Answer:
HIV destroys helper T cells
Explanation:
The evading viruses destroys helper T cells or the CD4+ thus the body can no longer stop some infections. The secondary infections also called opportunistic infections are rampant with people who have AIDS. This is because helper T cells help fight against most infections in the body.
The first one, ii. Natural selection and the formation of inseticide resistant insects or antibiotic resistant bacteria.
This can be explained in very simple way. As we all know, natural selection works in a way that only that adapted living beings are going to survive through a specific environment, whether it's because they can grab their food without too much work, or even that they can adapt to the weather. When we use inseticide, we are killing lots of non-resistant insects, and what's left are those that are resistant to this inseticide, and they'll reproduce again, and again we'll go through the same process, but remember, this insect is now stronger and more resistant that before.
The second case, iii. speciation and isolation give three examples how it may occur.
Well. the allopatric speciation and isolation will happen when theres a geographic barrier between one species. This one then is divided into two diffent habitats, but what can divide than could be a mountain, a tree, a river, a rock, anything. And this could be too called as a geographic isolation, because in this new environment, species are going to develop in a different way.
Answer:
Oxygen is needed to break the sugar into carbon dioxide, releasing energy the plants can use to stay alive. However, plants also take in energy from the sun(light), carbon dioxide from the atmosphere, and water from the soil; they use all of them in order to make sugar, and release oxygen.
Explanation: