LO1 The Cardiovascular System Flashcards
(99 cards)
What is the blood made up of?
55% Plasma
4% White blood cells and platelets
41% Red blood cells
What are white blood cells also known as?
Leucocytes
Which molecules do plasma carry?
- Electrolytes
- Proteins
- Hormones
- Glucose
- Urea
- Vitamins and minerals
What is plasma good for?
- 90% of plasma is made up of water, making it good for transportation as other molecules can dissolve within it very easily
What are leucocytes (white blood cells) responsible for?
- they are responsible for identifying and fighting off infection that enters the body in the form of bacteria, viruses or fungi.
What are the 3 types of leucocytes (white blood cells)?
Neutrophils - ‘they are the ‘first response’ to infection. They recognise and engulf bacteria and fungi, then die and living only a few hours at a time. This process is called phagocytosis. Pus is made up of collections of dead neutrophils.
Monocytes - fight off bacteria, viruses and fungi, but last longer than neutrophils. They help to clear up dead cells from the bloodstream.
Lymphocytes - produce antibodies, fight viruses and destroy cancerous cells by producing ‘b-cells’ and ‘t-cells’
What is the structure of leucocytes (white blood cells)?
- Contain a nucleus
What is the function of erythrocytes (red blood cells)?
- filled with hemoglobin, used to transport oxygen and carbon dioxide from the lungs to all other tissues within the body
What is the structure of erythrocytes (red blood cells)?
- made inside bone marrow
- Biconcave shape
- no nucleus
- they have a large surface area to allow these gases to move in and out of the cell
- very flexible meaning they can move around narrow capillaries to deliver oxygen to body tissues
What are platelets?
- cell fragments that are responsible for travelling to and repairing damaged blood vessels (arteries, veins and capillaries)
- don’t have a nucleus
What is the function of platelets?
- they work alongside fibrinogen (a protein found in plasma) to deal damaged blood vessels
- the platelets detect a tear in the vessel wall and travel to the area. They react with the collagen in the torn vessel wall and become sticky. The fibrinogen fibers act as a mesh and pull the wound together forming a clot.
What is fibrinogen?
a protein found in plasma
What is the internal temperature of humans and mammals? Why does it need to be maintained?
- 37 degrees Celsius
- Needs to be maintained so the chemical functions within cells can work properly
What are the four functions of the blood?
- transporting and exchanging molecules
- temperature regulation
- prevents infections
- blood clotting
How does the blood transport and exchange molecules?
- blood is taken from the arteries to the capillaries to allow the exchange of substances
- when it reaches the capillaries, the high pressure causes pressure filtration which results in plasma passing through the capillary wall into covering all the cells in the body tissue.
What is the bloods function for regulating temperature
- The chemical reactions within cells generate heat so the blood disperses it and redistributes it round the body
How is blood tissue formed?
when the blood reaches the capillaries, the high pressure causes pressure filtration which results in plasma passing through the capillary wall into covering all the cells in the body tissue, which becomes blood tissue
What does the blood and blood vessels do when we are too hot?
- blood vessels widen
- blood gets sent to the skin surface so that heat can escape which is why we look red
What does the blood and blood vessels do when we are too cold?
- blood vessels constrict
- more blood is kept further within the body which is why we look pale
What is the bloods function for preventing infections?
- pathogens contain antigens which are recognised by neutrophils and lymphocytes, which will produce antibodies
- they target the pathogen and break it down so monocytes can attack them
- lymphocytes remember the code for making these antibodies so they can be used again
What is the bloods function for blood clotting?
- the vessel will constrict to slow down blood flow
- platelets gather at the site of injury, creating a plug to stop blood leaking, a process known as coagulation
- the tear in the vessel wall reacts with the platelets making them sticky
- fibrinogen forms a mash the traps the platelets and blood cells
- this then pulls the wound together to close the vessel wall
What is the pulmonary circulation?
the blood circulation to and from the lungs
RIGHT side of the heart
What is systematic circulation?
the blood circulation to and from the body
LEFT side of the heart
What does the circulatory system ensure?
The circulatory system ensures a continuous flow of blood to all cells - without this, cell death can occur which is why diseases of the cardiovascular system system have consequences for all body systems.