If a base-pair change occurs during dna replication, this

is a mutation.
would be a mutation only if it falls in a protein-coding part of a gene.
would be a mutation only if it falls in a transcribed part of the genome.
is not a mutation, because only one base pair has been altered.

Correct "is a mutation"

This is the best answer choice because a mutation when at least one base pair changes to another.

Incorrect Answers:

"would be a mutation only if it falls in a protein-coding part of a gene"

Some mutations are more influential than others. If this mutation occurred in a region that codes for a protein, then it could greatly influence the structure/function of the the protein and therefore the cellular processes that the protein is used for. Oppositely, mutations can occur in regions that don't code directly for a protein and therefore could go completely unnoticed, making this a bad answer choice.

"would be a mutation only if it falls in a transcribed part of the genome."

A mutation can occur when the gene in transcribed from DNA → RNA, but the process of transcription is separate from that of DNA replication so that makes this answer choice not so good.

"is not a mutation, because only one base pair has been altered."

A mutation can be just when one base pair is altered, so this is an incorrect statement.

i think it would be b. tissue because an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.

water is a polar molecule. a chemical bond is a force of attraction between atoms or ions. bonds form when atoms share or transfer valence electrons. atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. so, false

explanation:

in h2o molecule, two water molecules are bonded by a hydrogen bond but the bond between two h - o bonds within a water molecule are covalent. the greater the electronegativity difference, the more ionic the bond is. bonds that are partly ionic are called polar covalent bonds. nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.