Passive Transport

Passive Transport

Plasma membranes must allow certain substances to enter and leave a cell, and prevent some harmful materials from entering and some essential materials from leaving. In other words, plasma membranes are selectively permeable—they allow some substances to pass through, but not … Read more

Membrane Proteins

Membrane Proteins

Biological membranes consist of a continuous double layer of lipid molecules in which membrane proteins are embedded. Although the lipid bilayer provides the basic structure of biological membranes, the membrane proteins perform most of the membrane’s specific tasks and therefore … Read more

Nucleus- Definition, Structure, Functions and Diagram

Nucleus- Structure and Functions

Nucleus Definition The cell nucleus​ is a membrane-bound structure that contains the cell’s hereditary information and controls the cell’s growth and reproduction. It is the command center of a eukaryotic cell and is commonly the most prominent organelle in a cell accounting for about … Read more

Lysosomes- Definition, Structure, Functions and Diagram

Lysosomes- Structure, Enzymes, Types, Functions

Lysosomes Definition Lysosomes are membrane-bound, dense granular structures containing hydrolytic enzymes responsible mainly for intracellular and extracellular digestion. The word “lysosome” is made up of two words “lysis” meaning breakdown and “soma” meaning body. It is an important cell organelle … Read more

Embryo Transfer

Embryo transfer

Embryo refers to the early developmental stage of an animal while it is in the egg or within the uterus of the mother. In humans the term is applied to the unborn child until the end of the seventh week following conception; … Read more

Membrane Lipids

Membrane Lipids

Biological membranes consist of a lipid bilayer to which proteins and carbohydrates may be associated or covalently linked. Membrane lipids are lipids involved in forming the structure of biological membranes – both the cell membrane and intracellular membranes – and … Read more