7.1, 7.2, 7.3 diet, digestive system, physical digestion

Question 1

balanced diet

Answer 1

when body has the right amount of nutrients to function properly
e.g carb proteins fat vitamin minerals fibre water

Question 2

Carbohydrates

Answer 2

e.g: Bread, rice, pasta, potatoes, cereals, sugar.
use: Provide a main source of energy for the body.

Question 3

Fats and Oils

Answer 3

e.g: Butter, oil, nuts, cheese, fatty meat.
use: Provide a source of energy, insulation (keep the body warm), and help absorb fat-soluble vitamins.

Question 4

protein

Answer 4

eg: Meat, fish, eggs, beans, lentils, dairy products.
use: Needed for growth, repair of tissues, and making enzymes and other proteins.

Question 5

Vitamins

Answer 5

1. Vitamin C
   • e.g: Citrus fruits (like oranges), strawberries, green vegetables.
   • use: Needed for healthy skin, gums, and wound healing
2. Vitamin D
   • e.g: Fish liver oil, eggs, dairy products; also made in the skin in sunlight.
   • uses: Helps the body absorb calcium for strong bones and teeth.

Question 6

mineral ions

Answer 6

1) Calcium
• e.g: Milk, cheese, green leafy vegetables.
• uses: Needed for strong bones and teeth, and for muscle contraction.
2) Iron
• e.g: Red meat, liver, spinach.
• uses: Needed to make haemoglobin in red blood cells for transporting oxygen.

Question 7

Fibre (Roughage)

Answer 7

e.g: Wholegrain cereals, fruits, vegetables.
uses: Helps to prevent constipation by adding bulk to food and aiding movement through the digestive system

Question 8

Water

Answer 8

e.g: Drinks, fruits, vegetables, metabolic processes.
uses: Needed for transport, temperature regulation, and as a solvent for chemical reactions in cells.

Question 9

vitamin C deficiency

Answer 9

causes scurvy (bleeding gums, weak immunity)

Question 10

calcium deficiency

Answer 10

causes weak bones and rickets

Question 11

iron deficiency

Answer 11

leads to anemia (pale skin, tiredness)

Question 12

protein deficiency

Answer 12

leads to kwashiorkor (swollen abdomen, poor growth)

Question 13

type of malnutrition

Answer 13

1) obesity - excessive intake of fats and sugars
- lead to heart disease, diabetes
2) starvation - lack of food
- lead to muscle loss, weakened immune system

Question 14

ingestion

Answer 14

taking in of substances e.g food and drink into body

Question 15

digestion

Answer 15

break down of food

Question 16

egestion

Answer 16

removal of undigested food from the body as faeces

Question 17

assimilations point

Answer 17

nutrients are absorbed into the blood, which is then taken to the liver via Hepatic portal vein
(uptake and use of nutrients by cells)

Question 18

absorption

Answer 18

movement of nutrients from intestines to the blood

Question 19

alimentary canal

Answer 19

a long tube that runs from the mouth to the anus

Question 20

mouth

Answer 20

teeth bites into food to turn into smaller pieces
food mix with saliva and enzyme (amylase)
slides down oesophagus
salivary glands mix with saliva

Question 21

stomach

Answer 21

contains HCL to kill microorganisms
store food a long time and pass it to duodenum
strong muscular wall
contains goblet cell to secrete mucus

Question 22

small instestine

Answer 22

first part is duodenum, end part is ileum
ileum : absorbs digested nutrients into the blood
(diagram. wall made up of goblet cell, lacteal: absorbs fatty acids and glycerol, artery)

Question 23

large intestine

Answer 23

undigested food are egested out through the anus
absorb much water
it is made up of colon and rectum
rectum : stores undigested food as faeces

Question 24

bile function

Answer 24

• emulsifying fats and oils to increase the surface area for chemical digestion

Question 25

bile role

Answer 25

- bile is an alkaline substance produced by liver and stored in gallbladder - it is secreted into the small intestine, where it emulsifies fats (breaks it down to smaller droplets) - as enzymes in the small intestine work better in alkaline conditions, but food is acidic after being in stomach - increases enzyme activity of lipase

Question 26

physical digestion

Answer 26

the breakdown of food into smaller pieces without chemical change to the food molecules reason: increases the surface area of food for the action of enzymes in chemical digestion - doesn’t involve enzyme e.g teeth, bile

Question 27

human teeth diagram

Answer 27

teeth at below back - molars sharp teeth - canine teeth at front - incisors teeth at front back - pre molars