Tranport In humans Flashcards
What are the components of blood?
Red blood cells, white blood cells, platelets, plasma
Blood is a fluid tissue consisting of various cells suspended in a fluid.
What is the primary function of red blood cells?
Transport oxygen from the lungs to the rest of the body
This function is facilitated by haemoglobin.
What is haemoglobin?
A red pigment in red blood cells that combines reversibly with oxygen
It enables the transport of oxygen.
What shape do red blood cells have?
Circular, flattened biconcave disc
This shape increases the surface area-to-volume ratio.
Why is the absence of a nucleus in red blood cells significant?
It increases the capacity for haemoglobin and oxygen transport
More haemoglobin allows for more oxygen to be carried.
How do red blood cells adapt to flow through small blood vessels?
They can change into bell-shaped structures
This flexibility aids in navigating narrow passages.
Fill in the blank: Blood consists of red blood cells, white blood cells, platelets, and _______.
plasma
True or False: Red blood cells are rigid and cannot change shape.
False
Red blood cells are flexible and can change shape.
What color does oxyhaemoglobin appear?
Bright red
This is due to the combination of haemoglobin with oxygen.
What is the significance of the surface area-to-volume ratio in red blood cells?
It allows for faster absorption and release of oxygen
A higher ratio improves efficiency in oxygen transport.
What happens to oxygen levels in the lungs?
Oxygen level is high and oxygen diffuses from the alveoli into the blood.
What does oxygen bind to in red blood cells?
Oxygen binds to haemoglobin to form oxyhemoglobin.
What is the role of red blood cells in oxygen transport?
Red blood cells transport oxyhemoglobin to all the tissues of the body.
What occurs when blood passes through tissues with low oxygen?
Oxyhemoglobin releases its oxygen.
What is the process by which oxygen diffuses into tissue cells?
Oxygen diffuses into the tissue cells, allowing every cell in the body to receive its oxygen supply.
What role do white blood cells play in the body?
White blood cells fight diseases.
What are the two main types of white blood cells?
- Phagocytes
- Lymphocytes
What is phagocytosis?
The process where some white blood cells ingest foreign particles such as bacteria and digest them.
What do lymphocytes produce when pathogens enter the bloodstream?
Lymphocytes produce antibodies.
What do antibodies do to bacteria?
- Attach to the bacteria and cause the bacterial cell membrane to rupture
- Cause bacteria to agglutinate for phagocytosis
- Bind to and neutralise toxins produced by bacteria
What are blood platelets?
Fragments of cytoplasm that play a part in blood clotting.
What is the function of blood clotting?
Seals wounds to reduce excessive blood loss and prevents entry of foreign particles and infection.
What do platelets contain that aids in clotting?
Enzymes that aid the conversion of fibrinogen to insoluble fibrin threads.
What do fibrin threads do?
Entangle blood cells to form a clot or scab.
What is plasma?
A pale yellowish fluid composed mainly of water and various dissolved substances.
What is the function of plasma in the body?
Serves as a transport medium that delivers nutrients and transports waste products.
What substances are transported by blood?
Digested food, excretory products, hormones, oxygen
Substances include glucose, amino acids, mineral salts, fats, vitamins, nitrogenous waste, carbon dioxide, and more.
Where are digested food substances carried from and to?
From: Intestine
To: Other parts of the body
Excess mineral salts are transported to the kidneys for excretion.
What is tissue or organ transplant?
Replacement of badly damaged or diseased tissue or organ with a healthy one from a donor.
What can occur when transplanted tissue is rejected?
The recipient’s immune system may produce antibodies to destroy the transplanted organ.
When is tissue rejection not a problem?
When the transplanted tissue comes from the same person.
What is an example of a tissue transplant from the same person?
Replacement of burned skin using undamaged skin from another part of the person’s body.
What greatly reduces the risk of tissue rejection?
A tissue match, where the tissue to be transplanted is genetically similar to the recipient.
What are immunosuppressive drugs used for?
To inhibit or suppress the recipient’s immune system.
What are the risks of using immunosuppressive drugs?
Increased susceptibility to infections and lifelong use.
How is oxygen transported in the blood?
By haemoglobin in the red blood cells.
Where is oxygen carried from and to?
From: Lungs
To: All parts of the body for cellular respiration.
What is transported in solution in the plasma?
Food substances, excretory products, and hormones.
What is the human transport system called?
The circulatory system
It consists of the heart, different types of blood vessels, and blood.
What are the main components of the circulatory system?
Heart, blood vessels, blood
The system is responsible for transporting substances throughout the body.
What is the primary function of blood in the circulatory system?
Transporting oxygen and nutrients to all parts of the body and waste materials out of the body
This process is essential for maintaining homeostasis.
What is blood circulation?
The continuous flow of blood around the body in a closed system
This system ensures efficient transport of materials.
Name the main blood vessels that connect the heart, lungs, liver, and kidney.
Arteries, veins, capillaries
These vessels facilitate the transport of blood to and from these organs.
How do the structures of arteries, veins, and capillaries relate to their functions?
Arteries have thick walls for high pressure, veins have valves to prevent backflow, capillaries are thin for material exchange
Each type of vessel is specialized for its role in circulation.
Fill in the blank: The structure of _______ is adapted for efficient material transfer between blood and tissues.
capillaries
Capillaries allow for the exchange of gases, nutrients, and waste.
True or False: Blood only transports waste materials out of the body.
False
Blood also transports oxygen and nutrients to the body.
What is the role of capillaries in the circulatory system?
To facilitate the transfer of materials between blood and tissue fluid
This is crucial for nutrient delivery and waste removal.
What is the human transport system called?
The circulatory system
It consists of the heart, different types of blood vessels, and blood.
What are the main components of the circulatory system?
Heart, blood vessels, blood
The system is responsible for transporting substances throughout the body.
What is the primary function of blood in the circulatory system?
Transporting oxygen and nutrients to all parts of the body and waste materials out of the body
This process is essential for maintaining homeostasis.
What is blood circulation?
The continuous flow of blood around the body in a closed system
This system ensures efficient transport of materials.
Name the main blood vessels that connect the heart, lungs, liver, and kidney.
Arteries, veins, capillaries
These vessels facilitate the transport of blood to and from these organs.
How do the structures of arteries, veins, and capillaries relate to their functions?
Arteries have thick walls for high pressure, veins have valves to prevent backflow, capillaries are thin for material exchange
Each type of vessel is specialized for its role in circulation.
Fill in the blank: The structure of _______ is adapted for efficient material transfer between blood and tissues.
capillaries
Capillaries allow for the exchange of gases, nutrients, and waste.
True or False: Blood only transports waste materials out of the body.
False
Blood also transports oxygen and nutrients to the body.
What is the role of capillaries in the circulatory system?
To facilitate the transfer of materials between blood and tissue fluid
This is crucial for nutrient delivery and waste removal.
What do metabolic waste products diffuse into before entering the blood?
Tissue fluid
Metabolic waste products first diffuse from tissue cells into the tissue fluid.
What is the function of blood in relation to excretory waste products?
Transporting waste products to excretory organs for removal
Blood carries waste products from tissue to organs responsible for excretion.
Why is the rate of blood flow in capillaries slow?
To allow more time for the exchange of materials between blood and tissue cells
A slower blood flow increases the efficiency of material exchange.
What happens to red blood cells as they flow through blood capillaries?
They alter their shape
Red blood cells reduce their diameter and increase surface area.
How do red blood cells change their diameter when passing through capillaries?
Reduced diameter
This change allows them to easily pass through the capillary lumen.
What is the effect of increased surface area on red blood cells?
Speeds up absorption or release of oxygen
Increased surface area enhances gas exchange efficiency.
True or False: Arteries always carry oxygenated blood.
False
Not all arteries carry oxygenated blood; some carry deoxygenated blood, such as the pulmonary arteries.
What type of blood cells are involved in the immune response?
White blood cells
White blood cells play a crucial role in the body’s defense mechanisms.
What fluid surrounds tissue cells?
Tissue fluid
Tissue fluid is essential for nutrient and waste exchange between cells and blood.
What are the two main components transported by blood to tissue cells?
Oxygen and nutrients
Blood delivers essential substances to support cellular metabolism.
Where is the heart located in the body?
Between the lungs in the centre of the chest, tilted slightly to the left of the breastbone
How many chambers does the heart have?
Four chambers
What are the upper two chambers of the heart called?
Atria (singular: atrium)
How do the muscular walls of the atria compare to those of the ventricles?
Atria have thinner muscular walls than the ventricles
What are the lower two chambers of the heart called?
Ventricles
Why do ventricles have thick muscular walls?
To force blood out of the heart to other parts of the body
Which ventricle has a thicker wall and why?
The left ventricle; it must pump blood to the rest of the body, requiring high pressure
What does the right ventricle do?
Pumps blood to the lungs
What is the median septum?
A muscular wall that separates the right and left sides of the heart
What is the function of the median septum?
Prevents deoxygenated blood from mixing with oxygenated blood
What are the consequences of mixing deoxygenated and oxygenated blood?
Reduces the amount of oxygen carried to tissue cells
What does it mean if a patient has a hole in the median septum?
They are said to have a hole in the heart
What symptoms may patients with a hole in the heart experience?
Fatigue, shortness of breath, and in serious cases, heart failure
Fill in the blank: The thickness of the muscular layer of the heart chambers and blood vessels is related to the _______.
Pressure that they need to generate or withstand
What are the phases of the cardiac cycle?
Systole and diastole
What do valves in the heart prevent?
Backflow of blood
Valves ensure that blood flows only in one direction.
Name the types of valves found in the heart.
- Tricuspid valve
- Bicuspid valve
- Semi-lunar valves
Semi-lunar valves are located in the aorta and pulmonary vein.
What is the role of the upper and lower vena cavae?
Return deoxygenated blood to the right atrium
They collect blood from various parts of the body.
What happens when the muscles of the right atrium contract?
Blood flows into the right ventricle
The tricuspid valve opens when pressure conditions allow.
How many flaps does the tricuspid valve have?
Three flaps
The flaps are attached to the walls of the right ventricle by chordae tendineae.
What prevents the backflow of blood into the atrium when the right ventricle contracts?
Closure of the tricuspid valve
The chordae tendineae also prevent the flaps from reverting into the atrium.
What prevents backflow of blood from the pulmonary artery into the right ventricle?
Semi-lunar valves (pulmonary valve)
These valves close when the right ventricle contracts.
What is the pressure condition of blood in the pulmonary arteries compared to the aorta?
Lower pressure
This lower pressure reduces the rate of blood flow in the pulmonary arteries.
Fill in the blank: The flaps of the tricuspid valve point ______ to permit easy flow of blood.
Downwards
True or False: The blood in the pulmonary arteries is at a higher pressure than the blood in the aorta.
False
What is the purpose of the lower pressure in the pulmonary arteries?
Gaseous exchange in the lungs
It allows more time for oxygen and carbon dioxide exchange.
What does the contraction of the right ventricle force?
Closure of the tricuspid valve
This prevents backflow of blood into the right atrium.
What brings oxygenated blood from the lungs back to the left atrium?
Pulmonary veins
What happens when the muscles of the left atrium contract?
Blood pressure in the left atrium becomes higher than in the left ventricle
What valve opens to allow blood to enter the left ventricle?
Bicuspid valve
How is the bicuspid valve similar to the tricuspid valve?
Both are similar in structure and function, but the bicuspid has two flaps instead of three
What occurs when the muscles of the left ventricle contract?
Blood leaves through the aorta
What does the aorta distribute blood to?
All parts of the body, except the lungs
What prevents the backflow of blood into the left ventricle?
Aortic valve
What type of pressure does blood enter the aorta?
Very high pressure
What do the small coronary arteries branch from?
The aorta
What do the coronary arteries supply to the heart?
Oxygen and nutrients
What defines a heartbeat?
One ventricular systole and one ventricular diastole
What occurs during ventricular systole?
Contraction of muscles in both ventricles
What occurs during ventricular diastole?
Relaxation of muscles in both ventricles
What happens when the muscles in both atria contract?
A slight increase in atrial pressure forces blood into the relaxed ventricles
Fill in the blank: The _______ valve is similar to the tricuspid valve but has two flaps.
Bicuspid
True or False: The aorta has semi-lunar valves that prevent backflow of blood.
True
What are the phases of the cardiac cycle?
Atrial systole, ventricular systole, and diastole
What is the role of the semi-lunar valves during ventricular systole?
They are closed to prevent backflow
What occurs after a short pause in the cardiac cycle?
The muscles in the ventricles contract (ventricular systole)
This leads to increased pressure in the ventricles.
What sound is produced when the tricuspid and bicuspid valves close?
A loud ‘lub’ sound
This closure prevents backflow of blood into the atria.
What happens when the ventricular pressure exceeds the pressure in the aorta?
The semi-lunar valves in the aorta are forced open
This allows blood to flow out of the ventricles.
What is the source of blood for the right atrium?
The vena cavae
The left atrium receives blood from the pulmonary veins.
What occurs during ventricular diastole?
The muscles of the ventricles relax
This leads to a decrease in pressure in the ventricles.
What sound is produced when the semi-lunar valves close?
A softer ‘dub’ sound
This occurs during ventricular diastole.
What happens to the bicuspid and tricuspid valves during diastole?
They open
This allows blood to flow from the atria into the ventricles.
What is the sequence of events in the cardiac cycle?
Atrial systole, ventricular systole, diastole
Each phase involves specific muscular contractions and blood flow.
During which phase do the atrial muscles contract?
Atrial systole
This phase allows blood to flow from the atria to the ventricles.
What is produced after every ventricular contraction?
A pulse
Counting pulse beats per minute gives the heart rate.
What is the average normal heartbeat of an adult?
72 beats per minute
Heart rate varies with age and size.
True or False: Oxygenated blood flows through the right chambers of the heart.
False
Oxygenated blood flows through the left chambers.
Fill in the blank: The _____ valves close during ventricular systole.
bicuspid and tricuspid
This prevents backflow into the atria.
What happens to the ventricular pressure during the filling phase?
It gradually increases
This occurs as blood continues to enter the ventricles.
What type of blood flows through the left chambers of the heart?
Oxygenated blood
Deoxygenated blood flows through the right chambers.
What is blood pressure?
The pressure (force per unit area) that blood exerts on the walls of the blood vessels.
Blood pressure is a critical measurement in assessing cardiovascular health.
How is blood pressure typically measured?
From the arteries of the upper arm using the unit millimetres of mercury (mmHg).
This measurement is commonly taken using a sphygmomanometer.
When is blood pressure highest?
During ventricular systole when blood is forced into the arteries.
Ventricular systole is the contraction phase of the heart cycle.
When is blood pressure lowest?
During ventricular diastole.
Ventricular diastole is the relaxation phase of the heart cycle.
What are the non-pulmonary arteries?
Arteries excluding those that carry blood to and from the lungs.
These arteries are responsible for transporting oxygenated blood to the body.
How does blood pressure vary in the circulatory system?
It decreases from the aorta to the vena cavae.
Blood pressure is highest in the aorta and decreases through arteries, capillaries, and veins.
What generates blood pressure?
The contraction and relaxation of the left ventricle.
The left ventricle pumps oxygenated blood into the aorta, creating pressure.
Fill in the blank: Blood pressure is measured in _______.
millimetres of mercury (mmHg)
This unit reflects the height of a column of mercury that the pressure can support.
What does the graph illustrate?
Pressure changes in the left side of the heart during a cardiac cycle
What are the key components of blood pressure readings?
Systolic pressure and diastolic pressure
What is the normal systolic pressure range for an adult?
120-140 mmHg
What is the normal diastolic pressure range for an adult?
75-90 mmHg
What is considered a healthy blood pressure reading?
Lower than 120/80 mmHg
What blood pressure reading indicates high blood pressure or hypertension?
140/90 mmHg or higher
True or False: High blood pressure can occur temporarily after exercise.
True
What should be done if a person has persistent high blood pressure?
Requires medical attention
Fill in the blank: Blood pressure readings are expressed as a ratio of the _______ pressure over the diastolic pressure.
[systolic]
What generates the highest blood pressure when the heart is beating?
The aorta
What happens to the semi-lunar valves during ventricular systole?
They open
What happens to the bicuspid valve during ventricular systole?
It closes
What happens during ventricular diastole?
The bicuspid valve opens
What does the graph illustrate?
Pressure changes in the left side of the heart during a cardiac cycle
What are the key components of blood pressure readings?
Systolic pressure and diastolic pressure
What is the normal systolic pressure range for an adult?
120-140 mmHg
What is the normal diastolic pressure range for an adult?
75-90 mmHg
What is considered a healthy blood pressure reading?
Lower than 120/80 mmHg
What blood pressure reading indicates high blood pressure or hypertension?
140/90 mmHg or higher
True or False: High blood pressure can occur temporarily after exercise.
True
What should be done if a person has persistent high blood pressure?
Requires medical attention
Fill in the blank: Blood pressure readings are expressed as a ratio of the _______ pressure over the diastolic pressure.
[systolic]
What generates the highest blood pressure when the heart is beating?
The aorta
What happens to the semi-lunar valves during ventricular systole?
They open
What happens to the bicuspid valve during ventricular systole?
It closes
What happens during ventricular diastole?
The bicuspid valve opens
What is coronary heart disease?
A very common heart disease that causes a reduction of the blood supply to the heart muscles.
What are the two main coronary arteries responsible for?
Carrying blood and nutrients to the muscles of the heart.
What can result from a coronary occlusion?
A heart attack.
What happens to the heart muscle when it does not receive sufficient oxygen and nutrients?
The region of heart muscle dies.
What is the primary cause of coronary heart disease?
Atherosclerosis of the coronary arteries.
What occurs during atherosclerosis?
Fatty substances such as cholesterol and saturated fats are deposited onto the inner surface of the coronary arteries and form plaques over time.
How do fatty deposits affect the arteries?
They narrow the lumen of the arteries and increase the blood pressure flowing to the heart.
What happens to the inner surfaces of affected arteries in coronary heart disease?
They develop rough inner surfaces.
What is the risk associated with rough inner surfaces of arteries?
Increased risk of a blood clot forming or becoming trapped in the artery (thrombosis).
What occurs when the coronary arteries are completely blocked?
Blood and oxygen supply to the heart muscles may be cut off.
What can happen to heart muscles without oxygen?
They may be damaged, leading to a heart attack.
Fill in the blank: Coronary heart disease is caused by _______.
atherosclerosis of the coronary arteries.
True or False: A heart attack can result from reduced blood supply to the heart muscles.
True.
What type of diet increases the risk of high blood pressure and heart attack?
A diet rich in cholesterol and saturated animal fats
This diet can lead to various cardiovascular issues.
What should be substituted for animal fats to lower cholesterol levels?
Polyunsaturated plant fats
These fats do not stick to the inner surfaces of arteries.
What are the effects of smoking on heart disease?
Carbon monoxide and nicotine increase the risk of heart disease
Nicotine raises blood pressure and the risk of blood clotting.
What familial factors can increase the risk of coronary heart disease?
Family history of high blood pressure and high blood cholesterol
Genetics can play a significant role in cardiovascular health.
What lifestyle change can help strengthen the heart?
Engaging in regular exercise
Exercise maintains the elasticity of arterial walls.
How does age affect the risk of heart attack?
The risk of a heart attack increases with age
Aging is a significant risk factor for cardiovascular diseases.
What is the impact of a sedentary lifestyle on heart health?
Inactivity leads to the build-up of fatty deposits that block the arteries
A sedentary lifestyle is a major contributor to heart disease.
Fill in the blank: _______ can increase blood pressure and the risk of blood clotting in arteries.
Nicotine
True or False: A diet low in cholesterol and saturated fats can help prevent coronary heart disease.
True
