Unit 3

Question 1

Describe how AV valve maintain a unidirectional flow of blood

Answer 1

• pressure in the atria higher than the ventricles causing the AV valves to open
• pressure in the ventricles higher than the atria causing the AV valves to close

Question 2

Describe the process of facilitated diffusion

Answer 2

• movement of charged particles
• down a concentration gradient via carrier and channel proteins

Question 3

Describe the process of active transport

Answer 3

• movement against concentration gradient
• via carrier proteins using ATP