IGCSE Science/Section 2: Structures and functions in living organisms/Cell structure

Cell organelles: Small structure having definite shape and performing specific functions

The organelles of an animal cell

The organelles of a plant cell

They are embedded in the cytoplasm, These structures are called cell organelles. Most cells have these organelles:

Name	Function
Nucleus	It regulates all important activities of the cell and plays an important part during cell division.
Cytoplasm	a place for chemical reactions to happen, and it contains enzymes which speed up these reactions
Cell membrane	It allows only certain substances to pass through small pores on it and protects the inner cell contents.
Mitochondria	It perform cellular respiration, referred as powerhouse of the cell.

Plants cells have:

Name	Function
Cellulose cell wall	It gives a definite shapes to the cell , allows all substances to pass through it and protect the inner cell contents called protoplasm.
Plastids	They are of 3 types: i)Chloroplast- It can trap solar energy and covert it into chemical energy in the form of food through the process of photosynthesis. ii)Chromoplast-It contains coloured(red, yellow, orange)pigments that impart colour to flowers and fruits. iii)Leucoplast-It is colourless pigment that store food in the form of starch, proteins and fats.
Vacuole	It stores sugar ,mineral and water in the form of cell sap and maintain the shape of cell.

Yeast cells have:

Name	Function
Chitin cell wall	to keep the structure of the cell
Vacuole	to store nutrients and food

Animal cells only have the basic organelles, but plants have all the basic organelles and some more: a cell wall, chloroplasts and a vacuole:

Diagram showing the parts of animal and plants cells. Plant-only organelles are shown in green.