What does the pancreas do? 

Creates enzymes 

What does the liver do? 

Makes bile 

What does the gall bladder do? 

Stores bile 

What does the bile duct do? 

Allows bile to travel to the small intestine 

What happens in the small intestine? 

Food is digested and absorbed into blood 

What happens in the large intestine? 

Water and minerals absorbed into the blood 

What does the mouth do? 

Food is chewed 

What do the salivary glands do? 

Add enzymes 

What does the gullet do? 

Carries food to the stomach 

What does the rectum do? 

Stores faeces 

What does the anus do? 

Expels faeces 

Why does villi cover the small intestine wall? 

So that more nutrients can be absorbed 

What are the levels of organisation for multicellular organisms? 

Cell→ tissue→ organ→ organ system → multicellular organism  

What are the three types of enzyme in digestion? 

Carbohydrase, protease, lipase 

What does carbohydrates turn into with the help of an enzyme?  

Sugars 

What does proteins turn into with the help of an enzyme? 

Amino acids 

What does lipase turn into with the help of an enzyme? 

Fatty acids and glycerol 

What is a biological catalyst? 

Something that speeds up digestion without being used up. 

What is a producer? 

An organism that makes their own food by photosynthesis 

What is the word equation for photosynthesis? 

Carbon dioxide + water → glucose + oxygen 

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How are digestive enzymes used commercially? 

Enzymes in washing powders help remove stains by breaking down the stains into water-soluble substances.  

What can greasy stains be removed by? 

Lipase 

What can protein stains be removed by? 

Protease 

What are the advantages of using enzymes in washing powder? 

• They work at low temperatures which otherwise might need a high temperature 

• Energy and money saved by allowing clothes to be washed at a low temperature.  

• Helps clean delicate fabrics that would otherwise be damaged on hot wash 

  What are the disadvantages of using enzymes in washing powder? 

• Some people have allergic reactions to biological detergent  

• Protease enzymes can damage protein fibres in natural fabrics such as silk and wool 

What are exchange surfaces? 

Where materials are exchanged with the environment. 

What are the key features of an exchange surface? 

• Thin 

• Large surface area 

• Good blood supply 

What does the waxy layer do in a leaf? 

Protects the leaf and prevents water loss without blocking the light 

What does the epidermis layer do in a leaf? 

Transparent layer of cells that allow light to reach the cells below. It prevents water loss and is a barrier for infection 

What does the palisade mesophyll layer do in a leaf? 

Where most of the photosynthesis occurs. Packed with many chloroplasts. Arranged close so that lots of light can be absorbed. 

What does the spongy mesophyll layer do in a leaf? 

Where gas exchange occurs. It is loosely packed to allow carbon dioxide and oxygen to diffuse in and out of the leaf. 

What does stomata do? 

Allows gasses to enter and leave a leaf 

What do guard cells do? 

Open stomata during the day and close them at night 

What does the circulatory system do? 

Transports oxygen and glucose around your body 

What are blood vessels? 

Tube like structures that transport blood around the body.  

What is the lumen? 

The hollow central cavity in which blood flows. 

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What is the function of the arteries? 

Carry blood away from your heart 

What is the function of the veins? 

Carries blood back to the heart 

What is the function of the capillaries? 

Link the arteries to the veins 

Are arteries strong or weak? 

Strong because when the heart beats it forces the blood through them at high pressure. 

Are veins strong or weak? 

Weak the blood pressure is lower than the arteries 

Do arteries have thick walls? 

Yes 

Do capillaries have thick walls? 

Very thin only a cell thick 

Do veins have thick walls? 

Relatively thin walls 

Do veins have small or large lumen? 

large 

Do arteries have small or large lumen? 

small 

Do capillaries have small or large lumen? 

narrow 

What is a double circulatory system? 

Blood flows through the heart twice during each circuit of the body 

What are the four chambers in your heart? 

Right atrium, left atrium, left ventricle, right ventricle 

What muscle is the heart made of? 

Cardiac muscle 

How does a heartbeat work? 

Many cardiac muscle cells contract together to produce a heartbeat 

What is transpiration? 

The loss of water vapor. 

Where does transpiration mainly happen? 

The leaves of a plant 

What is the transpiration stream? 

The constant flow of water from the roots  

Where does the transpiration stream happen? 

through the stem and xylem vessels and out the leaves 

What are the four steps for the transpiration stream ? 

1. Water moves into the roots by osmosis. It replaces the water constantly moving up the stem 

2. Water moves up from the roots into the stem 

3. Water moves up through the stem and into the leaves to replace the water lost by transpiration 

4. Water vapor is lost from the leaves by transpiration through open stomata 

Does loss of water increase pressure at the top of the xylem vessels. 

No, it reduces the pressure 

Why does stomata open? 

When there is plenty of light and water the guard cells take up water by osmosis. This makes them swell up, opening the stomata 

Why does stomata close? 

When conditions for photosynthesis are not good the guard cells lose water. They become floppy and the stomata close. This helps the plant to reduce water loss.