AP BIOLOGY

Detailed explanation-1: -Sometimes, gene variants (also known as mutations) prevent one or more proteins from working properly. By changing a gene’s instructions for making a protein, a variant can cause a protein to malfunction or to not be produced at all.

Detailed explanation-2: -A genetic mutation is a change to a gene’s DNA sequence to produce something different. It creates a permanent change to that gene’s DNA sequence. Genetic variations are important for humans to evolve, which is the process of change over generations. A sporadic genetic mutation occurs in one person.

Detailed explanation-3: -Silent mutations occur when the change of a single DNA nucleotide within a protein-coding portion of a gene does not affect the sequence of amino acids that make up the gene’s protein.

Detailed explanation-4: -Harmful mutations may cause genetic disorders or cancer. A genetic disorder is a disease caused by a mutation in one or a few genes. A human example is cystic fibrosis. A mutation in a single gene causes the body to produce thick, sticky mucus that clogs the lungs and blocks ducts in digestive organs.

Detailed explanation-5: -A gene mutation is the change in the base sequence of DNA that results in the formation of a new allele. It has no effect because the genetic code is degenerate, does change the amino acid but no effect on the tertiary structure, the new allele is recessive so it doesn’t influence the phenotype.