Mendel's
Discoveries
Discoveries
What type of offspring results when two purebred pea plants with different traits are crossed?
Hybrid offspring.
What is the name for different forms of the same gene?
Alleles
What inheritance pattern produces a blended trait, such as red and white flowers producing pink flowers?
Incomplete dominance.
If B represents dominant black fur, what fur color would a rabbit with the genotype Bb have?
Black fur.
What process allows organisms with helpful adaptations to survive and reproduce more successfully?
Natural selection.
What do we call a trait that masks another trait?
A dominant trait.
What is an organism's physical or observable trait called?
Phenotype
What inheritance pattern produces offspring showing both traits without blending?
Codominance
A Tt plant is crossed with a tt plant. What percentage of offspring will be short?
50%.
What is a random change in allele frequencies within a population called?
Genetic drift.
What type of letters represent recessive alleles?
Lowercase letters.
What do we call an organism's genetic combination, such as Bb?
Genotype
What is it called when one gene has more than two possible alleles in a population?
Multiple alleles.
A PP plant is crossed with a Pp plant. What percentage of offspring will be hybrid?
50% (Pp).
Which population is more likely to be strongly affected by genetic drift: a population of 12 goats or a population of 10,000 goats?
The population of 12 goats.
If purebred green-pod plants are crossed with purebred yellow-pod plants and all offspring have green pods, which trait is dominant?
Green pods.
What does heterozygous mean?
Having two different alleles for a gene, such as Tt.
What is it called when two or more genes work together to produce one trait?
Polygenic inheritance.
Two heterozygous tall plants (Tt × Tt) are crossed. What percentage of offspring will be tall?
75%.
Why might foxes with larger ears become more common in a hot desert environment?
Larger ears can help release body heat, potentially improving survival and reproduction.
What happens to the two alleles for a gene when reproductive cells form?
They separate, so each reproductive cell receives one allele.
What is the difference between purebred and hybrid?
Purebred organisms have two identical alleles, while hybrid organisms have two different alleles.
What inheritance pattern occurs when a trait is controlled by one gene with two alleles and one allele masks the other?
Simple dominance.
Two heterozygous tall plants (Tt × Tt) are crossed. What is the genotypic ratio of their offspring?
1 TT : 2 Tt : 1 tt.
What is the main difference between natural selection and genetic drift?
Natural selection favors inherited traits that improve reproductive success, while genetic drift changes allele frequencies randomly.