Why does meiosis produce cells with half the chromosomes

Find and describe the climate zone in which you live,where else in the world do you find this climate zone? do you have any ideas about why the climates might be similar?

The oxidizing agent our bodies use to obtain energy from food is oxygen (from the air). if you breathe 15 times a minute (at rest), taking in and exhaling 0.5 l of air with each breath, what volume of air do you breathe each day? air is 21% oxygen by volume. what volume of oxygen do you breathe each day?

Why do carbohydrate molecules function so well as fuel for the body?