Levels of Organisation

Topic Content:

There are different levels of organisation of life e.g. cells, tissues, organs and systems.

1. Cells:

The cell is the basic unit of a living thing capable of doing all life activities.

A cell can exist independently as a single-celled or unicellular organism or as a part of a multicellular organism.

Examples of unicellular organisms are:

a. Amoeba
b. Paramecium
c. Euglena
d. Plasmodium
e. Trypanosome
f. Chlamydomonas

Examples of multicellular organisms are:

a. Blood cells
b. PhloemPhloem is a plant vascular tissue that conducts foods made in the leaves during photosynthesis, downwards to all other parts of the plant. More cells
c. Spermatozoa
d. Ova or eggs
e. Nerve cells
f. Epidermal cells

2. Tissues:

A tissue is a collection of cells which are similar in structure and perform the same function. Hydra and obelia are organisms at the tissue level.

Examples of tissues in higher plant organisms are:

a. XylemXylem is a plant vascular tissue that transports water and dissolved minerals from the roots to the stems and leaves and also provides physical support. Xylem is one of the two... More
b. Phloem
c. Epidermal
d. Sclerenchyma tissues

Examples of tissues in