Question

multiple choice 20 points
how do protein sequences provide evidence for common descent?
by showing that all organisms have different proteins.
by showing the shapes of bones
by examining embryo size.
by showing similarities in amino acid sequences among species.

multiple choice 20 points
genetics supports the theory of common descent because:
genes do not change over time.
genetic information is not inherited.
dna sequences are completely unique for every species.
dna sequences show patterns of similarity that reflect evolutionary relationships

Explanation:

• Question 4: Protein sequences are made of amino acids. Similar amino - acid sequences among species suggest a common evolutionary origin. Different proteins in all organisms (first option) would not support common descent. Bone shapes (second option) are related to comparative anatomy, not protein sequences. Embryo size (third option) is related to embryology, not protein - sequence evidence.
• Question 5: DNA sequences show patterns of similarity. If genes did not change over time (first option), evolution would not occur. Genetic information is inherited (so second option is wrong). DNA sequences are not completely unique for every species (third option is wrong), as similarities exist which reflect evolutionary relationships as per the theory of common descent.

Answer:

1. By showing similarities in amino acid sequences among species.
2. DNA sequences show patterns of similarity that reflect evolutionary relationships.