Genetics: Punnett Squares and Likelihood

What is a Punnett Square?

• A diagram used to predict the outcome of a genetic cross by showing the possible combinations of alleles from the parents.

• A tool for measuring the height of plants in genetics studies.

• A method for calculating the age of fossils in paleontology.

• A chart used to track the migration patterns of animals.

What does it mean for an organism to be homozygous?

• An organism has two different alleles for a specific gene.

• An organism has one allele for a specific gene.

• An organism has two identical alleles for a specific gene.

• An organism has no alleles for a specific gene.

How do you determine the likelihood of a specific phenotype in offspring?

• By analyzing the Punnett Square and counting the number of times the phenotype appears.

• By observing the parents' traits and predicting the offspring's traits based on them.

• By conducting a genetic test on the offspring after they are born.

• By estimating the phenotype based on environmental factors affecting the parents.

What is the expected genotype ratio from a cross between two heterozygous parents (Tt)?

• 1 TT : 2 Tt : 1 tt

• 1 TT : 1 Tt : 2 tt

• 3 TT : 1 Tt : 1 tt

• 1 Tt : 1 tt

What is the purpose of a Punnett Square in genetics?

• To visualize and calculate the probability of offspring inheriting particular traits.

• To determine the exact traits of the offspring.

• To analyze the genetic makeup of a population.

• To create a genetic map of an organism.

What is the genotype of a homozygous recessive organism?

• TT

• Tt

• tt

• tT

What does it mean for parents to be heterozygous for a trait?

• It means that both parents carry one dominant and one recessive allele for that trait.

• It means that both parents carry two dominant alleles for that trait.

• It means that both parents carry two recessive alleles for that trait.

• It means that one parent carries a dominant allele and the other carries a recessive allele.

What is the expected outcome if one parent is homozygous recessive (tt) and the other is heterozygous (Tt)?

• 25% tall (TT) and 75% short (tt)

• 50% tall (Tt) and 50% short (tt)

• 100% tall (Tt)

• 75% tall (Tt) and 25% short (tt)

What is the significance of the letter 'B' in genetics?

• It represents a recessive allele.

• It represents a dominant allele.

• It indicates a mutation in the gene.

• It is used to denote a sex-linked trait.

What is the genotype of a heterozygous organism?

• TT

• tt

• Tt

• TTtt