Carbohydrates

Question 1

Define photosynthesis

Answer 1

Photosynthesis is the process by which green plants use sunlight to make sugar( glucose) from carbon dioxide and water

Question 2

Explain the process of photosynthesis

Answer 2

Plant roots absorb water( H²0) from the soil. Leaves take in carbon dioxide ( CO²) from the air. Chlorophyll in leaves absorbs energy from the sun.
Thus Results in the production of glucose( sugar) ( C⁶H¹²O⁶) and then oxygen ( O²) is released into the air

Question 3

List the 3 elements found in carbohydrates

Answer 3

Carbon(C) ,hydrogen (H) and oxygen( O).

Question 4

Classify carbohydrates and give 3 examples and 3 sources of each

Answer 4

Monosaccharides:
A simple sugar that contains one single sugar unit. It is the smallest unit of a carbohydrate.
E.g + source
Glucose- Fruit
Fructose- Fruit and honey
Galactose- digested milk

Disaccharides:
Formed when two monosaccharides join, resulting in the loss of a water (H₂O) molecule (condensation reaction)

E.g + source
Maltose( glucose + glucose) - barley
Sucrose (glucose + fructose)- Table sugar
Lactose (glucose + galactose)- Milk

Polysaccharides:
Formed when three or more
monosaccharides join together, resulting in the loss of a water (H₂O) molecule with each new link (condensation reaction). Chains can be straight or branched.

E.g + Sources
Starch-Cereals ond potatoes
Pectin-Fruit and nuts
Glycogen- meat
Gums- plants and seaweed
Cellulose ( dietary fibre)- skins of fruit and vegetables

Question 5

Classify carbohydrates with reference to the chemical formula

Answer 5

Monosaccharides: C⁶H¹²O⁶
Disaccharides: C¹²H²²O¹¹
Polysaccharides: (C⁶H¹⁰O⁵) n
( n refers to the number of Monosaccharides joined together)