The Heart

Question 0

Describe the journey of blood around the body

Answer 0

1. De oxygenated blood returns from the body to the heart in a vein called th even cava
2. Blood from the body enters from the right atrium
3. When the walls of the heart contract the blood goes through a valve into the right ventricle
4. Then the ventricle contracts closing the valve and pumping blood through the pulmonary artery to the lungs
5. Blood is oxygenated in the lungs
6. Oxygenated blood returns from the lungs to the heart in the pulmonary vein
7. Blood first enters the left atrium
8. Heart contracts and then blood is pushed through a valve into the left ventricle
9. The ventricle contracts closing the valve and pumping the blood through n artery called the aorta to the body
10. Valves prevent the back flow of blood and the heart has it’s own bloody supply food and oxygen from the coronary artery

Question 1

In mammals what are transported in the blood?

Answer 1

Nutrients, oxygen, and carbon dioxide

Question 2

Describe arteries

Answer 2

Thick, muscular walls, narrow central channel and carry blood under high pressure away from the heart

Question 3

Describe veins

Answer 3

Carry blood under low pressure, have thinner walls and a wide central channel
Veins contains valves to prevent the backflow of blood towards the heart

Question 4

Describe capillaries

Answer 4

Networks at tissues and organs are thin walled and have a large surface area for the exchange of materials

Question 5

Describe red blood cells

Answer 5

Specialised
Bio concave in shape and have no nucleus and contain haemoglobin
This allows red blood cells to transport oxygen in the form of oxyhemoglobin