In humans, the allele n causes an abnormal shape of the patella in the knee (n is the normal allele). a separate gene is concerned with finger length the allele b causes abnormally short fingers, whereas b gives normal length. a study focused on people who have abnormal patellae and short fingers (n/n. b/b in genotype), having inherited the n allele from one parent and the b allele from the other parent. these n/n. b/b people mated with normal spouses producing 40 progeny, classified as follows:
normal 3
abnormal knees and fingers 2
abnormal knees only 17
abnormal fingers only 18
what ratios of parental and recombinant phenotypes would you expect if these genes are linked? unlinked?
use a chi-square test to check if the genes are linked. if they are, provide a map distance for these two genes.

the answer is d (apex) good luck : ))

one is through turgidity. this occurs before ground tissue ( collenchyma

and sclerenchyma cells) become well

developed to give structural support to the plant as it grows bigger. the xylem

tissue (composed of rigid tissue) of the young

plant render this support and also maintaining osmotic turgidity of the surrounding

plant cells.

is this for the e2020 class

an individual’s sex (i.e., whether they are a male or female) is determined by the sex chromosomes. most people have two sex chromosomes, one that is inherited from their mother and one that is inherited from their father. typically, females have two x chromosomes (xx) and males have one x chromosome and one y chromosome (xy). conditions caused by changes (“mutations”) in genes located on the x chromosome are considered x-linked.

x-linked recessive inheritance

most x-linked conditions are recessive. this means that in a person with two x chromosomes (most females), both copies of a gene (i.e., one on each x chromosome) must have a change or mutation whereas in a person with one x chromosome (most males), only one copy of a gene must have a mutation. a female with a mutation in one copy of a gene on the x chromosome is said to be a “carrier” for an x-linked condition. a male with a mutation in a gene on the x chromosome is typically affected with the condition. because females have two copies of the x chromosome and males have only one x chromosome, x-linked recessive diseases are more common among males than females. however, x-linked recessive diseases can occur in both males and females.

for x-linked recessive disorders, an unaffected carrier mother who has a mutation in a gene on the x chromosome can transmit either the x chromosome with this mutation or a “normal” x chromosome to her children. if the father is unaffected, none of her daughters will be affected and all of her daughters will be unaffected—since they will inherit at least one normal x chromosome from their father. however, each daughter will have a 50% chance of being an unaffected carrier like her mother and a 50% chance of both x chromosomes being normal.