AQA GCSE Combined science Biology - organisation, enzymes and the circulatory system

organisation, enzymes and the circulatory system

What is a tissue?

a group of cells working together

What is an organ?

a group of tissues working together

What is an organ system?

a group of organs working together

What is the function of the digestive system?

To break down large, insoluble food molecules into small, soluble ones for absorption.

What enzyme breaks down carbohydrates?

Amylase.

Where is amylase produced?

Salivary glands, pancreas, small intestine.

What enzyme breaks down proteins?

Protease.

Where is protease produced?

Stomach, pancreas, small intestine.

What enzyme breaks down lipids (fats)?

Lipase.

Where is lipase produced?

Pancreas and small intestine.

What does bile do?

Neutralises stomach acid and emulsifies fats to increase surface area for enzymes.

Where is bile made and stored?

Made in the liver, stored in the gallbladder.

What is the role of the heart?

To pump blood around the body.

Name the four chambers of the heart.

Left atrium, right atrium, left ventricle, right ventricle.

Which side of the heart pumps oxygenated blood?

The left side.

What are the three types of blood vessels?

Arteries, veins, capillaries.

What are the functions of arteries?

Carry blood away from the heart under high pressure.

What are the functions of veins?

Carry blood to the heart under low pressure, contain valves.

What are the functions of capillaries?

Exchange of substances between blood and tissues.

What is the function of red blood cells?

Carry oxygen using haemoglobin.

What is the function of white blood cells?

Defend the body against pathogens.

What is the function of platelets?

Help blood to clot at wounds.

What is coronary heart disease?

Layers of fatty material build up in the coronary arteries, reducing blood flow.

What are stents and how do they help?

Tubes inserted into arteries to keep them open and maintain blood flow.

What is a statin?

A drug used to reduce cholesterol levels in the blood.