Explain how substitution, insertion, and deletion mutations are similar and different from one another.

Substitution:

Substitution is the switch of codons. A C could be switched to an A, but the original is now substituted for the new codon. This can change the amino acid present or it can be a silent mutation. If the stop codon is switched in, the protein will be cut short and the effects could be very serious.

Insertion:

Insertion is where base pairs are inserted into the DNA. This is different from substitution because nothing is getting switched out, just new ones are getting inserted. The original codons will still be present, just new ones are coming in. Insertions result in a frame-shift, which means everything after the mutation is shifted and nothing will be correct after this. Insertions are more harmful than substitution because it doesn't affect just one amino acid, but many.

Deletion:

Deletion is where some codons or DNA is deleted. This will result in everything after the mutation being incorrect and can cause drastic effects. Deletion is very similar to insertion because they both cause a frame-shift, but also very different because they do the opposite from one another. Deletion is also more harmful than substitution because of the frame-shift and the change in future amino acids.

correct answer is a. and d.

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.