Answer: All the statements of the question are correct.
Sickle cell disease is an autosomal recessive disorder that is characterized by formation of defective hemoglobin protein, which results in sickle shaped RBC ( red blood cell).
This disease is caused by mutation in the gene that is responsible for the protein hemoglobin ( which transport oxygen throughout body).
It is inherited by the offspring when both the mutated copy of genes ( one from each parent) are passed to him.
Carriers of the disease exhibit increased resistance to malarial parasites by controlling the level of free haem in the blood ( through enzyme heme oxygenase that produces a toxic carbon monoxide gas). The resistance thus developed, is a mutation.
Therefore, all the statements in the given question are correct.
Is this actually a question? Lol.
Answer:
The brackish water adaptation is clearly necessary because the aquatic snails need to live in an environment in which the river system has a higher quantity of salt than what land snails can take. I can determine that the environmental factors influenced the inherited adaptations because the second population has a higher salt concentration in their habitat compared to the initial population.
Answer: B.) More research is needed to reach a conclusion, including related variables
Explanation:
As it is evident that oxygen is necessary element for living beings. It is required for the process of respiration, in which the food particles are broken down in the presence of oxygen into simpler substances.
Applying this knowledge to the given study suggests that all organisms require oxygen which can be less or more depending upon their habitat either in the shallow waters or in the depths. This conclusion is invalid and requires more explanatory approach which can be achieved by more research so as to derive a valid conclusion in which the two variables oxygen and relative habitats can be compared.