Cell structure and

micro-organisms

Animals, Plants and micro-organisms, all are living things.

In all living organisms we observe circulation, growth,

respiration, excretion, reproduction, etc life cycle processess.

,..

Circulation, growth, excretion, reproduction

In all living things different body systems and organs bring about these processes.

In living things bodies are made up of cells.

In 1665,Robert Hooke was the first one to find that the structure of cell resembles that of a

honeycomb, made up of many small compartments. This was a thin section of cork,

he observed under a microscope.

There are certain differences and certain similarities

between the plant cell and the animal cell.

Cell is made of various constituents called organelles..

Animal cell – cell Membrane, cytoplasm, nucleus,

Golgi body, mitochondrion, Vacuole.

Plant Cell organelles - cell membrane, cell wall, cytoplasm ,ribosome,plastids ,Nucleus, vacuole.

Organelles Structure FunctionCell membrane Outer covering,

thin, flexible layer•Protects the inner parts of cell •Regulates the flow of substances that enter into and pass out of the cell•Maintains the shape of the cell

Organelles Structure Function

Cell Wall Made up of cellulose

•Gives the cell strength•Protection of inner components

Organelles Structure Function

Nucleus Round

(Mostly)

Chromosomes made from DNA are inside the nucleus

•Controls all the functions of the cell•Takes part in cell division

Organelles Structure Function

Cytoplasm Semi-fluid To accommodate various organelles and control their movements.

Organelles Structure Function

Mitochondria Tabular shape, double wall, inner wall has folds

•Produce energy from the food material in the cell

•Powerhouse of the cell

Organelles Structure Function

Golgi Bodies Stacks of flat, membrane-bound sacs

Store enzymes

Organelles Structure Function

Vacuole Empty space Stores products of excretion and secretions

Animal cells Plant cells

There is no covering around the cell membrane

The cell wall surrounds the cell membrane

Vacuoles are small [Vacuoles are large

No chlorophyll Has chlorophyll

Large animals, plants are made up of many cells whereas some micro-organisms are uni-cellular.

e.g. Virus, bacteria, algae,etc.

Some micro-organisms are useful while some are harmful.

Virus: Simple structure, Has a covering of protein. DNA and RNA causes various diseases in plants and animals.