Unit 9: Genetics Flashcards
character = ?
which one is mendel / modern
examples?
character (mendel) = gene (modern)
- height, eye color
trait = ?
which one is mendel / modern
examples?
trait (mendel) = allele (modern)
- tall/short
what are genotypes?
alleles inherit from parents (Tt, pp)
purebred = ?
which one is mendel / modern
purebred (mendel) = homozygous (modern)
what is homozygous?
both alleles the same -> TT/tt
what is heterozygous>
2 diff alleles, 1 dom 1 recessive -> Tt
heterozygous = hybrid
what are the 4 rules of Mendelian genetics?
- there are 2 possible alleles (traits) that affect 1 SINGLE phenotype in each gene
- alleles (traits) separate during meiosis
- individual inherits one allele (trait) from each parent per gene (character)
- dominant alleles are completely dominant over recessive alleles (traits)
What is Incomplete Dominance? examples?
heterozygous have 之間的 dom/recessive
ex: snapdragon flower
- Red (R) incomplete dominant
- White (r) recessive
→ PINK FLOWERS
What is Codominance? examples?
COllaborate
2 alleles for same gene EQUALLY DOMINANT
ex: ABO blood type equal amount of A&B antigens
What is Polygenic Inheritance? examples?
poly = many
→ 2+ genes affect 1 phenotype (looks)
ex: human skin determined by 3 diff genes (show continuous variation)
What is phenotype?
appearance caused by alleles inherited
What is Multiple Alleles? examples?
3+ alleles for a single gene
ex:
- A, B, O alleles for human blood
- 5 diff alleles (types) of fruit fly wings
What is X - Linked Genes? examples (3)?
gene carried ONLY in X chromosome
ex: (all female carriers cause recessively inherited)
1. human baldness
2. red - green color blindness
3. hemophilia
What is Lethal Genotypes? examples?
genotype that prevents fetus from developing
ex: lethal when….
- dwarf allele (D) when homozygous
- star eye (S) alele in fruit flies when homozygous
2 homozygous recessive + +
WILDTYPE