8A Food and
Nutrition
1. Nutrients
The food that you eatprovides the raw materials
your body needs for energy.
Food substances that
provide the raw materialsNutrients
carbohydrates, fats,
proteins, vitamins, minerals
Carbohydrates Starch and sugars
Liquid fats are oils. Fats and
Fats
oils are called lipids.
Made of plant cell walls- not
used by the body. Helps food
Fibre
move through the intestines
and stops them getting
blocked.
• a lubricant
• dissolves substances to be
Uses of
carried around body
Water
• fills up cells, holding shape
• sweat to cool you down
Show the amounts of
Food Labels
different nutrients in food.
Add 2 drops of iodine. If it
Starch Food
turns blue-black starch is
Test
present.
Add 5 drops of biuret
Protein Food
solution. If it turns purple
Test
protein is present.
Rub on some white paper
Fat Food Test and hold up to the light. fats
will leave a greasy mark
Diet
2. Uses of Nutrients
The body’s main source of
Uses of
energy.
Carbohydrates
Bread, potatoes, pasta
Another source of energy
that is stored in your body.
Uses of Fats
Some is stored under the
skin to insulate the body.
Dairy products, fried food
The amount of fuel you use
Maintaining
needs to balanced by the
Mass
amount you eat.
The units for measuring the
Kilojoules (kJ)
energy in food.
The process that releases
Respiration
energy from food.
Depends on age, sex and
Energy Needs
how active you are.
Make new cells allowing us
to grow and repair our
Uses of
bodies.
Proteins
Meat, fish, cheese, beans,
milk
Uses of
Used in small amounts to
Vitamins and
maintain health.
Minerals
Needed for healthy skin
Vitamin A
and eyes.
Helps cells in tissues stick
Vitamin C
together properly.
Calcium
Needed to make bones.
Iron
Makes red blood cells.
Lack of calcium / vitamin D
causing bones not to form
properly.
Lack of iron causing tiredness
Anaemia
and shortness of breath.
Lacking nearly all nutrients
Starvation
needed.
Caused by eating food
Obesity
containing more energy than
you need.
Fat clogs arteries so little
Heart Attack
blood reaches the heart.
Reference
How much of each nutrient
Intakes
should be eaten in a day.
Rickets
Eating a range of foods in the
right amounts.
Having too much / too little
Malnutrition
of a nutrient in your diet.
Deficiency Caused by lacking certain
Disease
nutrients for a long time.
Lack of protein causing a ‘pot
Kwashiorkor
belly’.
Night
Lack of vitamin A.
Blindness
Lack of vitamin C causing
Scurvy
painful joints and bleeding
gums.
5. Absorption
Digesting
Starch
4. Digestion
Turning large insoluble
molecules into small soluble
ones.
Digestive System
Digestion
3. Balanced Diets
Balanced
Diets
Faeces pushed out bodyegestion.
Microorganisms needed to
Gut Bacteria
help digest food.
Substances that speed up
the breaking down of large
Enzymes
molecules- biological
catalysts.
Anus
Mouth
Gullet
Stomach
Small
Intestine
Large
Intestine
Rectum
Teeth grind food and saliva
helps digest food.
(oesophagus / food pipe)
Muscles contract pushing
the food down.
Food churned with acid.
More digestive juices addedsmall digested molecules
absorbed into body.
Water is removed from
undigested food- faeces
formed.
Stores faeces
Digested nutrients dissolve in
the blood plasma and are
Blood
carried around the body to
cells.
Movement of particles from
Diffusion
an area of high concentration
to low concentration.
Has lots of tiny finger-shaped
villi to increase surface area.
Small
Each villus has a folded top
Intestine
that forms microvilli. Villi
Adaptations.
walls are one cell thick for
easier diffusion.
Causes fewer digestive
Alcohol
enzymes to be released and
can damage villi.
Lesson
1. Nutrients
2. Uses of Nutrients
3. Balanced Diets
4. Digestion
5. Absorption
Memorised?