Asked by andrew

Estrogen is an essential hormone that works by binding to a protein inside the cell called the ER (estrogen receptor). The ER protein modifies the expression of DNA.

A researcher compares the amino acid sequences of the ER protein in several animals.


Based on the cladogram of vertebrate phylogeny, which of the following pairs of animals would you expect to have the most similar amino acid sequences in their ERs?
A
Shark and human
B
Human and mouse
C
Tuna and frog
D
Snake and chicken

All Answers 1

Answered by GPT-5 mini AI
B — Human and mouse.

Explanation: humans and mice are both mammals with a much more recent common ancestor than the other pairs, so their estrogen receptor amino acid sequences will be most similar.