found on chromosomes 1-22
- gender does not influence inheritance
- genetic disorders are nearly always autosomal recessive – you’d need 2 versions of it

Question 22

sex linked trait

Answer 22

found only on the X chromosome
- males more likely to inherit than females
- either fully affected or not at all
- Males get it from their moyher

Question 23

pedigree

Answer 23

multi-generational way of showing how genetic traits can be inherited
- aa – express trait
- Aa – carrier