Answer:
Energy (in the form of ATP)
Explanation:
The main difference between active transport and passive transport is that active transport needs the energy to work. Active transport also moves molecules against the concentration gradient, kinda like a pump. This pump will need energy in the form of adenosine triphosphate (ATP) to keep it working. Adenosine triphosphate will be broken down into adenosine diphosphate (ADP). The energy from the breakdown reaction will be used by the pump.
An electron transport chain (ETC) is a series of complexes that transfer electrons from electrondonors to electron acceptors via redox (both reduction and oxidation occurring simultaneously) reactions, and couples this electron transfer with the transfer of protons (H+ ions) across a membrane.
After hundreds or even thousands of generations both alleles for sickle cell anemia are still common in those of African ancestry. This is supported by two mechanisms: heterozygote advantage and gene flow.
Heterozygote advantage
When an allele is said to be heterozygous, it is carrying one copy of a gene. For example if one carries a copy of sickle cell allele, it will stay in the population even after many generations — natural selection will not be able to remove it and it will be passed on through generations. So, having one copy of that allele is advantageous but not deleterious.
Gene flow
With humans migrating throughout the different parts of the world, sickle cell allele is passed from one person to another or in different populations. It is actually advantageous to have one copy of this allele especially if there’s malaria in the area, which the allele is resistant.
Answer: try d
I think it’s d because ecological succession
Is the process in which an environment changes or develops overtime
Answer: Either the cell wall or the membrane
Explanation:
The cell wall proctects the cell while the membrane forms structures inside of the cell
