Which of the following describes a dna mutation? a. the linking of free nucleotides into a long chain b. a change in the nucleotide sequence of a gene c. the packaging of dna into a structure called a chromosome d. the substitution of uracil for thymine in rna

B. A change in the nucleotide sequence of a gene APEX, i just answered it.

The correct answer is -

B. A change in the nucleotide sequence of a gene.

Mutation can be described as permanent change in the genetic material of living organisms (that is DNA, deoxyribonucleic acid).

In other words, it depicts change in the sequence of nucleotide within gene (a segment of DNA that codes for particular protein).

It can be caused due to error in the replication process or by the exposure to some chemical, physical or biological agents (that are known as mutagens, such as UV radiation).

Mutation can result in altered protein, if change is within the coding region.

There are primarily three types of mutation, which are substitution, insertion, and deletion mutation.

Thus, option B) is the right answer.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

this would be a math