Introduction to Biology

Greenhouse effect is the gradual warming of the air around the earth as a result of heat being trapped. Carbon-dioxide gas, methane, chlorofluorocarbons, etc are…

A cell may be defined by the following ways: (1) A cell is the structural and functional unit of life (2) The self-reproducing, structural and…

In animal cell there is a spherical body outside the nucleus, which is called centrosome. The fluid by which it is composed is called centrosphere.…

Golgi bodies may be flat, spherical or elongated. Normally they are present near the nucleus. It was first observed by a scientist named Golgi in…

Ribosomes are small spherical /granular organelle. They may occur freely in the cytoplasm and may be attached to the outer wall of the endoplasmic reticulum.…

In a mature cell a network is found in the cytoplasm. This is called endoplasmic reticulum. Endoplasmic reticulum is of two types – smooth and…

Krebs cycle, fatty acid cycle, electron transport system etc. take place in mitochondria (sing: mitochondrion). All energy producing process occurs in mitochondria for which mitochondria…

Chromoplast are variously coloured, other than green, mostly yellow and red in colour. They are also variable in shape. Chromoplast occurred in coloured part of…

Structurally cells are of various types. For that, in a certain cell, all the organelles or structural ingredients may not be present. For that reason,…

On the basis of Nuclear Structure Prokaryotic cell or Protocell: Nucleus is not well organized in these cells; nuclear membrane and nucleolus are absent here.…