It's something to do with the fact that having sickle cell anaemia reduces the chances of contracting malaria, obviously a very common disease in Africa. I'm not quite sure what the link is but hopefully this helps a little bit?
The statement above is TRUE.
The electrochemical gradient in the chloroplast is a gradient of electrochemical potential of ions which move across the membrane of the chloroplast during the photosynthesis process. The proton gradient across the thylakoid membrane drives the ATP synthesis during photosynthesis.
Answer:True
Explanation:the electron transport chain can be considered to be an aerobic pathway because it utilizes free oxygen as its final electron acceptor. These free oxygen is liberated by intermediate glucose molecules.
The allele for dwarfism - D its dominant
Recessive allele -d
If the person has heterozygous alleles -Dd the person will have achrondroplastic dwarfism
However if the person if homozygous for the allele DD it’s Lethal and person can’t survive
If both parents are Dd
Dd X. Dd
Offspring DD Dd Dd dd
Probability of children who survive with the trait have the genotype Dd
Probability - 1/4 + 1/4
Probability of having surviving children with the trait -1/2 -0.5
Living organisms obtain many of their requirements by diffusion. They also get rid of many of waste materials in this way. For example, Plants need carbon dioxide for photosynthesis. This diffuses from the air into the leaves through the stomata. It does this because there is a lower concentration of carbon dioxide inside the leaf as the cells are using it up. Outside the leaf in the air, there is a higher concentration. Carbon dioxide molecules therefore diffuse into the leaf down this concentration gradient :)
I hope u understood!