DNA and RNA each contain four nitrogenous bases. They have 5 not 4.
Answer:
directional selection
Explanation:
Directional selection is the most common type of natural selection and occurs when some individuals with characteristics favorable to the conditions of the environment in which they live, have survival advantages over individuals who do not have this advantage, who end up dying.
Imagine, for example, a graph showing the directional selection in the same species of moths. Moths of the same species have white and brown collations, in summer, brown moths can camouflage themselves on tree trunks, while white moths cannot and are easily captured by their predators, which means that the amount of white moths decrease. In this graph, the population of white moths would be at a minimum, at the same time that the population of brown moths would be at maximum.
However, with the arrival of the reverse, snow begins to cover the trees, allowing white moths to camouflage themselves more easily. The brown moths, then, are very exposed to predators, causing their population to reach the minimum while the population of white moths reaches the maximum.
Answer:
Choice B
Explanation:
"Permeable" means "Letting solids or liquids through (a material.)" "Semi" means "half or partly." So "semipermeable" means allowing some objects through, but not all.
Other molecules such as proteins, starch and sugar are simply too large to diffuse across the membrane. Sometimes, some of these large molecules are transported across the cell membranes by carrier proteins; this does not require energy and as a result is a form of passive transpor
Answer:
HIV/AIDS
HIV is a disease in the blood
nothing else
it is majorly caused through unprotected sex
there are other factors tho.
But it can be transmitted in blood transfusion
it is in the blood cells
