The correct answer is (d.) proteins. Higher organisms use nitrogen to make their protein. Food that is containing protein also involves nitrogen in it. Protein also has amino acids that contain nitrogen in it which is a necessary essential nutrient for the body.
<span>the main difference between the two is ivertebrates doesnt have no backbone or spinal cord... vertebrates do have a back bone like humans</span>
Receive deoxygenated blood from the body
Messanger RNA cuz it gives the "messages"... thats how i remembered it in school lol
