Digestive, Circulatory And Repitory Systems

Question 1

What is meant by digestion and how is it a chemical and physical process?

Answer 1

• The physical and chemical breakdown of food into soluble particles to pass into body cells
• Chemical digestion: break down food by enzymes and acid in stomach
• Physical digestion: muscle action and teeth

Question 2

Function of small intestine, large intestine and anus?

Answer 2

• Small intestine absorbs food into blood stream
• Large intestine passes undigested food through before being egested
• Solid waste disposes through the anus

Question 3

What is an enzyme and what enzymes work in the mouth and stomach?

Answer 3

• An enzyme is a catalyst produced by living cells that speeds up chemical reactions without changing itself
• Mouth: Salivary amylase breaks to starch into a sugar (maltose.) pH 8-9
• Stomach: Pepsin digests protein with hydrochloric acid. pH 1-2

Question 4

What is mitochondria and the word and chemical equation?

Answer 4

Mitochondria are tiny organelles in the cytoplasm
Word equation: glucose+oxygen -> carbon dioxide+water+energy
Chemical equation: C6H1206 + 6O2 -> 6H2O + energy

Question 5

What is aerobic respiration?

Answer 5

Involves oxygen - releasing energy from food when oxygen is present
Glucose+oxygen -> carbon dioxide + water + energy

Question 6

What is anaerobic respiration?

Answer 6

Does not involve oxygen->releasing oxygen from food when oxegen is not present

Glucose->lactic acid+small amounts of energy (muscle cramps after exercise->lack of oxygen)
OR
glucose->alcohol+carbon dioxide+small amounts of energy

Question 7

What is fermentation?

Answer 7

Used in baking industries/ brewing when yeast is used
Eg. Baking - dough rises
Brewing- beers and wine

Question 8

How the circulatory and digestive systems interact?

Answer 8

• Food is absorbed into the blood through villi in the small intestine and is carried in the blood to the liver
• Transports digested food around the body

Question 9

How does the circulatory system and respiratory system interact?

Answer 9

• Transports gases around body

- Oxygen diffuses from alveoli into the blood and is combined with hemoglobin and is carried to all body cells

Question 10

How does the digestive and respiratory systems interact?

Answer 10

• The glucose broken down by the digestive system is used for respiration in the mitochondria
• Body needs energy from respiration to digest food