The hemoglobin holoenzyme (active enzyme) is a complex of an iron ion and 4 subunits- 2 hemoglobin alpha and two hemoglobin beta. People with sickle cell disease have mutated beta hemoglobins. The mutation is a single nucleotide exchange, that changes the 6th amino acid of protein primary struture - a Glutamic acid into Valine. This one alteration changes the tree dimentional structure of hemoglobin beta so, that it forms lond fibres that disrupt the normal circular form of the red blood cells.
<span>The correct answer is that he has injured one of the tendons or ligaments that help keep his knee in place, connecting it to the surrounding muscle and bone. As a result of this injury, his knee is no longer connected to the muscle and bone, thus it wobbled sideways when he started walking. He needs to go to a doctor immediately who can fix his knee so as to prevent further complications - he just needs his knee to be set in place again.</span>
Breathing is an essential part of the works of the body. If you go a long time without breathing, you’ll die. The reason why you can go a long time without eating is because your body stores the fat to keep you going. Breathing is kind of the building block of the body.
The answer would be letter a
