2. Structure and function in living organisms - (i) excretion

Question 1

What does metabolism mean?

Answer 1

Metabolism is the term used for all the chemical reactions that go on inside an organism’s body. These reactions build up molecules, and break them down. They are controlled by enzymes.

Question 2

What Metabolic reactions occurs in plants?

Answer 2

1. Aerobic respiration: Breakdown of Glucose in the presence of Oxygen to produce Carbon Dioxide and Water to release energy; occurs in the Mitochondria of the cell
   As a waste product of Aerobic Respiration, Carbon Dioxide will diffuse out of the Stomata via diffusion
2. Photosynthesis: Production of Carbon compounds (Glucose) in cells by using Carbon Dioxide, Water, and light energy from the Sun
   As a waste product of Photosynthesis, Oxygen will diffuse out of the Stomata via diffusion

Question 2

What does excretion mean?

Answer 2

Removal of waste products of metabolism from the body

Question 3

Explain what waste products the lungs excrete?

Answer 3

Carbon Dioxide, Lung excretes Carbon Dioxide as a waste product of Aerobic respiration via Exhalation.

Question 4

Explain what waste products the kidney excrete?

Answer 4

Excess Water, Salts and Urea, Kidney excretes excess Water, Salts and urea by producing Urine via osmoregulation

Question 5

Explain what waste products the skin excretes?

Answer 5

Excess Water and Salts, Skin excretes excess Water and Salts through sweat glands of skin by producing sweat