Effect of Exercises

Circulation, Exercises and Coronary Heart Disease

Exploring how the heart rate changes during exercise and under the influence of adrenaline

Effect of exercise

* During exercise, the muscle cells need more energy than usual as they are contracting more. * They therefore need to respire more and so need more oxygen and glucose, and produce more waste carbon dioxide.

To meet this demand, the heart:

* contracts more often – the heart rate increases

* contracts more powerfully – the stroke volume increases, pumping a greater volume of blood with each beat.

After exercise has finished ...

* the heart rate takes several minutes to return to its normal resting rate. 

* This is needed to repay the oxygen debt built up during exercise if the muscles respired anaerobically and produced lactic acid

* The oxygen is needed to combine with the lactic acid (a toxic substance) and break it down into carbon dioxide and water.

Effect of adrenaline

* Adrenaline is a hormone secreted when we are afraid, stressed or angry .

* It also causes the heart rate and stroke volume to increase to prepare our body for ‘fight or flight’

* In addition it diverts blood away from non essential areas of the body (like the digestive system) so that more is available to supply muscles – this is why we get ‘butterflies’ in our stomach when we are nervous .

Multiple Choice

Which of these is a immediate effect of physical exercise?

• Increased Heart Rate

• Increase in aerobic fitness

• Improvement in stamina

Multiple Choice

During exercise, your breathing rate increased in order to accommodate:

• Increased carbon dioxide needs of your muscles

• Increased oxygen needs of your heart

• Increased oxygen needs of your muscles

• Increased carbon dioxide needs of your lungs

Multiple Choice

Which type of respiration produces more energy?

• aerobic

• anaerobic

Coronary Heart Disease

* The heart is made of muscle cells

that need their own supply of blood .

* The blood is supplied to the heart muscle by the coronary arteries

* If a coronary artery becomes partially or completely blocked by fatty deposits called ‘plaques’, cells in that area of the heart will

not be able to respire and can no longer contract, leading to a heart attack .

Causes of Coronary Heart disease:

Blood Vessels

There are 3 types of blood vessels:

- arteries

- veins

- capillaries

Arteries

- Carry blood at high pressure away from the heart 

- Carry oxygenated blood (other than the pulmonary artery)

- Have thick muscular walls containing elastic fibres (to withstand high pressure)

- Have a narrow lumen (to maintain high pressure)

- Speed of flow is fast

Veins

- Carry blood at low pressure towards the heart 

- Carry de oxygenated blood (other than the pulmonary vein)

- Have thin walls 

- Have a large lumen (as blood pressure is low) - Contain valves to prevent the backflow of blood as it is under low pressure

- Speed of flow is slow

Capillaries

- Carry blood at low pressure within tissues

- Carry both oxygenated and deoxygenated blood

- Have walls that are one cell thick so that substances can easily diffuse in and out of them

- Have ‘leaky’ walls so that blood plasma can leak out and form tissue fluid surrounding cells

- Speed of flow is slow

How arteries, veins and capillaries are connected

general structure of the circulation system

* Blood is carried away from the heart and towards organs in arteries

* These narrow to arterioles and then capillaries as they pass through the organ

* The capillaries widen to venules and finally veins as they move away from the organs

* Veins carry blood back towards the heart

Multiple Choice

Which of the following shows a correct route for the exchange of substances in blood?

• arteriole --> artery --> capillary --> vein --> venule

• artery --> vein --> capillary --> venule --> arteriole

• venule --> vein --> capillary --> artery --> arteriole

• artery --> arteriole --> capillary --> venule --> vein

Multiple Select

Which of the following is/are true of an arteriole?

One, some or all answers could be correct?

• It is a small artery

• It connects arteries to capillaries

• It contains smooth muscle that can contract and relax

• It controls blood flow to different organs by changing its diameter

Multiple Select

Which of the following is/are true of a venule?

One, some or all answers could be correct?

• It is a small vein

• It connects arteries to capillaries

• It ensures that blood containing wastes is taken away from organs by veins

• It usually carries oxygenated blood

Multiple Select

Veins have valves that prevent blood from falling backwards.

Why would this happen if there were no valves?

One, some or all answers could be correct?

• Blood is much heavier in veins

• Blood in veins is at a lower pressure

• Gravity is in the opposite direction to the flow of blood

• Blood is much thicker in veins

Multiple Select

Arteries have a thick layer of muscle and elastic tissue.

Why is this important?

One, some or all answers could be correct?

• Prevents arteries from bursting due to high blood pressure

• Smooths out blood flow so it is in pulses

• Helps to force blood back to the heart

• Helps the artery to pick up oxygen

Multiple Select

Which of the following is true of a vein?

One, some or all answers could be correct?

• it carries blood at a high pressure

• it always carries deoxygenated blood

• it carries blood away from the heart

• it contains valves

Multiple Select

Which of the following is true of a vein?

One, some or all answers could be correct?

• it carries blood back to the heart

• it has a thick layer of elastic tissue

• it has a thin layer of muscle tissue

• it has a wide lumen

Multiple Select

Which of the following is true of an artery?

One, some or all answers could be correct?

• it carries blood at a high pressure

• it always carries oxygenated blood

• it carries blood away from the heart

• it has an outer layer of connective tissue

Multiple Select

Which of the following is true of an artery?

One, some or all answers could be correct?

• it carries blood back to the heart

• it has a thick layer of elastic tissue

• it has a thin layer of muscle tissue

• it has a narrow lumen

Multiple Choice

Which is the largest vein in the body?

• Aorta 
• Arteriole 
• Superior Vena Cava 

Multiple Choice

A system of the body which pumps blood from the left ventricle of the heart to the Aorta and the rest of the body. 

• Systemic
• Pulmonary

Multiple Choice

Carry oxygenated blood back to the heart, only type of these to do this:

• pulmonary arteries
• pulmonary veins
• pulmonary capillaries
• aorta artery

Multiple Choice

Largest artery in the human body:

• Pulmonary artery
• femoral artery
• aorta
• carotid artery

Multiple Choice

These are one cell thick

• arteries

• capillaries

• veins

Multiple Choice

which of the blood vessels do you think have greatest blood pressure

• veins

• capillaries

• atria

• arteries

Multiple Choice

Valves in veins

• support them

• protect them

• prevent the backward movement inside them

• provide them elesticity

Multiple Choice

The blood vessel that has valves at intervals...

• capillary

• artery

• vein

• none of the above

Multiple Choice

The blood vessel that has the largest diameter is

• vein

• artery

• capillary

Multiple Choice

The thickest and strongest blood vessel is the

• vein

• artery

• capillary

• both veins and capillaries

Multiple Choice

Which blood vessel has valves to prevent the back-flow of blood?

• Veins

• Arteries

• Capillaries

Multiple Choice

What type of blood do the arteries usually carry?

• Oxygenated Blood

• Deoxygenated Blood

Multiple Choice

Which is the smallest of the 3 blood vessels?

• Veins

• Arteries

• Capillaries

Multiple Choice

Which blood vessels take blood AWAY from the heart?

• Veins

• Arteries

• Capillaries

Multiple Choice

Which blood vessels take blood TO the heart?

• Veins

• Arteries

• Capillaries

Multiple Choice

Which of the following is NOT a type of blood vessel?

• Artery

• Capillary

• Vein

• Ventricle