Genetics

Question 1

Genetics

{ 2 types of chromosomes}

Answer 1

• allows us to look at traits (DNA/Genetics) that are passed from parent to off spring.
• [need to work backwards]
• {Autosomes , Sex Chromosomes}

Question 2

Autosomes

Answer 2

• all chromosomes except sex chromosomes

- Determines most of the traits (22 pairs)

Question 3

Sex Chromosomes

Answer 3

• X or Y chromosomes.
• Determine sex of child
• 23 total = 1 pair sex chromosomes, 22 pairs autosomes
• XX = female
• XY = male

Question 4

Genotype

Answer 4

Refers to genetic make-up

Question 5

Phenotype

Answer 5

Refers to physical apperance

Question 6

Homozygous [ 2 types]

Answer 6

• Homozygous Dominant
  *contains 2 copies of the
  dominant gene : AA
  -Homozygous Recessive
  *contains 2 copies of the
  recessive gene : aa

Question 7

Heterozygous

Answer 7

• contains :

1 dominant + 1 recessive gene : Aa

Question 8

Dominant Gene

Answer 8

is usually expressed

Question 9

Recessive Gene

Answer 9

is usually masked unless it is homozygous parent generation

Question 10

Filial Generation

Answer 10

• off spring from a mating
• parent generation
  ex: F1,F2

Question 11

Genes

Answer 11

DNA / Traits

Question 12

True Breeding / Pure Breeding

Answer 12

Refers to a parent that is homozygous dominant or homozygous recessive

Question 13

Monohybrid Cross

Answer 13

• Looking at passage of a single trait

- proves the theory of gene segregation

Question 14

Dihybrid Cross

Answer 14

• Looking at passage of 2 traits

- illustrates the theory of independent assortment

Question 15

Testcross (Backcross)

Answer 15

• Done when genotype of parent with dominant trait is unknown
• That parent is crossed with a parent that is recessive for that trait
• the cross of an F1 heterozygote with a partner having the same genotype as one of its parent

Question 16

Carrier

Answer 16

A heterozygote has :

1 dominant + 1 recessive gene

Question 17

Punnett Square

Answer 17

Matrix used to determine possible outcome from cross

Question 18

Father of Genetics

Answer 18

Gregor Mendel

Question 19

Theory of Gene Segregation

Answer 19

• diploid organisms inherit 2 genes per trait on pairs of chromosomes.
• Each gene segregate from the other during meiosis such that each gamete will receive only one gene per trait.

Question 20

Theory of Independent Assortment

Answer 20

• states that meiosis ends
• genes on pairs of homologous chromosomes have assorted independently of each other so that gametes contain all possible combinations of alleles

Question 21

Incomplete Dominance

Answer 21

• a dominant allele cannot completely mask the expression of another allele.
• blending of 2 new phenotype

Question 22

Co-dominance

Answer 22

• Both alleles are expressed in heterozygotes

Question 23

Sex linked Genes

Answer 23

• Genes that are found on the X or Y chromosome
• mainly found on the X chromosome
• will be expressed in males
• expressed in female if they have 2 copies of the gene.
• females are homogametic (XX)
• males are heterogametic (XY)