Human nutrition Flashcards
Define balanced diet [7]
all of the food groups in the correct proportions
Carbohydrates
Proteins
Lipids
Vitamins
Minerals
Dietary Fibre
Water
Carbonhydrate
Energy
Bread pasta rice
Fats and oils
Insulation and energy store
Butter oil nuts
Proteins
Growth and repair
meat fish eggs
Vitamins C
Collagens protein
Makes up skin, hair, gum, bone
citrus fruit, strawberry, green vegetable
Vitamin D
Helps body absorb calcium
for strong bones and teeth
liver diary products oily fish
Calcium
Strong teeth and bone
milk cheese egg
Iron
Makes haemoglobin
liver red meat leafy greens
Fibre
Provides bulk for intestine to push through it
Vegetables, whole grains
Water
for chemical reactions to take place in cells
water juice milk
Causes of scurvy and rickets
Vitamin C deficent cause scurvy
Vitamin D deficent cause rickets
What are the 2 parts to the small intestine? describe what they do
1) Duodenum - Chemical digestion is completed
2) Ileum - Absorption of food molecules into blood due to the presence of villi
How is th ileum adapted and describt the effects [3]
1) it is very long
2) has a highly folded surface with millions of villi (tiny, finger like projections)
3) These adaptations increase the surface area of the ileum, allowing absorption to take place faster and more efficiently
How is the villi adapted? Describe the functions [4]
1) Epithelium is one cell thick, short distance for absorption by diffusion and active transport
2) Microvilli increase surface area
3) network of blood capillaries to maintain good blood supply for steep concentration gradient
4) Lacteal runs through the centre of the villus to transport fatty acids and glycerol into the lymph
Describe and the Function of teeth [2]
Physical digestion of food into smaller bits, teeth are embedded into gum and bone
Why is teeth useful [2]
1) Chew food into small bits increase surface area for enzyme to work on
2) Increase rate of digestion
Types of teeth
1) Incisor - front of the mouth
2) Canine - The pointed part in ur teeth 虎牙
3) Premolar
4) Molar
Function & Adaptation of incisor
1) Chisel shaped
2) Biting and cutting food
Function & Adaptation of canine
1) Pointed
2) Tearing, holding, biting
Function & Adaptation of premolar & molar
1) Large flat surfaces and ridges
2) Chewing and grinding
4 factors that change ur dietary needs
1) Age - energy need increases into adulthood then decreases as they age
2) Pregancy - Energy need increase to support foetus, calcium and iron needed to build bones, teeth, and blood
3) Breastfeeding - energy need increase and calcium needed to make high quality breast milk
4) Activity levels - More active = more energy need, muslces are contracting and resipiring faster
Scurvy cause & symptoms
1) severe vitamin C deficiency
2) Anemia
Exhaustion
Spontaneous bleeding
Pain in the limbs
Swelling
Gum ulcerations
Tooth loss
Rickets cause & symptoms
1) poor bone development caused by a severe lack of vitamin D
2) Symtpoms include:
Bone pain
Lack of bone growth
Soft, weak bones (sometimes causing deformities)