4.1 Oxygen in the Blood

Question 1

What is myoglobin?

Answer 1

Pigment containing haem found in muscles

Question 2

How many molecules of oxygen can bind to myoglobin?

Answer 2

1

Question 3

When does myoglobin release its oxygen molecule?

Answer 3

When pO2 is very low eg. exercise

Question 4

How many oxygen molecules can haemoglobin bind to?

Answer 4

4

Question 5

Why is the haemoglobin dissociation curve sigmoidal?

Answer 5

As more oxygen molecules bind it becomes more likely to accept other oxygen molecules

Question 6

What is the Bohr Shift?

Answer 6

Allows more O2 to be given up in tissues which need it more eg. metabolically active tissues

Question 7

What is 2-3-BPG?

Answer 7

Shifts dissociation curve to the right. Allows more O2 to be given off at the tissues.

Question 8

Why is CO poisonous?

Answer 8

CO binds with haemoglobin with a stronger affinity than O2 so O2 is not transported and not given up as readily at the tissues.

Question 9

What is cyanosis?

Answer 9

A bluish colour to the skin due to unsaturated haemoglobin. Occurs when insufficient oxygen is reaching the tissues

Question 10

What is pulse oximetry?

Answer 10

Detects the level of Hb saturation using infrared light.