PL HELP 1. The worst case of desertification occurs in the Sahel region. Why?

2. Most deforestation is caused by...?

3.What three major rivers in Africa are used as transportation routes for those that need to go from the interior Africa to the coast?

4. The primary cause of water pollution in Africa is natural phenomena. What are some of these natural phenomena?

Please help I will mark

3.

Explanation

What three major rivers in Africa are used as transportation routes for those that need to go from the interior Africa to the coast?

the answer is "meiosis ii in the mother".

the procedure of meiosis includes two divisions of the hereditary material. the main division is known as the decrease division – or meiosis i – on the grounds that it lessens the quantity of chromosomes from 46 chromosomes or 2n to 23 chromosomes or (n depicts a solitary chromosome set). in people, the decrease division results in two sperm cells each with 23 chromosomes or an egg cell with 23 chromosomes and one disposed of polar body. the second division – or meiosis ii – is called equational division. the two sperm cells split again creating four sperm cells, each with 23 or n chromosomes. in oogenesis, the egg cell and polar body partition to shape the ovum and two extra polar bodies. along these lines, the posterity are guaranteed to get one portion of the chromosomes from the mother and one half from the dad.