Sickle cell anemia is persistent in the tropics because those with sickle cell anemia cant contract the malaria virus because of the shape of their blood cells, and this is advantageous in the tropics where there are more malaria cases. So those with sickle cell anemia live to pass on their genes.
Answer:
Microtubules have an inner diameter of 25 nm and an outer diameter of 30 nm.
Explanation:
Microtubules is a microscopic tubular structure that is present in the cytoplasm of cells; they are polymer structures that form part of the cytoskeleton that gives shape to cytoplasm of eukaryotic cells and some prokaryotic cells. A microtubules can be as long as 50 nm in diameter. The average inner diameter of microtubules is 25 nm while that of the outer diameter is 30 nm.
The bond between monomers of carbohydrates, e.g. glucose and fructose is a glycosidic bond-forming in this case a sucrose molecule (disaccharide). A glycosidic linkage is a C-O-C bond (ether). The underlying reaction is a condensation reaction where 1 OH- and 1 H+ are split off resulting in the formation of H2O.
Answer:
1: cell membrane
2. chloroplast
Explanation:
1. the cell membrane is the outer layer of an animal cell since they don't have cell walls
2. only plant cells have chloroplasts