Answer:Determinants
Explanation:
Determinant covers causes, risk factors, mode of transmission (why and how)
Rough Endoplasmic Reticulum. it has a rough surface and is covered in ribosomes.
Answer:
Oil shale is a form of sedimentary rock that contains kerogen, which is released as a petroleum-like liquid when the rock is heated. Tar sands are a combination of clay, sand, water and bitumen, which is a heavy hydrocarbon.
Additional info:
The term oil sands refers to a particular type of nonconventional oil deposit that is found throughout the world. Oil sands, sometimes referred to as tar sands, is a mixture of sand, clay, other minerals, water, and bitumen. The bitumen is a form of crude oil that can be separated out from the mixture.
The primary distinction between crude or conventional oil and shale oil is the way it collects. The oil in shale is typically found in smaller batches. As a result, shale oil often needs to be fractured so that the oil trapped within the shale can be recovered.
Answer:
here.
Explanation:
Due to the prevalence of malaria in Africa, the allele for sickle cell anemia (HbS) provides a selective advantage. That's why it remains in the population.
A normal African person (HbAHbA), with normal haemoglobin, will not die of anemia, but will die of malaria.
An African person with sickle cell anemia (HbSHbS), with abnormal haemoglobin, will die of anemia.
A heterozygous African person (HbAHbS), with half of his red blood cells (RBCs) being normal and the other half being sickle-shaped, will neither die from anemia, nor malaria since the plasmodium will be incapable of completing its life cycle in the abnormal RBCs.
Thus heterozygous African people will grow, reproduce and pass on the HbS allele to the next generations.