Unit 1 : SAC 2 Flashcards
Function of the cardiovascular system
Transports oxygen, water and other nutrients t cells of the body
Transport wastes (CO2) away from the cells
Regulation of body temperature
Fighting disease
The heart
A muscular pump designed to circulate blood throughout the cardiovascular system
Left side of the heart
On the right side of the page
Has oxygenated blood to be delivered to the body
Right side of the heart
Has deoxygenated blood that travels to the lungs to remove carbon dioxide and gather more oxygen
Valves
The purpose is to ensure that the blood is only able to travel in one direction
Mitral valve
On the left side of the heart between the left atrium and the left ventricle
Keeps the blood in the left ventricle
Tricuspid valve
Is on the right side and is between the right atrium and right ventricle
Aortic valve
Between the aorta and the left ventricle and prevents the blood from going back into the left ventricle
Pulmonary valve
Between the right ventricle and the pulmonary artery to stop the blood from going back into the right ventricle
Order of the blood flow
Deoxygenated blood goes right atrium>right ventricle > pulmonary artery > Lungs > Left atrium > Left ventricle > Aorta which pumps oxygenated blood back to the body
Systole phase (pumping)
Is the contraction of the heart muscle forcing blood out of the ventricle and into the arteries
Diastole phase (filling)
Is the relaxation phase of the heart beat where the heart fills with blood from the veins
Stroke volume
Is the volume of the blood that is ejected from the left ventricle of the heat with each heart beat
80mL at rest, 120mL at maximal exercise
Heart rate
Is the amount of times per minute the heart beats
Cardiac output
Is the product of the two above terms. It is a measure of the volume of blood ejected from the left ventricle of the heart per minute
4.8L/min at rest, 20L/min at maximal exercise
Changes of heart rate during exercise
As exercise intensity increases the heart rate increase
Changes to stroke volume during exercise
As intensity increases from rest to submaximal intensity to maximal intensity stroke volume increases until it reaches its maximum volume at a submaximal intensity.
Cardiac output equation (Q)
Stroke volume x Heart rate
Blood vessels
The large network responsible for the transportation of blood around the body
Blood vessel types
Veins Venules Capillaries Arterioles Arteries
Arteries
Large thick blood vessels that carry large volumes of blood away from the heart
That blood is high pressure which is why the walls are so thick
Capillaries
Are tiny blood vessels that create a network between the arterioles and venules. they are the sites for gas exchange between the blood stream and the muscles
Veins
Are much less elastic as it has less pressure and contain pocket valves that prevent backflow of venous return. It returns the blood to the heart.
Arterioles
Are tiny branches of arteries that lead to capillaries
Venules
Venules are minute vessels that drain blood from capillaries and into veins
Precapillary sphinctre
Are bands of smooth muscle that surround each branch of the capillary at its exit from the arteriole.
Control the blood flow through the capillaries to redistribute blood for the parts of the body that need it most
Blood pressure
Is the pressure exerted by the arterial blood against vessel walls as it is forced through the cardiovascular system.
Systolic blood pressure
Is the pressure recorded during the contraction phase of the heart cycle (arteries)
Diastolic blood pressure
Is the pressure recorded during the relaxation phase of the heart cycle (veins)
Myoglobin
Is a molecule that is in muscle and is responsible for the uptake of oxygen as it moves from the capillaries and into the muscles
Oxygen binds itself to the myoglobin then is transported to the mitochondria
a-VO2 oxygen difference
Is a comparison of the concentration of oxygen in the arterial blood when compared to the concentration of oxygen in the venous blood
Red blood cell
Are formed in the bone marrow of long and flat bones
Contain haemoglobin which is responsible for the transportation of oxygen to the body’s muscles and tissues as well as the removal of CO2
Haemoglobin molecule
Is a protein molecule in red blood cells that oxygen binds to, allowing it to be carried from the lungs to the body’s tissues. It also carries CO2 from the tissues back to the lungs
White blood cells
Produced in bone marrow, lymph tissue and the spleen.
Help fight infections by attacking bacteria, viruses and germs that invade the body. They absorb and digest the organisms within the body that are disease causing
Platelets
Are formed in the bone marrow of long and flat bones
Are tiny blood cells that help the body form clots to stop bleeding. Platelets move to the site of damage and form a clot to repair the damage
Plasma
Is the liquid portion of the blood in which red/white blood cells are suspended
Maintains satisfactory blood pressure
Maintains blood volume
A site of exchange of vital minerals which are critical for cell function
Functions of blood
Transport if gases, fuels, minerals and antibodies
Important role in thermoregulation and avoiding dehydration
Pulmonary circuit
Venous (deoxygenated) blood returns from the body into the inferior vena cava
Enters right ventricle then up to right atrium where it is pumped through the pulmonary artery to the lungs
The oxygenated blood comes back through the pulmonary vein into the left atrium
then goes into the left ventricle before being pumped through the aorta to the body
Where should blood be sent?
The distribution of blood varies in response to where the blood is needed, how much and when it is needed.
Depends on the demand for oxygenated blood at that time
Distribution of blood during exercise
When we exercise the demand for oxygen increases and the flow increases to working muscles and decreases to non-essential organs
Vasodilation
Is the result of the precapillary sphincters relaxing surrounding the blood vessels.
It allows a greater deal of blood to flow through the vessel
Vasoconstriction
Is the result of the contraction in the precapillary sphincters surrounding the blood vessels
Allows a smaller volumes of blood to flow through the vessel
Homeostasis
Is the property of a system in which a variable is actively regulated to remain very nearly constant even when the external environment is changed
Negative feedback
Occurs when information is fed back in a manner that tends to reduce the fluctuations in the output
Thermoregulation
37 ^0 C
The hypothalamus detects a change from thermoreceptors and sends out signals to respond to the change and keep it stable
Thermoreceptors
Are nerves located in the skin that monitor the external temperature
They send impulses to the brain to make changes to keep body temperature stable
Acclimitisation
Living and training in hot conditions to expose the body to the stress of the heat and get the body used to it
Increases sweat rates, better at maintaining blood plasma
Funtion of respiratory system
Responsible for gas exchange within the body
Delivering air from the atmosphere to the lungs
Transfer oxygen to the bloodstream
Remove carbon dioxide from the blood
Oxygen uptake - system responsibility
Respiratory - Lung and airways take in oxygen
Cardiovascular - Heart, blood vessels and blood transport the oxygen
Muscular system - Muscles which take up and use the oxygen
Where does the oxygen go once inhaled
Into the lungs and down to the alveoli where is is exchanged with carbon dioxide into the capillaries, then to the heart into the arteries, arterioles and then the capillaries in working muscles
Oxygen delivery within the muscle
The oxygen in the capillaries (bloodstream) binds to a molecule called myoglobin which then transports it to the mitochondria
Aerobic energy production
Mitochondria uses the oxygen to breakdown fuels and create energy by resynthesizing ATP
Structure of the respiratory system
Nasal cavity Trachea Bronchi Bronchioles Alveoli Lungs Diaphragm
Inspiration
The movement of air from the external environment into the lungs
Expiration
The movement of air out of the lungs to the external environment
Lung capacity
Is the volume of air that can be held in the lungs after maximum inspiration
Vital capacity
Is the maximum amount if air that can be expired after a maximum inspiration
Residual volume
Is the amount if air left in the lungs at the end of a concious, maximal expiration
Tidal volume
Is the amount of air that is inspired per breath
0.5L per breath
Respiratory rate
Is the amount of breaths taken per minute
12-15 per min
Ventilation
Is the amount of air in L that is inspired and expired per minute
6-7.5 L/min
Ventilation formula
Ventilation = Tidal volume X Resiratory rate
Changes during exercise - respiratory rate
As the intensity of exercise the amount of breaths taken per minute increases
Changes during exercise - tidal volume
As intensity increases from rest to submaximal, tidal volume gradually increases but when we reach submaximal intensity there is a maximum volume of air that can be taken in
Changes during exercise - ventilation
As levels of intensity increase so do the levels of ventilation until maximum level is reached
Alveoli
Are microscopic air sacs connected to the airways that carry air in and out of them.
They are connected to capillaries to allow the gases to pass through them exchanging oxygen for carbon dioxide
Pulmonary diffusion
Explain the gaseous exchange that occurs in the lungs. The air in the alveoli moves from the higher concentration of oxygen to the lower concentration of oxygen in the capillaries across the thin membranes
Carbon dioxide exchange at the lungs
CO2 moves from an area of high concentration in the capillaries to an area of low concentration in the alveoli
Acute response to exercise - respiratory
Increased respiratory rate
Increased tidal volume
Increased ventialtion
Increased activation of alveoli
Acute response to exercise - cardiovascular
Increased heart rate
Increased stroke volume
Increased cardiac output
Redistribution of blood to muscles
Oxygen defecit
The period at the start of exercise where the oxygen supply is less than the demand. During this time energy is produced via the anaerobic pathways
Steady state
A period where the oxygen supply is able to meet the oxygen demand
EPOC - Excess post-exercise oxygen consumption
At the end of exercise where oxygen consumption remains above resting levels to assist in recovery
What will be different about an athletes cardiovascular system?
The ventricle will be thicker to pump more blood around the body
