Question

A. What is meant by diffusion? Give one example of diffusion in gases.
B. Why do gases diffuse very fast?
C. Name two gases of air which dissolve in water by diffusion. What is the importance of this process in nature?

Answer 1

The cell membrane is permeable only to certain molecules. It allows some substances to flow through quickly and others to pass through slowly, while it prohibits others from passing through at all.
Some tiny molecules, such as water, oxygen, and carbon dioxide, can pass right through the cell membrane's phospholipids. Larger molecules, such as glucose, necessitate the use of a specialised transport protein to help them traverse the cell membrane.
Proteins and other large molecules are too massive to pass through the cell membrane, which is said to be impermeable to them.

Complete answer:
Part A: Diffusion is the movement of molecules in the presence of a concentration gradient. It is a vital process that occurs in all living things. Diffusion is a process that aids in the movement of molecules into and out of cells. The molecules move from a high-concentration zone to a low-concentration zone until the concentration is uniform across the board.
Diffusion is demonstrated by the way the scent of a perfume spreads around a space.
Part B: Because the particles' kinetic energy is so high in the vapour state, they easily combine with the particles of Air. When compared to solids and liquids, the intermolecular space of gases is quite large. As a result of this, gas molecules travel at a faster pace, resulting in a faster diffusion rate.
Part C: The two gases in air that dissolve in water by diffusion are carbon dioxide and oxygen. For photosynthesis, carbon dioxide is essential for aquatic plants. Aquatic animals rely on oxygen to breathe.

Note:
Plant transportation is an important and natural phenomenon that occurs in all higher plants. For the efficient functioning of cells and tissues, all plants require some necessary organic and inorganic material. Three modes of transportation are used in this process.
1. Diffusion
2. Facilitated Diffusion
3. Active Transport
Types of diffusion in plants-
1. Simple diffusion- The diffusing molecules do not mix with the membrane's contents.
2. Facilitated diffusion- Transporter proteins help the chemicals diffuse through the membrane.