Cardiovascular System Flashcards
Function
Transport of nutrients
Removal of waste
clotting
temperature regulation
Blood is made from
Plasma (55%)
platelets (less than 1%)
red blood cells (45%)
high white blood cells (less than 1%)
What is plasma
A yellowish liquid
What does plasma have dissolved in it
Glucose and other nutrients from digested food
hormones
carbon dioxide and other waste from cells
What do red blood cells do
- Red blood cells or the oxygen carriers
- they contain haemoglobin which combines with oxygen
- haemoglobin gives them their in the red colour
- There made in the bone marrow
What do white blood cells do
Defend your body against disease
Difference between white blood cells and red blood cells
They are larger than red blood cells and have a nucleus
Where are white blood cells made
Red bone marrow
Lymph nodes
Spleen
What are phagocytes
Are white cells that change shape to surround germs and produce enzymes to kill and digest them
What are antibodies
They are chemicals that destroy germs
Platelets
Platelets are fragments from special cells made in the bone marrow
- they stick to each other easily
- their job is to stop you losing blood by making a clot
What makes up your circulatory system
Blood
Heart
Blood vessels
What does the right side of the heart do
Pumps blood to the lungs to pick up oxygen
The left side of the heart …….
Pumps oxygenated blood around the rest of the body
What do arteries do
Carry blood away from the heart
What is the largest artery
Aorta
What blood vessels carry blood to t he heart
Veins
What is the largest vein
Vena cava
The heart has …… chambers
4
The upper chamber is called
Atria
The Lower chambers are
Ventricles
The wall of the heart is made of ……… muscle
Cardiac
The wall down the middle is called the ………
Septum
Why does the heart have valves
To stop blood flowing backwards
The heart is called a ……….. pump
Double pump
Heart rate
also called the pulse and represents the number of cardiac cycles per minute
Stroke volume
The amount of blood pumped from the left ventricle per heartbeat
Cardiac output
The volume of blood pumped out of the left side of the year per minute
Cardiac output=
Heart rate x stroke volume
Pathway of the blood
Right atrium - tricuspid valve - pulmonary artery- lungs - pulmonary vein - heart - mitral valve - left ventricle. - aorta - around the body - vena cava
Short term effects of exercise
- Cardiac output increases
- Vasoconstriction and vasodilation
Explain why cardiac output increases
When you exercise, adrenaline is released causing the heart rate to rise
- as blood is pumped faster, there is an increase causing the heart rate to rise
- this increases blood pressure
- so cardiac output increases
- overall, this means more nutrients are delivered to the working muscles and more waste gets away
Vasoconstriction and vasodilation explain
Vasoconstriction restricts the blood flow to an area
- vasodilation increases blood flow to an area
- at rest the muscles need 15-20% of the blood but this increases to 85% during exercise
- so vasodilation occurs to divert the blood away from the organs and towards the muscles
- this is known as the redistribution of blood
Long-term effects
- The heart becomes larger with thicker and stronger muscular walls. The left ventricle is able to empty more forcibly pumping more blood out each beat. The heart chambers also become larger, holding more blood. The increased stroke volume means the heart rate when resting will be lower
- the arteries also become larger and more elastic which make them more efficient in carrying the blood supply during exercise
- more capillaries develop in the muscle (capillarisation) bringing more oxygen and nutrients
- more red blood cells are produced meaning more oxygen can be carried by the blood
- the body becomes more tolerant to lactic acid
