2. Processes involved in transport of material across the cell, diffusion, active transport and osmosis.
3. Turgor and its importance in plants.
4. Transport of water and salts in plants.
5. Transpiration and factors affecting it.
6. Path of organic material in plants.
7. Open and closed circulatory system of animals and circulatory system of man.
The movement of substances from one part to another part within the body of an organism is called transport
Transport in unicellular organisms:
In simple and unicellular living organisms there is no need of any special transport system.The oxygen and dissolved substances from the outside enviroment can diffuse into the protoplasm directly.
living organisms Blood groups and Blood diseases.
In all living organisms’ plants and animals, physiological processes are continually taking place in their bodies. In order to sustain life, these processes must be kept going on for which the materials required, must be constantly transported to and from all parts of the body right down to the individual cells. Materials are also to be transported between the cell organism and external environment. In unicellular and simple multicultural organisms, the distribution of materials can be adequately brought about by diffusion and streaming movements of the cytoplasm (fig. 12.1).
Fig. 12.1 Streaming movement of cytoplasm (in Amoeba)
However, the evolution of more and more complex body structures recessitated the development of proper transport system, and more complex the organisms are, the more elaborate transport system they have. The complexity of transport system is related to the size and the metabolic rate of the living organism.
The materials to be transported are taken close to tissues be the transport system so that diffusion can occur efficiently into the cells. The primary function of the transport system is to maintain a link between all cells of the body and the external environment. It transports the nutrients to the points where they are to be used, facilitates the elimination of metabolic wastes of each cell and transports surplus substances to the specialized storage tissues or to out side their bodies.
Respiration In Living Organism Respiration is the process in which food is broken down into smaller particles along with the liberation of energy. The energy released is utilized for various metabolic activities. In this process oxygen is inhaled inside by a living organism when they breathe in and carbon dioxide is exhaled out.
Respiration process in humans:
In human beings, oxygen is inhaled inside the human body through nose or mouth. Oxygen is transferred to the entire body and enters the cell. Inside the cell food particles are broken down into smaller pieces in the presence of oxygen. During the breakdown of food particles, energy is released in the form of ATP. This energy released is utilized in certain metabolic activities.