Answer:
Sickle cell disease in an autosomal recessive inherited disease which is caused by the mutation in the HBB (hemoglobin-β gene) gene present on the chromosome no. 11. In sickle cell, the red blood cells become sickle shape due to the abnormal shape of hemoglobin present in it.
These sickle cells are known to form a blockage in the blood vessels thereby causing damage to the vital organs. Human spleen constantly destroys sickle cells because they get trapped in it which causes a disease called sickle cell anemia.
Sickle cell anemia is normally the problem in genetic disease which is inherited from the parents to children. When both the DNA strand has a mutation in their HBB gene then only this disease will affect the individual.
Changes depending on the gravity
Answer:
1. Each Giraffe's neck length is different
2. The tall neck Giraffes reproduced and their off spring inherited their genes
3. A drought occurred.
Explanation: