Digestion and absorption are important physiological processes through which the food we eat is broken down into simpler substances and then taken into the bloodstream for use by the body. 1. Digestion Digestion is the mechanical and chemical breakdown of complex food substances into simpler, smaller molecules that can be absorbed by the body. The…
1. Introduction The cell is the basic structural and functional unit of life. All living organisms are made up of one or more cells. Cells carry out essential life processes such as nutrition, respiration, growth, reproduction, excretion, and response to stimuli. The study of cells is called cell biology or cytology. Cells differ greatly in…
Introduction The Earth contains an enormous variety of living organisms. They differ in their size, shape, structure, habitat, mode of nutrition, reproduction, life cycle, and other characteristics. This variety of life is known as biological diversity or biodiversity. From microscopic organisms such as bacteria to large organisms such as elephants and trees, every organism has…