STPM Biology - chapter 1: Reision essay question 19

19. Protein is very important for living organism. Give four types of proteins and their functions.[4]


Answer:

Types of proteins and their function
-Catalytic/ enzymatic

  ~To catalyse biological reactions
-Transport

  ~To transport oxygen and carbon dioxide in blood circulation (haemoglobin)
  ~To transport other substances to other part of the cells or within cells
-Regulatory/ messenger/ hormone

  ~Coordination of cellular activities through messenger molecules (insulin)

-Storage for molecules required by the organism
 ~(ovalbumin - storage for amino acid; calmodulin - storage for calcium; ferritin - storage for iron)
-Structural support for organism (cocoon, hair, skin, keratin)
-Immuno/ defence

  ~Protection against diseases (antibodies)
-Receptor Response of cell to chemical stimuli
-Contractile and motor

  ~For movement and mobility (actin and myosin)
-Toxins Act as hydrolytic enzymes
-Visual protein

  ~For vision

Assignment submitted by H. L., Lim, H.P., Tan, S. Y., Tan, H.S., Teow, A.M., Chia 2011/2012 (IBM)