To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

Transport of Oxygen and Carbon Dioxide

Lesson Objective : To describe and explain how oxygen and carbon dioxide are carried in

blood and the effect of exercise

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

Blood Composition

• What is in blood?– 55% Plasma– 45% Red Blood Cells

(Erythrocytes)– <1% White Blood Cells

(Leukocytes) & Platelets

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

Oxygen Transport

In Solution…• 0.3ml per 100ml

– Not very soluble

• Average blood volume = 5 litres– 15ml of oxygen– 4 seconds– Or 80 litres/minute at rest

• Physiologically important

with Haemoglobin…• Protein containing iron• Sup up Oxygen carrying

capacity– 60-70 times– 197ml/litre

KEY POINT

O2 transported in 2 ways

1. 3% In solution

2. 97% with haemoglobin

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

Haemoglobin

• Has 4 Iron molecules that can attract 4 oxygen molecules

Hb4 + 4O2 Hb4O8

• Oxyhaemoglobin• Depends on partial

pressure of oxygen

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

Carbon Dioxide Transport

In solution…• 5%• Physiologically important

With water…• 70%• Carbonic Acid• Slow process• Carbonic Anhydrase

speeds up x 5000

With haemoglobin…• 25%• Carboaminohaemoglobin

• Partial Pressure of O2

• Partial Pressure of CO2 CO2 transported in 3 ways

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

Oxygen-Haemoglobin Dissociation Curve!

Blood Oxygen Capacity = Hb (g) x O2 in Hb15g of Hb / 100ml

1.34ml of oxygen / Hb g

Answer is…20ml of oxygen per 100ml of blood when

breathing ambient air at sea level

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

Your Mission

Haemoglobin is not always saturated or associated with oxygen

1. Look at the ‘x’ axis on the following graph what does it show?

2. Draw a line up from 100 the axis to intersect the curve and then across to the ‘y’ axis. What is the % Saturation?

3. Do the same from 40. What is the % Saturation?

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

You should have this…

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

The Bohr-ing Effect of Exercise

To get more oxygen dissociation we need the graph to move down and right

1. Increase in blood & muscle temperature

2. Decrease in PPO2 within muscle

3. Increase in PPCO2 within muscle4. Increase in acidity

THE BOHR EFFECTTHE BOHR EFFECT

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

To describe and explain how O2 and CO2 are carried in blood and the effect of exercise

Pupil Tasksheet