biology test

function of carbohydrate

short term energy

What is the pH of the stomach?

2 (acid)

What is an enzyme?

Catalyst that speeds up chemical reactions within being consumed.

What does protein digest into?

Amino acids

What do lipids digest into?

Fatty acids

What is digestion?

Breaking down big insoluble molecules into small soluble ones

What is absorption

Small molecules diffuse from intestine into blood

What is assimilation?

Making new substances from small soluble molecules.

What is egestion?

Removal of undigested waste

What is the order of digestion?

Ingestion, digestion, absorption, assimilation, egestion

What is ingestion?

Eating

What does maltase break down?

Maltose to glucose

What does Pepsin do?

Proteins into peptides

What does peptidase break down?

Peptides to amino acids

Where are enzymes released into?

Released into the duodenum via the pancreatic duct

How long is the ileum?

8m

How does food travel along the small intestine?

Peristalsis

What does lipase do?

Lipids to fatty acids and glycerol

What does amylase do?

Starch to Maltose

What does Trypsin do?

Proteins to peptides

Test for glucose

Benedict’s solution - add Benedict’s solution to the solution. Heat for 2 mins in a water bath at boiling point and look for a colour change

Test for starch

Iodine solution - add the iodine solution directly to the substance and look for a colour change

Test for protein

Biuret’s solution - add biuret’s solution to the solution and look for a colour change

Test for Lipids

Ethanol - add ethanol to the solution and shake thoroughly. Then add water and look for a colour change

How are villi adapted?

There are millions so it increases the surface area for absorption, very good blood supply, microvilli to increase surface area

function of proteins

growth and repair

function of lipids

long term energy storage

function of vitamin A

improves vision and keeps skin healthy

function of vitamin C

healthy skin and gums

function of vitamin D

strong bones and teeth

function of water

regulates body temperature

function of calcium

keeps bones and teeth strong; found in dairy products and fish

function of iron

needed for blood production (haemoglobin); found in red meat and liver

function of dietary fibre

provides bulk for the intestine to push food through it

types of food with carbohydrates

rice, bread, potatoes, pasta

types of food with protein

eggs, milk, fish, meat

types of food with lipids

oil, milk, nuts

types of food with vitamin A

liver, red/orange vegetables

types of food with vitamin C

citrus fruits, green vegetables

types of food with vitamin D

oily fish, fortified dairy

types of food with water

fruits, vegetables, drinks

types of food with calcium

dairy, fish with bones

types of food with iron

red meat, leafy greens

types of food with dietary fibre

whole grains, vegetables

deficiency of vitamin A

poor vision, dry skin

deficiency of vitamin C

scurvy (bleeding gums)

deficiency of vitamin D

rickets (soft bones)

deficiency of calcium

weak bones and teeth

deficiency of iron

anaemia (tiredness, pale skin)

balanced diet

diet containing all nutrients in correct proportions

malnutrition

poor diet leading to deficiency or excess of nutrients

obesity

too much fat caused by overeating / lack of exercise

starvation

severe lack of food leading to weight loss and organ failure

function of the mouth

mechanical digestion + amylase breaks starch to maltose

function of the oesophagus

peristalsis moves food to stomach

function of the stomach

churning + pepsin breaks proteins to peptides + HCl kills bacteria

function of the liver

makes bile to emulsify fats + neutralise stomach acid

function of the gall bladder

stores bile

function of the pancreas

makes amylase, lipase and trypsin

function of the small intestine

final digestion + nutrient absorption via villi

function of the large intestine

reabsorbs water

function of rectum

stores faeces

function of anus

egestion

bile function

emulsifies fats and neutralises stomach acid

peristalsis

muscular contractions pushing food along the gut

villi adaptations

large surface area, thin walls, good blood supply, microvilli

What are the two types of the small intestine?

Duodenum and Ileum

What is the main function of salivary amylase?

To clean the teeth after eating

Salivary amylase + starch =…

Maltose

Starch is digested into… then into…

maltose then glucose