1. What is diffusion? 2. Explain how the following factors affect the rate of diffusion: (a) Temperature (b) Size of the particles (c) Concentration gradient 3. State the importance of diffusion to living organisms.
Answer (1)
What is diffusion?
Diffusion is the process where molecules move from an area of higher concentration to an area of lower concentration until they are evenly distributed. This process occurs because molecules are constantly moving and colliding with each other, causing them to spread out. It is a passive process, meaning it does not require energy.
Explain how the following factors affect the rate of diffusion:
(a) Temperature:
Higher temperatures increase the kinetic energy of molecules, causing them to move faster. As a result, diffusion occurs more quickly at higher temperatures because molecules collide and spread out more rapidly.
(b) Size of the particles:
Smaller particles diffuse faster than larger particles. This is because smaller molecules move more easily between the spaces in a solvent or across a membrane, allowing them to spread out more quickly.
(c) Concentration gradient:
The concentration gradient refers to the difference in concentration between two areas. A larger concentration difference will lead to a faster rate of diffusion because there is a greater incentive for molecules to move from the area of higher concentration to the area of lower concentration.
State the importance of diffusion to living organisms.
Diffusion is crucial for living organisms as it is involved in several essential biological processes:
Gas Exchange: In the lungs, oxygen diffuses from the alveoli into the blood, and carbon dioxide diffuses from the blood into the alveoli to be exhaled.
Nutrient Absorption: In the intestines, nutrients such as glucose and amino acids diffuse into the blood from the digestive tract.
Waste Removal: Waste products like carbon dioxide and urea diffuse out of cells into the blood to be excreted.
Diffusion helps maintain homeostasis by allowing cells to receive necessary substances and remove wastes efficiently.
