Human Health And Systems

Question 1

Stages of nutrition.

Answer 1

Ingestion/Eating: Food is taken in by the body.
Digestion: Food is broken down.
Absorption: Digested food passes into the bloodstream.
Assimilation: using the food in the cells of the body
Elimination: Getting rid of undigested food.

Question 2

Chemical digestion

Answer 2

Involves the use of
chemicals called
enzymes to break
down food
◼ Enzymes are
chemicals that
speed up reactions
without being used
up in the reaction
◼ Enzymes act on a
substrate and
breaks it down into a
product
◼ Example: substrate
= starch, enzyme =
amylase (saliva),
product = maltose
(sugar)

Question 3

PLASMA

Answer 3

• Liquid part of the blood
• Pale yellow - mostly water
• Function: to transport chemicals and heat
- Chemicals (Useful): Food, Hormones
- Chemicals (Waste): CO, Salts, Urea
- Heat: Generated from chemical reactions, transported around to maintain 37°C
• Also carries the red blood cells, white blood cells, and platelets.