2h Transport Flashcards
What are the main functions of the blood?
1) Transports oxygen and nutrients around the body eg. amino acids
2) Distributes heat energy around the body
3) Part of the immune system to defend against disease
4) To seal cuts to protect against infection
What are the 4 components of the blood?
red blood cells, white blood cells, platelets and plasma
What is plasma?
Plasma is the straw coloured liquid part of the blood which carries cells and dissolved substances and also helps distribute heat energy
What substances does plasma transports?
ATP
Oxygen
Water
CO2
Hormones
Platelets
Red blood cells
White blood cells
Waste eg. urea
Nutrients eg. amino acids and glucose
Where is food (glucose, amino acids) carried from and carried into the blood to?
Carried from villi (small intestine)
Carried in the blood to all parts of the body
Where is water carried from and carried into the blood to?
Carried from large intestine
Carried in the blood all around the body
Where is oxygen carried from and carried into the blood to?
Carried from the lungs (alveoli)
Carried in the blood all around the body
Where is carbon dioxide carried from and carried into the blood to?
Carried from all parts of the body
Carried in the blood to the lungs (alveoli)
Where is urea (waste) carried from and carried into the blood to?
Carried from the liver
Carried in the blood to the kidneys
Where is kidneys carried from and carried into the blood to?
Carried from the glands
Carried in the blood all around the body to the different target organs affected by the different organs
Where does blood plasma transport heat away from?
Blood plasma transports heat away from cells that are respiring rapidly, such as exercising muscle cells, and prevents then from overheating.
Where does blood plasma transport heat to?
Blood plasma transports heat to the environment by increasing the diameter of blood vessels in the skin where respiration takes place slowly
What is the core temperature?
The internal temperature of the body, about 37C, necessary for life processes to go on effectively
What percentage of plasma, white blood cells and red blood cells are in the body?
Plasma - 55%
Red Blood Cells - 45%
White Blood Cells - >1%
What are the adaptations of Red Blood Cells?
- A biconcave disc that is round and flat (increases their surface area)
- Contain hemoglobin, a molecule specially designed to hold oxygen and carry it to cells that need it
- They have no nucleus (more room for hemoglobin)
- Can change shape to an amazing extent, without breaking, as it squeezes single file through the capillaries
Where can more red blood cells be made?
In the bone marrow
What are white blood cells?
White blood cells are part of the immune system. Their role is to defend the body against disease. They respond to infection by attempting to kill the pathogen that has entered the body.
What are the groups of white blood cells?
There are different groups of white blood cells that each have a different role:
- Phagocytes
- Lymphocytes
- Memory Cells (a type of lymphocyte)
eg. HIV causes AIDS
Influenza causes the flu
Plasmodium causes malaria
Fungus causes Athlete’s foot
Salmonella causes food poisoning
What is a pathogen?
A disease causing microorganism
What is a phagocyte and what does it do?
Several types of white blood cells belong to this group, but they kill all pathogens by ingesting them. They engulf pathogens by flowing around them until they are completely enclosed, and then digest them. Different types of phagocytes target different pathogens such as bacteria, fungi and protoctist parasites
What are lymphocytes and what do they do?
This type of white blood cell has a very large nucleus and is responsible for producing chemicals called antibodies. When a pathogen infects the body, lymphocytes produce antibodies that specifically match that pathogen. the antibodies attach to the pathogen and either attract phagocytes to engulf the pathogen or cause the pathogen to break open and die
What are memory cells?
- Lymphocytes also make memory cells
- These cells remain in the blood long after the pathogen has been destroyed
- If the body is infected by the same pathogen again they recognise it and respond much faster an din higher quantities
How does immunisation (vaccination) work?
Immunisation provides natural immunity from a disease, without you being infected and becoming ill
Why can’t we produce a vaccination for the common cold?
Because the common cold mutates so there are different variations of the virus
What are platelets?
These clump together to form blood clots. This prevents excessive blood loss, and prevents pathogens from entering the wound. In a clot platelets are held together in a mesh of a protein called fibrin, other clotting factors are needed in the process
What is the circulatory system?
- The human circulatory system consists of the heart and blood vessels
- Delivers nutrients and oxygen to all cells in the body
What is the circulatory system’s function?
The circulatory system carries oxygen, nutrients, and hormones to cells and removes waste products like carbon dioxide
Oxygenated blood is carried away from the heart and towards organs and arteries
What is a double circulatory system?
Blood flows twice through the heart for every one time it flows through the body tissues
Where do arteries and veins go?
All Arteries go away from the heart
All Veins go towards the heart
Most arteries carry oxygenated blood
Most veins carry deoxygenated blood
What are the main arteries and veins?
- Aorta (main artery out of the heart)
- Vena Cava (main vein into the heart)
- Coronary Arteries (branch from the aorta into the heart)
- Coronary Vein (Vein into the right Atrium, from the heart)
- Hepatic artery and Hepatic vein (run into/out of the liver)
- Renal artery and vein (into/out of the kidneys)
- Pulmonary artery and vein (into/ out of the lungs)
- The carotid artery goes towards the head and brain and the jugular vein carries blood back to the heart
- Hepatic portal vein - between the digestive system and the liver
What is the direction of the heart flow? - from the left ventricle
Left ventricle -> semilunar valve -> aorta -> rest of the body (deoxygenated) -> vena cava -> Right Atrium -> Tricuspid Valve -> Right Ventricle -> Semilunar Valve -> Pulmonary Artery -> Lungs (oxygenates) -> Pulmonary vein -> Left atrium -> bicuspid valve -> left ventricle
What are valves?
Help prevent backflow of blood
What are capillaries?
Have walls that are only one cell thick, to allow for exchange of materials between blood and the cells
Why does an artery have a thick muscular wall?
Arteries have a thick muscular wall as there is a higher pressure inside the artery so it needs to be able to withstand pressure
Why do veins have valves?
Because there’s a lower pressure so blood is more likely to backflow
Why do veins have smaller muscles?
As there is lower pressure inside the veins so doesn’t need to deal with pressure
What structure has a thick muscular wall?
Artery
What structure has walls which are one cell thick?
Capillery
Which structure usually carries deoxygenated blood?
Veins
What structure contains valves?
Veins
What structure is found in the organs and tissue?
Capillary
What structure usually carries oxygenated blood?
Artery
Which structure’s blood is under very low pressure?
Veins
Which structure’s blood is under very high pressure?
Artery
Which structure’s blood is under pressure
Capillary - water and other substances are squeezed out into the surrounding intercellular spaces
Arteries
Thicker walls, smaller lumen, more elastic and more muscle fibres, no valves
Veins
Thinner walls, larger lumen, less elastic and less muscle fibres, valves to help blood return to the heart
Capillaries
Walls are one cell thick, they have no valves, food and oxygen pass out through the thin walls into the cells and waste and carbon dioxide enter the blood and are carried away
What is coronary heart disease?
- Build up of cholesterol in arteries which supply the heart with blood
- Reduces oxygen causes pain - angina
- Complete Blockage - Heart Attack
What factors can increase the risk of coronary heart disease?
- High cholesterol diet
- Old age
- Obese people
- Smoking
- Some genetic mutations
- lack of exercise
What factors can reduce the risk of coronary heart disease?
Exercise
What does heart rate mean?
The number of heartbeats per unit of time (usually per minute)
In what situations might your heart rate increase?
- When you exercise - your heart needs to beat faster so it can transport more oxygen and glucose to cells for respiration
- Being ill
- Adrenaline
What does the heart do alongside the heart rate increasing during exercise?
The heart also contracts more powerfully
What is the stroke volume?
The stroke volume is the volume of blood pumped in one heartbeat
