Answer:
Structural adaptations are physical features of an organism like the bill on a bird or the fur on a bear. Behavioral adaptations are the things organisms do to survive. For example, bird calls and migration are behavioral adaptations.
An electron transport chain pumps protons across a membrane while transferring electrons from one chemical to another.
It’s D (example a turtle draws its head back into its shell when it’s shell is touched) I’d say it’s kinda of the same as odor (if u already answered it then dang)
The red blood cell is normally circular shaped but for sickle cell anemia the red blood cell is literally sickle shaped so the surface area decreases and less amount of oxygen is stored by the sickle shaped cell thus resulting in low O2 content
