Blood And Circulation Flashcards
What is the circulatory system and what’s its purpose
It is the transport system in our bodies. Large organisms need transport systems to supply all their cells with food, oxygen, and other materials and remove waste from cells.
What are the 3 major components of the circulatory system?
Blood vessels, heart, blood
What is the fluid in our bodies called
Blood
What is the muscular pump in our bodies called
The heart
What is the network of tubes called in our bodies?
Blood vessels
What are the blood vessels
Veins, arteries, capillaries
What materials does the circulatory system carry around the body
• oxygen from the lungs to every cell in the body
• carbon dioxide from cells in body back to lungs
• waste (urea) from liver to kidney
• digested food, eg glucose, amino acids from small intestine to every cell in body
• heat from liver and muscles to every cell in body
• hormones to communicate between cells in the body
What is a simple way of the blood going from heart to lungs(extremely simple)
blood goes from the right side of the heart, to the lungs and then returns to the left side of the heart before it is pumped to the rest of the body. It then returns to the right side of the heart.
What is double circulation?
blood travels through the heart twice with each complete circuit of the body.(goes from heart to lungs to heart to rest of body)
What are the 4 steps of double circulation
- Blood enters the heart. It is deoxygenated.
- Blood is then pumped to the lungs to pick up some oxygen.
- Blood is now oxygenated and travels back to the heart.
- Blood is then pumped around the body so every cell gets its vital oxygen so that every cell can carry out the process of respiration
What is pulmonary circulation
The blood flowing through the right side of the heart and going to the lungs is called the pulmonary circulation
What is systemic circulation ?
The blood flowing through the left side of the heart and going round the rest of the body/s organs is called the systemic circulation.
Why are blood vessels important ?
Blood is carried in continuous tubes (our blood vessels) of different sizes to every part of the body and back again to the heart.
In each organ sugar and oxygen move into the cells and carbon dioxide moves back into the blood.
The direction of flow is kept up by the pumping of the heart.
Describe the arteries
Carry blood away from the heart.
Have strong thick muscular walls to withstand the high pressure as blood is pumped through them to all parts of the body.
Small lumen.
Thick layer of muscle and elastic fibres.
High pressure.
Describe the veins
To Carry blood back to the heart.
Do not have as thick walls (less muscle)as the blood pressure is much lower in them.(thin walls)
Have valves to help keep the blood flowing in one direction back to the heart.
Large lumen.
No pulse.
Flexible walls and squashed easily so blood pushed further along vessels.
Describe the capillaries
They allow substances to exchange at body cells e.g. food and oxygen.
Carry blood through organs + tissues.
Low pressure.
Have very thin walls to allow these substances to leak through.
Very tiny vessels with narrow lumen.
Single cell thick wall.
No pulse.
Delicate and easily broken.
What is the heart?
The heart is a 4 chambered muscular pump found just to the left of the sternum.
The wall of the heart is made from a special type of muscle called cardiac muscle. The cardiac muscle is supplied with blood via the coronary arteries.
What divides the 2 sides of the heart.? And what do we have to remember about diagrams of the heart?
The septum.
The heart has 2 sides - left and right.
In all diagrams the heart is shown as a mirror image - so the right is labelled on the left and vice versa
What does the septum do?
The 2 sides of the heart are divided by the septum - this prevents oxygenated and deoxygenated blood from mixing, improving efficiency
What are the upper chambers called and the lower chambers called?
The upper chamber is small and has thin walls — the atrium.
The lower chamber is larger and has thicker walls - the ventricle.
Tell me about the heart’s valves?
The heart has valves:
• One type of valve is found between the atria and ventricles
• These ensure the blood flows in one direction only
• There are also valves at the points where blood leaves the ventricles
• These stop blood flowing back into the heart between heart beats
• It is the closing of these valves that cause the heart sounds
Thickness of ventricles?
The left ventricle has the thickest wall as it has to generate enough pressure to pump the blood the greatest distance
The right ventricle wall is thinner as it only pumps blood to the lungs (these are close to the heart)
Plural of atrium
Atria
Atria walls?
Thin- they don’t have to pump blood any great distance
valve between the right atrium and ventricle name
tricuspid valve
valve between the left atrium and ventricle name
bicuspid valve
Summarise the events of a single heartbeat
The events of each heart beat are mirrored on the left and right sides.
• Blood enters the atria from a vein
• Blood is forced into the ventricles through the valves
• The ventricles then contract forcing the blood upwards
• Blood exits the heart via an artery
4 main components of blood
Red blood cells
White blood cells
• Platelets
• Plasma
Red blood cells facts/function
are very small and have no nucleus.
• are biconcave in shape, giving a large surface area: volume ratio
• contain an iron pigment called haemoglobin which can pick up oxygen.
• When oxygen combines with haemoglobin it forms oxyhemoglobin which is bright red.
When oxygen is released to the tissues it turns purple/red
• Have a life span of around 120 days
White blood cells facts/function
Are slightly larger than red blood cells come in many different types are concerned with protecting the body.
They are able to detect bacteria and then destroy them before they harm the body phagocytosis is when they engulf the bacteria to destroy them.
produce antibodies. These protect us from infection. They work by making the bacteria cells stick together so that it is easier to kill them and some others release toxins which neutralize the poison released by the bacteria.
Name some types of white blood cells
Lymphocyte
Monocyte
Eosinophil
Basophil
Neutrophil
Plasma facts/function
the liquid portion of the blood
• Yellowish in colour
Makes up around 55% of blood volume
• Is mainly water but…
• contains dissolved substances including:
• digested food (nutrients)
• Hormones
• Wastes like carbon dioxide
What % of our blood is plasma
55%
What % of our blood is red blood cells?
45%
What’s the buffy coat in our blood?
White blood cells and platelets- they make up less than one percent
Platelets facts/function
tiny cell fragments
carried around in the blood and usually do nothing
• if the blood is exposed to the air in a cut the platelets help to form a network of fibres at the cut, called a clot
• this prevents blood being lost from the cut and stops bacteria and dirt getting in
• the clot hardens to a scab. This keeps the wound clean while new skin grows.
What is the fatty deposit in our blood
Cholesterol
Finish this sentence…
The pulmonary artery is the only artery to carry
Deoxygenated blood.
(To the lungs from the heart)
Finish this sentence…
The pulmonary vein is the only vein to carry…
Oxygenated blood.
(From the lungs to the heart)
Why do arteries have a pulse but not veins and capillaries?
Pulse created by heart pumping and contraction of heart muscle
How to remember the side of the diagram of the heart with the tricuspid and bicuspid valves?
Left
A
Bicuspid
Right
A
Tricuspid
What does the heart do
Pumps oxygenated blood round the body. Transports blood around the body over 1000 times a day. Receives blood from the veins, pumps blood under high pressure into the arteries.
What do the valves in our heart do
The bicuspid and tricuspid valves prevent back flow .
(Atrio-ventricular valves)
Ventricles and their pressure
Left ventricular, high pressure, more muscle, pump greater distance.
Right ventricle thinner, lower pressure, only pumps blood to the lungs.
What are they types of white blood cells called
Lymphocytes and phagocytes
How many types of white blood cells are there
2
