A transport system refers to a group of organs or channels through which materials are carried, usually dissolved in liquid forms, from one part of the body to another.
NEED FOR TRANSPORT SYSTEM
The primary purpose of the transport system is to move materials throughout the body of the organism.
In simple or unicellular organisms, such as protozoa more diffusion is sufficient to move materials in about and out of the cell because;
i) The body is small in size.
ii) It has large surface area to volume ratio.
iii) Materials have to move over short distances.
However, for large organisms such as a human beings with small surface area to volume ratio, diffusion is supplemented by well co-ordinated mass flow systems to transport materials across greater distance round the body.
MEDIA IN TRANSPORTATION
i) Protoplasm in unicellular organisms
ii) Body fluids in vertebrates
iii) Blood in multicellular animals
iv) Lymph in vertebrates
v) Cell sap/latex in higher plant
MATERIAL TRANSPORTATION IN PLANTS
ii) Mineral salt
iii) Manufactures food
iv) Excretory products
vi) Carbon dioxide
MECHANISM OF TRANSPORTATION IN PLANTS
i) Cytoplasmic streaming / cyclosis
ii) Conducting through the xylem tissues
iii) Transportation through the phloem tissues
iv) Transportation through the stomata and lenticels.
MATERIAL TRANSPORTATION IN ANIMALS
i) Excretory product (urea, carbon dioxide, water)
ii) Products of digestion/food materials(glucose, amino acid, vitamins)
MECHANISM OF TRANSPORTATION
i) Protoplasmic streaming
ii) Open transport system
iii) Closed transport system