Core tips

• Robert Hooke in 1665 first discovered the cell.
• Study of cells is called Cytology or Cell Biology
• Cells are structural and functional units of life.
• Most cells are microscopic.
• Electron microscope is used to magnify very small objects up to 2 billion times.
• Cells are made up of membranous structures called cell organelles.
• Cell membrane, cell wall, Golgi bodies, ribosomes, Mitochondria, lysosomes, nucleus and vacuoles are the organelles.
• Each cell organelle has certain specific functions.
• There are certain important differences between plant and animal cells.
• Certain very microscopic organisms exist. These are called as microorganisms.
• Viruses can be studied only under electron microscope.
• Bacteria are microscopic. They are important in their role. Some of these are beneficial while some are very harmful. 
• Fungi live on dead and decomposing materials. Some of them are found on the body of humans.
• Penicillium an antibiotic was first prepared from the fungus.
• Yeast cells are useful in fermentation industry.
• Protozoa are yet another kind of micro- organisms.
• Algae are found in wet and damp conditions. These are green in color.