Science

This awe-inspiring video shows of the process of human reproduction from conception to birth. It explains how mitosis and meiosis create genetic variation, how the ovum travels from the ovary to the uterus, how sperm pass the cervix, how one sperm achieves fertilization with the ovum, how the zygote begins cell differentiation, and how the embryo grows into a fetus ready for birth.

Any ecosystem needs energy to sustain it, and the organisms within it. This energy comes in massive quantities from the Sun, although only a tiny fraction of the solar energy hitting the Earth goes towards sustaining life. The flow of energy through an ecosystem is complex, and vital to sustaining all life within it.

An introduction to stem cells while assuming no prior knowledge, and covers the following topics: what stem cells are, the difference between embryonic and adult stem cells, IVF as a key source of embryonic stem cells, therapeutic cloning (somatic cell nuclear transfer), the difference between therapeutic and reproductive cloning, potential medical applications of stem cell research and a brief

Our appetite for the earth's resources and consumer goods has led to increased levels of carbon dioxide entering our atmosphere, trapping more heat from the sun and leading to global warming of the atmosphere.