Organisms employ different strategies to boost its defenses against antigens. Humans have an immune system to combat pat..
This tutorial elaborates on how the nervous system works, particularly at the tissue level of the brain. There are three..
Plants are characterized by having alternation of generations in their life cycles. This tutorial is a review of plant m..
Hormones are essential in the regulation of the activity of the various biological systems of the human body. The ineffi..
Mammals are a diverse group of organisms, where most of them develop their offspring within the uterus of the mother. Ov..
This tutorial looks at the relationship between organisms. It also explores how energy is passed on in the food chain an..
