Plants and animals need elements, such as nitrogen, phosphorus, potassium, and magnesium for proper growth and developme..
Upon fertilization, a zygote forms and develops into an embryo. This tutorial elaborates on the growth and development f..
The human respiratory system is an efficient system of inspiring and expiring respiratory gases. This tutorial provides ..
This tutorial recognizes the importance of food as a source of energy that will fuel many biological processes. A good d..
Autotrophs flourished, absorbing carbon and light. Soon after, primitive life forms that could assimilate oxygen thrived..
Freshwater ecosystem is comprised of four major constituents, namely elements and compounds, plants, consumers, and deco..