4.4 Lipids

Lipids are complex organic compounds that made up of carbon, hydrogen and oxygen. Some lipids contain the elements nitrogen and phosphorus.The ratio of hydrogen atoms to oxygen atoms in a lipid molecule is higher than the    2 : 1 ratio in carbohydrates.Lipids are insoluble in water. However, they are soluble in other lipids and … Read more

4.3 Protein

Proteins are complex compounds that made up of carbon, hydrogen and nitrogen. Some proteins contain sulphur and phosphorus.It is needed by the body for growth, repair of damaged tissues and synthesis of secretions (enzymes, mucus, hormones.)Proteins are polymer that made up of monomers called amino acids. Each molecule of amino acid has one amino group (-NH2) and one carboxyl group ( -COOH).Two molecules … Read more

4.2.3 Polysaccharides

Polysaccharides are formed when more than two monosaccharides (usually more than hendreds) combine through condensation. Some characteristics of polysacharides are: do not dissolve in water do not taste sweet do not crystallisePolysaccharides can be hydrolysed by adding acid, boiling and action of enzymes. Examples of polysaccharides Starch storage of carbohydrate in plants. The iodine test is used for confirming the presence … Read more

SPM Form 5 Biology – Exercises

01 Transport The Circulatory System (7 Questions) The Mechanism of Blood Clotting (3 Questions) The Lymphatic System (4 Questions) The Role of Circulatory System in Body Defense Mechanism (4 Questions) 02 Support and Locomotion Support and Locomotion in Humans and Animals 1 (6 Questions) Support and Locomotion in Humans and Animals 2 (6 Questions) Support System in Plants (4 Questions) 03 Coordination and Response The Role of … Read more

SPM Form 4 Biology – Exercise

01 Cell Structure Cell Structure and Function 1 (6 Questions) Cell Structure and Function 2 (5 Questions) Cell Organisation 1 (5 Questions) Cell Organisation 2 (5 Questions) Cell Organisation 3 (3 Questions) 02 Movement across Plasma Membrane Movement of Substances Across the Plasma Membrane 1 (5 Questions) Movement of Substances Across the Plasma Membrane 2 (5 Questions) Movement of Substances Across the Plasma Membrane … Read more