Heredity

Question 1

The karyotype diagram below represents a human female with the genetic disorder known as Turner syndrome.
Chromosomal analysis of this karyotype reveals the mutation is a result of

Answer 1

a missing X chromosome

Question 2

When roan cattle are mated, 25% of the offspring are red, 50% are roan, and 25% are white. Upon examination, it can be seen that the coat of a roan cow consists of both red and white hairs. This trait is one controlled by

Answer 2

codominant alleles

Question 3

A student studying feather color inheritance in a certain species of chickens observes that the chickens have black (homozygous), blue (heterozygous), or white (homozygous) feathers. The student hypothesizes that this feather color trait follows the incomplete dominance inheritance pattern.

Which data table would support the student’s hypothesis?

Answer 3

Parent 1- black feathers
Parent 2- white feathers
Offspring- blue feathers

Question 4

Plants have tissues that are active sites for cell division. One tissue is the apical meristem, which consists of embryonic cells that differentiate to form many different types of cells, like epidermal cells and mesophyll cells.

Which characteristic explains how these different types of cells found in the same plant can perform different types of functions?

Answer 4

They have different sets of genes that are active

Question 5

Which statement describes crossing over as it occurs in meiosis?

Answer 5

Homologous chromosomes exchange segments of DNA

Question 6

In labrador retriever dogs, the black coat color allele (B) is dominant over the chocolate coat color allele (b). However, some litters produce dogs that have a yellow coat color. Scientists have determined this is because of a second gene that can influence coat color. If this eumelanin gene is recessive for both alleles (e), the dog’s coat will be yellow regardless of the alleles for the other coat color gene.
A dog breeder sets up a cross between a dog that is homozygous dominant for coat color (BB) and heterozygous for eumelanin (Ee) with a dog that is homozygous recessive for coach color (bb) and heterozygous for eumelanin (Ee).
Use the Punnett square to determine what percent offspring would be expected to be yellow.

Answer 6

25%

Question 7

How could genetic engineering be used to produce a more successful crop in a hot, dry climate?

Answer 7

DNA from plants adapted to dry areas could be added to the genomes of the crop plants.