Cell and Structure

Did you know that cells have different features which help them to perform their functions? In the previous lesson we learnt about the parts of the cell and it's structure. ( click here to check out the previous lesson ) In this lesson we will discuss the modification of cell structure for specific functions.

Modification of Cell Structure:-

Growth in an organism involves cell division. New cells produced may change and develop into new issues. This process of change is called differentiation. There are many types of cells in organisms. They differ in size and shape and are adapted to perform specific functions.

The following table gives a few examples of cells with different structures, explaining how these specific structures of these cells help in their functioning within the organism.

Cell Structure	Adaptation To Function
	Being long and narrow, the root hair increases the surface area to volume ratio of the cell for efficient absorption of water and mineral salts from the soil.
	The red blood cell contains a red pigment called haemoglobin, enabling the cell to transport oxygen from the lungs to all parts of the body. Its circular, biconcave shape (thin from center) increases surface to volume ratio. As a result, oxygen can diffuse into and out of the whole cell at a faster rate.
	Xylem vessels transport water and mineral salts from roots to the stem and leaves. There are no cross-walls and no protoplasm present which helps water to move easily through the lumen ( hollow space in the vessel ). Lignin strengths the walls and prevents collapsing of the vessel. When several xylem vessels are bundled together, they provide mechanical support to the plant.

Tissues, Organs and Systems:-

Organisms are made of around 60,000 billion cells. Organisms have tissues, which are a group of similar cells performing a specific function, examples of such tissue is epithelial tissue. Different types of tissues then make up an organ. Different organs then make up an organ system. Different organ system then make up the organism.

Example:-

Cells ------ Tissue ------ Organ ------ Organ System ------- Organism

Muscle cells ------ Muscle tissue ------- Stomach --------- Digestive System ------- Organism

Now, muscle tissue is not the only tissue that make up the organ stomach. There are other tissues also, like connective tissues. Also the stomach is not the only organ in the digestive system, other organs like small intestine and liver are also present. With the digestive system there are other systems, like circulatory system, that make up an organism.

*All pictures are taken from the google*