electricity, digestive system, ecosystem

Question 1

what function does the mouth have

Answer 1

• breaks down food into smaller pieces
• salivary glands secrete saliva which contains the enzyme, salivary amylase
• tongue rolls the food into small balls and pushes it down to the oesophagus

Question 2

oesophagus function

Answer 2

• a muscular tube measuring about 25cm
• transports food from the mouth to the stomach
• no secretion of enzymes in the oesophagus

Question 3

stomach funtion

Answer 3

• churns to break down food into even smaller pieces
• secretes gastric juices containing; the enzyme, protease and hydrochloric acid that kills harmful microorganisms in food

Question 4

large intestine function

Answer 4

• absorbs liquid and mineral salts from undigested food

- bacteria in the colon make vitamins for the body

Question 5

small intestine functions

Answer 5

• food is mixed with intestinal juice, pancreatic juice, and bile to help digestion
• the liver and pancreas are connected to the small intestine
• the final products of digestion are absorbed into the bloodstream

Question 6

rectum function

Answer 6

• temporarily stores the remaining undigested food

- faeces leaves the body through the anus

Question 7

liver function

Answer 7

the cells in the liver secretes bile

Question 8

gall bladder function

Answer 8

stores bile produced by liver

Question 9

pancreas function and enzymes

Answer 9

secretes pancreatic juice containing enzymes which helps digest food

• pancreatic amylase
• pancreatic protease
• pancreatic lipase

Question 10

carbohydrates nutrients

Answer 10

• large molecules: starch, cellulose, and glycogen
• small molecules: glucose, galactose, and fructose <- these are also known as sugars
• simplest building block -> glucose

Question 11

carbohydrates function

Answer 11

• provides immediate source of energy

- cellulose makes up part of the fibre that passes out undigested and forms the bulk in our faeces

Question 12

example foods of carbohydrates

Answer 12

starch, cellulose (plants, vegetables), sugars (sucrose found in sweet fruits, lactose in milk)

Question 13

nutrients in proteins

Answer 13

• amino acids
• generally large molecules
• simplest building block -> amino acid

Question 14

protein functions

Answer 14

• to make new cells for body growth and to repair worn out tissue
• to make complex proteins called enzymes

Question 15

protein food examples

Answer 15

meat, fish, eggs, milk, yogurt

Question 16

nutrients in fat

Answer 16

• made up of glycerol and fatty acids

- large molecules that are insoluble in water

Question 17

fat function

Answer 17

• source and store of energy

- act as an insulating material to prevent excessive heat loss

Question 18

fat food example

Answer 18

butter and cheese

Question 19

why must food be digested

Answer 19

• the cell surface membranes of our cells in the body are partially permeable
• large molecules like starch, proteins, and fats cannot pass through the cell surface membranes
• digestion breaks down the large, insoluble molecules into small, soluble molecules
• these small molecules can pass through the cell surface membranes

Question 20

what are enzymes

Answer 20

• complex proteins that speed up the rate of chemical reactions
• enzymes remain unchanged at the end of chemical reactions
• example of chemical reaction is large insoluble food molecules being broken down into smaller and soluble food molecules during digestion
• enzymes that act on food molecules are called digestive enzymes; which allow digestion to occur faster

Question 21

what does amylase work on

Answer 21

starch (amylose)

Question 22

what does maltase work on

Answer 22

maltose

Question 23

what does protease work on

Answer 23

proteins (proteins digested by protease to form amino acids)

Question 24

what does lipase work on

Answer 24

fats/lipids

Question 25

what does sucrease work on

Answer 25

sucrose

Question 26

what does saliva work on

Answer 26

saliva has salivary amylase

salivary amylase acts on starch

Question 27

what does gastric juice act on

Answer 27

gastric juice contains protease

protease acts on proteins

Question 28

what pancreatic juice act on

Answer 28

there is pancreatic amylase, pancreatic protease, and pancreatic lipase found in pancreatic juice
amylase works on starch
protease works on proteins
lipase works on fats

Question 29

what does intestinal juice act on

Answer 29

intestinal juice has maltase, protease, and lipase
maltase acts on maltose
protease acts on proteins
lipase acts on fats

Question 30

what does bile act on

Answer 30

it is made in the liver and acts on fats

it is not an enzyme and only helps with digestion, it does not digest anything

Question 31

what is bile

Answer 31

bile is a yellow fluid produced by the liver, then stored in the gall bladder
bile physically breaks down large droplets of fat into smaller droplets of fat
this process is called emulsification

Question 32

what does fat turn into

Answer 32

intestinal and pancreatic lipase act on fats and becomes fatty acids + glycerol

Question 33

what does starch turn into

Answer 33

salivary amylase and pancreatic amylase act on starch, which becomes maltose
maltase then works on maltose and turns it into glucose

Question 34

what do proteins turn into

Answer 34

protease acts on proteins, turning them into amino acids

Question 35

absorption in the small intestine

Answer 35

• only small food molecules can pass through the walls of the small intestine and blood vessels
• the small food molecules enter the bloodstream and are transported throughout the body
• the small food molecules are absorbed by body cells to be used for respiration, cell repair and other processes

Question 36

what physical digestion does the mouth do

Answer 36

teeth grinds food into smaller pieces

Question 37

what chemical digestion does the mouth do

Answer 37

salivary amylase digests starch

Question 38

what physical digestion does the stomach do

Answer 38

stomach muscles churn to digest food

Question 39

what chemical digestion does the stomach do

Answer 39

protease digests proteins

hydrochloric acid kills harmful microorganisms

Question 40

what physical digestion does the small intestine do

Answer 40

bile emulsifies fats

Question 41

what chemical digestion does the small intestine do

Answer 41

starch and proteins are further digested and fat digestion begins

Question 42

why cant fibre be digested

Answer 42

it forms the bulk in our faeces