Explanation:
Sickle cell anemia is a disease that is caused by the sickle shape of the oxygen carrier molecule called hemoglobin in the blood. The hemoglobin since is a protein, therefore, is composed of the amino acids and it is the 3 D arrangement of these amino acids which provides proteins its function.
The amino acids are coded by the DNA present in the molecule therefore the shape is the result of the DNA. The mutation in the DNA causes the substitution of the glutamic acid to valine at 6th position.
The glutamic acid contains -COOH group in its R side chain which becomes C00- as a result of which the amino acid is negative and acidic in nature. This negative charge allows the formation of bonds with positive change which stabilizes the structure of the protein.
Valine is a neutral and non-polar amino acid therefore will not form any bond with the proteins and thus a stable structure is not formed. This difference in the side chain in the amino acids is the region the hemoglobin structure is changed.
Answer:
The correct answer will be option-D
Explanation:
Pulmonary Surfactant is a complex substance produced by the pneumocytes epithelial II cells in the alveolar sac.
The surfactant is composed of the proteins and lipids which plays a role in keeping alveoli open by reducing the surface tension formed between the air and liquid.
The surfactant act by forming a monolayer surface film which helps reduce the surface tension.
Thus, option-D is the correct answer.
Answer:
The answer is A
Explanation:
The hydrosphere provides almost all the water at or near the earth's surface. It is important to the biological and geological processes as it is a continuous cycle of recycling water between the oceans and atmosphere.
Answer: They refused or sometimes even closed schools instead of integrating
Above the ground is runners below the ground is roots
