B3 - Organisation And The Digestive System

Question 1

What is tissue?

Answer 1

It is a group of cells with similar structure and function working together

Question 2

What is an organ?

Answer 2

Organs are a collection of tissue that work together to perform a specific function

Question 3

What are organ systems?

Answer 3

It is a group pf organs that work together to perform a specific function

Question 4

What are the main parts of the digestive system?

Answer 4

Mouth, gullet, diaphragm, stomach, liver, gall bladder, pancreas, duodenum, large intestine, small intestine, bile duct, appendix, rectum, anus.

Question 5

What are carbohydrates?

Answer 5

• carbohydrates are made up of chains of simple sugars like glucose and fructose
• food like pasta, potatoes and bread

Question 6

What are proteins?

Answer 6

• proteins are used for building and repairing your body as well as being the base of all the enzymes
• proteins are made up of long chains of amino acids

Question 7

What are lipids?

Answer 7

• these are important energy stores

- they are made up of 3 molecules of fatty acids joined to a molecule of glycerol

Question 8

What are catalysts?

Answer 8

Catalysts are chemicals use to speed up chemical reactions.

Question 9

What is the lock and key theory?

Answer 9

This is the theory that the enzyme and the substrate fit together like a lock and key. The substrate connects with the right enzymes active site.

Question 10

What is metabolism?

Answer 10

The sum of all the reaction in a cell or in the body

Question 11

How does the temperature affect enzyme action?

Answer 11

The rate of reaction increases with the temperature
Then the optimum temperature is reached with the highest rate of reaction
As it gets too hot, the structure of the active site denatures meaning the substrate does not fit

Question 12

How does pH affect the enzyme action?

Answer 12

• as the pH rises, the rate of reaction does as well
• it reaches an optimum pH of just below 5
• it starts to denature as the pH increases from there meaning the rate of reaction declines

Question 13

What are the main enzymes called?

Answer 13

Lipase, carbohydrase, amylase(a type of carbohydrase) and protease.

Question 14

Where are carbohyrase created?

Answer 14

Salivary gland and the pancreas

Question 15

Where is protease created?

Answer 15

Stomach, small intestine, Pancreas

Question 16

Where is lipase created?

Answer 16

Small intestine, pancreas

Question 17

What is the main function of fibre?

Answer 17

Aids in Peristalsis of the gut and keepst the bowels healthy

Question 18

What is the function of bile?

Answer 18

To emulsify the lipids (break them down) and ajust pH (its an alkali)

Question 19

What is the test for starch?

Answer 19

Add a few drops of iodine
Positive result: food goes blue/black
Negative result: food stays the same or is tinged red/yellow from the iodine

Question 20

What is the test for sugar?

Answer 20

Add benedicts solution enough to cover the food and then heat in warm water bath for 10 mins
Positive Result: Solution turns brick red
Negative Result: Solution satys blue

Question 21

What is the test for lipids?

Answer 21

Add a few drops of ethanol and shake. Leave for a minute and add water
Positive Result: Becomes cloudy white layer

Question 22

What is the test for protein?

Answer 22

Add Biuret Solution/Sodium hydroxide to food and then add some copper sulphate solution.
Positive Result: Solution becomes purple