Dihybrid Crosses and Genetic Traits

The video tutorial explains how to solve dihybrid crosses, which involve two traits at a time, illustrating the law of independent assortment. It covers two problems: one with wolf coat and eye color, and another with pepper plant fruit color and shape. The tutorial demonstrates how to determine possible gametes, fill out a Punnett square, and interpret the results to find genotypic and phenotypic ratios.

What is the primary purpose of using dihybrid crosses?

• To show the dominance of traits

• To predict the phenotype of a single trait

• To demonstrate the law of independent assortment

• To illustrate the law of segregation

In the first problem, what are the dominant traits for wolves?

• Black coat and blue eyes

• Normal coat and blue eyes

• Normal coat and brown eyes

• Black coat and brown eyes

How is the genotype of the alpha male wolf described?

• Big N little n, Big B little b

• Little n little n, little b little b

• Little n little n, Big B Big B

• Big N Big N, Big B Big B

What is the process used to determine the gametes for the female wolf?

• Pairing dominant alleles only

• Using the FOIL method

• Random selection of alleles

• Crossing the first trait with the second

What is the significance of keeping dominant alleles before recessive ones in the Punnett square?

• It changes the outcome of the cross

• It is a requirement of Mendel's laws

• It makes the results easier to read

• It ensures all possible combinations are covered

What percentage of offspring will be normal colored with blue eyes in the first problem?

• 50%

• 25%

• 100%

• 75%

In the second problem, what are the dominant traits for pepper plants?

• Red fruit and round shape

• Green fruit and round shape

• Red fruit and square shape

• Green fruit and square shape

What is the genotype of the pepper plants used in the second problem?

• Big G Big G, Big R Big R

• Little g little g, little r little r

• Big G little g, Big R little r

• Big G Big G, little r little r

Why is it unnecessary to determine gametes again for the second parent in the pepper plant problem?

• The second parent is not involved in the cross

• The second parent has no dominant traits

• The second parent is identical to the first

• The second parent is homozygous

What is the expected outcome when crossing two heterozygous pepper plants?

• All offspring will be identical

• The greatest variety of offspring will be produced

• There will be no variety in offspring

• Only recessive traits will be expressed