Answer:
Trans-membrane proteins.
Explanation:
Membrane proteins are proteins that are found in the cell membranes of living organisms.
Hope this helped!
Birds, just like humans, have a four-chambered heart.
Its is possible because your previous family members like grandparents can have dimples special features like eye color can skip a generation so for example my family all have brown eyes and my mom previously had twins with blue eyes but my great grandma has blue eyes a feature skipped from my family and she got it from my elders
