a cell structure and funtioning in human body

The cells that make up our body are so small that you would fit over 200 of them on the full stop at the end of this sentenc..

Did You Know? - The cells that make up our body are so small that you would fit over 200 of them on the full stop at the end of this sentence. The word cell is derived from the Latin word cellula which means a little room. It was the British botanist Robert Hooke who, ..

Respiratory System in Human Beings The respiratory system starts with the nose that encloses the nasal cavity. The nasal cavity opens to the outside through the openings called the nostrils. The nasal cavity is divided into two portions by a cartilagenous septum and is lined by fine ..

The human heart is a muscular, cone-shaped, hollow organ about the size of a fist (about 12cm in length and 9cm in breadth). The heart is situated behind the sternum, between the lungs in the thoracic cavity. The heart is tilted slightly such that its apex is towards the left side. T..

Human Reproductive System - In human beings, sexual reproduction takes place. Sexes are separate and hence they are known to exhibit sexual dimporphism. Males have sex organs called the tetes while the females have sex organs called the ovaries. Even in the external appearance, ..

Summary - 1) The human body has elaborate mechanisms for protection against foreign bodies, germs and cancer cells. 2) Immunity is either innate or acquired. 3) Innate or non-specific immunity refers to a wide variety of body responses against a wid..

Circulatory System - The transport system in animals is called the circulatory system. The materials are transported from one part of the body to another by a mass flow system which is the circulatory system. The animals, particularly the more advanced forms, have a higher metabolic rate...

The closed circulatory system can be represented as follows. Diagram showing inter-relationship between artery, vein and capillary The closed blood vascular system is a very well developed system This is so because, a) The organisms have a thick body wall to prevent the evaporation of wat..

Why are Organisms Composed of Cells? - All living organisms are composed of structural and functional units called cells. The body of a living organism may be composed of a single cell - as in unicellular organisms or many cells - as in mu..

Each ovule is attached to the placenta by a stalk called funicle. The body of the ovule fuses with the funicle to form the hilum in the seed. The ovule consists of one or two integuments, accordingly the ovules are called unitegmic or bitegmic respectively. The integuments leave a small ..