Body Chemistry

Question 1

Structure and function of carbohydrates

Answer 1

• S = made of sugars, comprised of the elements carbon, hydrogen and oxygen
• F = primary energy source as well as energy storage as glycogen in liver and muscles

Question 2

Structure and function of proteins

Answer 2

• S = made of different combos and folding of the 20 amino acids (AAs) - essential (need in diet b/c not produced in body) and non-essential (don’t need in diet b/c produced in body)
• F = repair and maintenance, hormones, antibodies, 3rd source of energy, enzymes

Question 3

Structure and function of enzymes

Answer 3

• S = protein that has an active site which is specific and complementary to a substrate for its role
• F = biological catalyst that speeds up the rate of a chemical reaction by lowering the activation energy (otherwise metabolic processes will occur too slowly to sustain life)

Question 4

Structure and function of lipids

Answer 4

• S = hydrophobic, waxy/fatty/oily substances
• F = insulation for thermoregulation, protection of organs, secondary energy source

Question 5

Structure and function of water

Answer 5

• S = polar substance, colourless liquid at room temp
• F = transport blood & nutrients, lubrication of joints and cavities, sweating for thermoregulation, removal of waste through urine and faeces

Question 6

Metabolism

Answer 6

Sum total of all chemical reactions occuring in an organism

Question 7

Identify and outline the 2 types of metabolism

Answer 7

• Anabolic: building up larger substances, usually requires energy
• Catabolic: breaking down substances to gain energy

Question 8

Worded equation for aerobic cellular respiration

Answer 8

6 glucose + 6 oxygen -> 6 carbon dioxide + 6 water + 30-32 ATP

Question 9

Homeostasis

Answer 9

The condition of maintaining a relatively stable internal environment, within narrow limits, in the face of external change

Question 10

Receptor

Answer 10

• detects changes within the body

Question 11

Control centre/coordinator

Answer 11

• Processes information from the receptor and works to initiate a response
• Usually a part of the brain e.g. hypothalamus

Question 12

Effector

Answer 12

A body part which takes action to respond to the stimulus

Question 13

Response

Answer 13

• Outcome of the feedback loop
• e.g. if blood pressure is high, the response would be that the blood pressure decreases back to within normal limits

Question 14

Negative feedback loop + e.g.

Answer 14

• Stimulus > receptor detects stimulus > control centre initiates effector > effector initiates response > response opposes stimulus back to WNL
• e.g. body temperature, blood pH, blood glucose

Question 15

Positive feedback loop + e.g.

Answer 15

• Stimulus > receptor detects stimulus > control centre initiates effector > effector initiates response > response amplifies stimulus
• e.g. dilation of cervix during childbirth