Vocabulary
A white and red flower are bred together. Their offspring are all pink. What kind of dominance is being seen here?
Two tall heterozygous pea plants are crossed. (Tt)
What will the completed Punnett square of this cross look like?
What will the genotypes be?
What will the phenotypes be?
TT, Tt, Tt, tt
75% of tall pea plant
25% chance of short pea plant
Give one example of nature effecting ones traits and one example of nurture effecting ones traits. Explain the difference between the two.
Nature: Hair color, height, eye color, temper
Nurture: Personality, food preference, outside interests, critters diet affecting tail shape
What is reproductive success? Give one example of a trait that may affect an animals reproductive success.
Reproductive success is how successful animals are at reproducing.
EX: antler size, bird feather color, animal size, ability to win fights
Why is it impossible for offspring to show the recessive trait if one parent is homozygous for the dominant trait?
Because a dominant allele will always overpower a recessive allele.
Explain the difference between co-dominance and incomplete dominance. Give one example of each.
Co-dominance (Cooperation): both traits are seen separately.
EX: Black and white cow
Incomplete dominance (Mixing): Traits combine and a new trait is expressed.
EX: Pink flower w/ red and white parents
Would Punnett Squares be useful to predict the results of asexual reproduction? Explain your answer.
No. Asexual reproduction results in offspring that are clones of one another.
A scientist has some red-eyed fruit flies. She knows that red eyes are dominant over the white eyes in fruit flies. She wants to find out if the fruit flies she has are homozygous for the red eye color.
What cross will be best to find out if the red-eyed fruit flies are homozygous?
A dominant cross.
Dominant: RR, RR, RR, RR
Heterozygous: RR, RR, Rr, Rr
Recessive: Rr, Rr, Rr, Rr
What causes variation between offspring of the same parents?
Different allele combinations resulting in different phenotypes shown.