nutrition in humanz

Question 1

carbs

Answer 1

source-
bread, pasta, rice, sugary food
function-
energy

Question 2

protein

Answer 2

source-
meat, fish, dairy products
function-
growth and repair

Question 3

lipids

Answer 3

source-
butter, oil
functions-
energy store and insulation

Question 4

vitamin A

Answer 4

source-
carrots
function-
improving vision in dim light
healthy skin and hair

Question 5

vitamin C

Answer 5

sources-
citrus fruits
function-
prevents scurvy

Question 6

calcium

Answer 6

sources-
dairy
function-
making strong bones and teeth

Question 7

iron

Answer 7

sources-
red meat
function-
making haemoglobin for healthy red blood cells

Question 8

water

Answer 8

source-
all drinks
function-
chemical reactions in cells
replace water lost in urine and sweat

Question 9

fibre

Answer 9

sources-
fruit, veg, wholegrain
functions-
prevents constipation

Question 10

vitamin D

Answer 10

sources-
our skin (when exposed to sunlight)
function-
calcium absorption

Question 11

ingestion

Answer 11

taking food into the body

Question 12

peristalsis

Answer 12

movement of food through the alimentary canal caused by the contractions of muscles in the walls

Question 13

digestion

Answer 13

breaking down large insoluble food molecules into small soluble ones which can be absorbed

Question 14

absorption

Answer 14

movements of small, soluble products of digestion into the blood

Question 15

egestion

Answer 15

removal of undigested material (faeces) from the body

this waste has never entered your body cells

Question 16

assimilation

Answer 16

body cells using the small molecules produced by digestion to make large molecules

Question 17

mouth

Answer 17

teeth- chew food
saliva- lubricates food
amylase- in saliva begins to beak down starch into maltose

Question 18

oesophagus

Answer 18

each bolus of food is moved to the mouth ton stomach by peristalsis

Question 19

stomach

Answer 19

CHEMICAL-
-walls secrete protease (begins to break down protein into amino acids)
-acid provides optimum pH for protease enzyme
-acid kills microorganisms ingested with food
PHYSICAL-
muscular walls pummel the food

Question 20

pancreas

Answer 20

-produces digestive enzymes and secretes them into small intestine
-no food passes here
but essential for digestion

Question 21

small intestine

Answer 21

contains all digestive enzymes (amylase, protease, lipase, maltase)

• amylase breaks down starch into maltose, then broken down by maltase into glucose
• protease breaks down proteins into amino aids
• lipase breaks down lipids into fatty acids and glyderol
• digested food is absorbed into the blood

Question 22

large intestine

Answer 22

• water is absorbed

- faeces are stored before being egested

Question 23

bile

Answer 23

• made by liver
• stored in gall bladder
• ITS ALKALINE so NEUTRALISES STOMACH ACIDS from stomach providing optimum pH for enzymes in small intestine
• EMULSIFIES LIPIDS increasing total surface area of fats for lipase enzymes to work on, increasing rate o fat digestion

Question 24

peristalsis

Answer 24

1) there’s muscular tissue all the way down the alimentary canal
2) it squeezes boluses through gut, so it doesn’t get clogged up
3) this action of waves of circular muscle contractions is called peristalsis

Question 25

villus & micro-villus in small intestine

Answer 25

the small intestine is very long and is lined with villi and micro-villi (finger-like projections) this INCREASES SURFACE AREA, INCREASING THE RATE OF DIFFUSION ACROSS THE SURFACE.

each villus is covered in a thin layer of cells so digested food doesn’t have to travel far.
each has on capillaries so digested food can enter blood.
fresh blood flows through the capillaries keeping concentration gradient between SI and blood high as possible.
each villus contains LACTEAL to carry away fat products.