1
What word means the passing of traits from parents to offspring?
heredity
Go to the board and complete a Punnett square for the following scenario:
A heterozygous tall plant is crossed with a homozygous recessive short plant.
What are the possible heights of the offspring?
(use letter Tt to show)
answer will be shown on board
Go to the board and draw a Punnett square to answer the following question:
A homozygous dominant purple-flowered plant is crossed with a heterozygous purple-flowered plant.
Purple is dominant
White is recessive
What percentage of a chance is there that the new flower will be purple?
(use letters Ff)
answer will be shown on board
In a Punnett square, where do you place the male parent's alleles?
across the top of the square
Explain why two heterozygous parents might produce some offspring that show a recessive phenotype.
Each parent can pass the recessive allele; if an offspring receives the recessive allele from both parents (rr), the recessive phenotype appears.
Which allele notation is used for dominant alleles and which for recessive alleles
Uppercase letters for dominant; lowercase letters for recessive
What is the scientific term for a trait that is visible or how a trait appears (e.g., blue eyes)?
phenotype
Go to the board and draw a Punnett Square to answer the question:
Yellow kernels are dominant over white kernels.
Two heterozygous corn plants are crossed.
What ratio of yellow to white kernels would you expect?
answer will be corrected on board
Who is known as the father of genetics for his pea plant experiments?
Gergor Mendel
What is the term for different forms of a gene?
allele
If you can observe the trait (like blue eyes), is that phenotype or genotype?
phenotype
Name the term for the young of an animal or plant.
offspring
What is the term for the two alleles that control a trait (the genetic makeup), which you cannot directly see?
genotype
What word describes a genotype with two identical alleles (for example, RR or rr)?
homozygous
Mendel proposed that each parent contributes one "factor" for each trait. What modern structure did later scientists identify as carrying these factors?
chromosomes (or genes on chromosomes)
What word describes a genotype with two different alleles (for example, Rr)?
heterozygous
Using the same Yy × Yy cross, what is the phenotype ratio (yellow : green) if yellow is dominant?
3:1
What do geneticists call a section on a chromosome that contains information for one trait?
gene
What term describes a genetic factor that is blocked by a dominant factor and only shows when two copies are present?
recessive trait
What model uses a grid to predict possible genotypes and phenotypes of offspring?
Punnett square