Question

number and a different sequence of amino acids?
a. proteins are produced by different ribosomes.
b. proteins are coded by genes with different nucleotide sequences.
c. proteins are different because each codon codes for more than one amino acid.
d. proteins combine in different ways based on the cellular need.
open response: a female lizard develops a mutation in a gene. she has an offspring that expresses a new form of a hereditary trait. based on these events, give two pieces of information about the new trait.

Explanation:

Multiple - Choice Question (about why different proteins have different amino acid sequences)

• Option a: Ribosomes are the site of protein synthesis, but different ribosomes don't produce different proteins in terms of amino acid sequence determination. So a is incorrect.
• Option b: Genes are made of DNA with nucleotide sequences. Different genes have different nucleotide sequences, and the nucleotide sequence of a gene codes for the amino acid sequence of a protein. So different genes (with different nucleotide sequences) code for proteins with different amino acid sequences. This is correct.
• Option c: The genetic code is degenerate (one amino acid can be coded by multiple codons), but this explains why different codons can code for the same amino acid, not why proteins have different amino acid sequences. So c is incorrect.
• Option d: The combination of proteins based on cellular need is about protein - protein interactions or protein function regulation, not about the amino acid sequence of proteins. So d is incorrect.

1. Inheritance of the Mutation: The new trait is due to a mutation in a gene of the female lizard. Since the offspring expresses the new trait, the mutation is likely in a germ - line cell (egg cell) of the female lizard. Germ - line mutations are passed on to offspring, while somatic mutations are not. So the offspring inherited the mutated gene from the mother.
2. Effect on Protein/Traits: The mutation in the gene likely changed the nucleotide sequence of the gene. This change in the gene's sequence can lead to a change in the amino acid sequence of the protein it codes for (if it's a coding gene). A change in the protein's amino acid sequence can alter the protein's structure and function. Since proteins are involved in determining traits (e.g., structural proteins, enzymes, signaling molecules), this altered protein can result in the new form of the hereditary trait in the offspring.

Answer:

b. Proteins are coded by genes with different nucleotide sequences.

Open - Response Question (about the new trait in lizard offspring)