cells organisation

Organization of Cells and Formation of an Organism.

Levels of organization

Cells→Tissues→Sysetm→Organisms

A tissue is a group of cells performing the same function.

 

Examples of tissues in plants

Tissue Function
Photosynthetic Manufactures food for the plant
Xylem Transport of water and mineral salts from the roots to the leaves
Phloem Transports food and substances from the leaves and storage organs to other parts of the plant
Epidermal Covers and protects the plants

Prevents excessive water loss

 

Examples of tissues in animals

Tissue Function
Blood Transports materials from one part of the body to another

Protects the body against infection

Nerve Transmits nerve impulses
Muscle Produce movement through contraction and relaxation of cells
Skeletal Provides support

Provides movement

 

Organs and systems

Organs

An organ is a collection of tissues specialized in carrying out a specific function.

Examples in plants include: leaves, stems, roots and flowers.

Examples in animals include; heart, brain stomach, liver kidney, limbs etc

System

A system is a collection of different organs performing a specific function.

Examples in plants include; roots and shoot system.

Examples in animals include; Digestive, circulatory, excretory, nervous, skeletal etc

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