B) Hemoglobin is an oxygen-carrying protein found in red blood cells. Describe the structure of hemoglobin. C) Sickle-cell disease is a genetic disorder that causes red blood cells to become sickle shaped. Explain the cause of sickle-cell disease and the effects of the disorder on patients.

B) hemoglobin comprises for subunits each having one polypeptide chain in one heme group. all hemoglobins carry the same prosthetic heme group iron protoporphyrin IX associated with a polypeptide chain of 141(alpha) and 146 (beta) amino acid residues.

C)sickle cell anemia is caused by a mutation in the gene that tells your body to make the iron-rich compound that makes blood red and enables red blood cells to carry oxygen from your lungs throughout the body (hemoglobin).

Explanation:

Hope this helped Mark BRAINLEST

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.

d. planting trees

the trees take in carbon to make oxygen.