Transport In Animals Flashcards
What is an aneurysm
A localised bulge of an artery, vein or the heart wall. The wall of the blood vessel or organ is weakened and may rupture.
What’s an artery
Thick-walled vessel that carry blood away from the heart
What are arterioles
Smaller vessels divided from arteries that carry blood towards capillary beds.
What’s the atrioventricular node (AVN)
A small patch of tissue that passes electrical activity from the sinoatrial node down the bundle of His in the Purkyne tissue. Stimulates the ventricles to contract after imposing a slight delay to ensure atrial contraction is complete.
What are the atrioventricular valves
The valves between the atria and the ventricles.
What is the Bohr effect
The effect carbon dioxide has to increase the release of oxygen from haemoglobin
What is bradycardia
A slow heart rhythm of below 60 beats per minute.
What is the Bundle of His
Conducting tissue composed of Purkyne fibres that passes through the septum of the heart
What are capillaries
Very small blood vessels where water, solutes and respiratory gases are exchanged with body tissues.
What is the cardiac cycle
Sequence of events in one heartbeat including diastole and systole
What is closed circulation
A circulatory system where the blood is enclosed in blood vessels and does not come into direct contact with the cells of the body beyond the blood vessels.
What is diastole
The phase of the cardiac cycle when both the atria and the ventricles are relaxed.
What is double circulation
A type of blood circulatory system in which the blood flows through the heart twice for each full circuit of the body
What’s an ectopic heartbeat
An extra heartbeat or early contraction of the ventricles
What’s an electrocardiogram (ECG)
A technique for measuring tiny changes in the electrical conductivity of the skin that result from the electrical activity of the heart. This produces a trace, which can be used to analyse the health of the heart.
What’s fibrillation
Uncoordinated contraction of the atria and ventricles
What’s hydrostatic pressure
Pressure created by a fluid pushing against the sides of a vessel.
What’s HYPERtension
A condition in which the resting blood pressure (particularly the diastolic pressure) is raised for a prolonged period.
What is lymph
Excess tissue fluid that drains into a lymphatic or lymph vessel
What is mass flow
The movement of the fluid in one direction, usually through vessels
What is mass transport
The transport of molecules in bulk from one part of an organism to another
What is myocardial infarction
Heart attack. When coronary artery becomes blocked and part of the heart muscle is deprived of oxygen and dies.
What is meant by myogenic
A property of cardiac muscle which allows it to initiate its own contraction.
What is oncotic pressure
The tendency of water to move into the blood by osmosis as a result of the plasma proteins and other solutes. Also known as colloid osmotic pressure
What’s an open circulatory system
A circulatory system with a heart but few vessels to contain the transport medium
What is partial pressure
The relative pressure contributed by a gas to a mixture of gases
What is pulmonary circulation
The circulation of the blood through the lungs.
What is a pulse
As the heart pushes blood through the arteries, the arteries expand and recoil with flow of the blood.
What are purkyne fibres
Fibres that conduct the nerve impulse to the apex of the heart and up through ventricle walls.
What are semilunar valves
Valves at the base of the major arteries leaving the heart and in veins.
What’s a single circulatory system
A circulatory system where the blood flows through the heart and is pumped out to travel all around the body before returning to the heart.
What’s the sinoatrial node (SAN)
A small patch of tissue located at the top of the right atrium that generated electrical activity.
What’s systemic circulation
The circulation that carries blood around the body, excluding the circulation to the lungs.
What’s systole
The contraction of cardiac muscle.
What is tachycardia
An abnormally rapid OR fast heart rate, usually defined as greater than 100 beats per minute.
What are tendinous cords
String-like cords which attach the heart valves to the walls of the ventricles.
What is tissue fluid
Surrounds the cells of the body. It has a similar composition to blood plasma except it contains no large proteins or cells. Its function is to supply the cells with nutrients and remove waste products.
What are venules
A blood vessel that carries blood away from capillary beds towards veins
What are veins
A blood vessel that carries blood back to the heart
Which side of the heart pumps deoxygenated blood to the lungs
The right side
Which side of the heart pumps oxygenated blood round the body
The left side
Why does the atria have thin walls
Cause the receive blood returning to the heart (lower pressure)
Why do ventricles have thicker walls
Because they need to pump blood out of the heart and withstand higher pressures
Which blood vessel transports the blood from the lungs to the left atrium
Pulmonary vein
Which blood vessel transports blood from the left atrium to the body
Aorta
Which blood vessel allows deoxygenated blood from the body to enter the heart
Vena cava
Which blood vessel allows blood to travel from the right ventricle to the lungs
Pulmonary artery
What is the function of the valves in the heart and veins
To prevent blood flowing backwards
What side of the heart is the tricuspid valve
The right side
Which side of the heart is the bicuspid valve on
The left side
What’s the function of tendinous chords
Preventing atrioventricular valves turning inside out
What do the semilunar valves do
Connect the ventricles to the artery’s (pulmonary and aorta)
What’s the purpose of the septum of the heart
To prevent deoxygenated and oxygenated blood mixing
What’s the purpose of the coronary artery
Wraps around the heart supplying blood to cardiac muscle
Is a humans (mammals) heart open/closed and single/double
Closed, double
What does a ‘double circulatory system’ mean
The blood is pumped through the heart twice when it makes a full circuit of the body (ensures circulation isn’t too slow)
What are the advantages of a double circulatory system
Maintained conc gradient (deoxygenated and oxygenated blood don’t mix)
Blood pressure to lungs is slower (avoids damage, more time for gas exchange)
Blood pressure to body tissues is higher
What’s the purpose of the renal vein
Carries deoxygenated blood from kidneys to the vena cava
What’s the purpose of the renal artery
Carries oxygenated blood from the aorta to the kidneys
What is cardiac diastole
Atria and ventricles are relaxed (blood enters atria, pressure behind AV valves increases, AV valves open, blood enters ventricle)
What is atrial systole
Atria contract and ventricles remain relaxed (atria contracts to push blood into ventricles, SL remain closed)
What is ventricular systole
Atria relax and ventricles contract (AV valves close, SL valves open)
What makes the LUB sound
Ventricular valves closing (S1)
What makes the DUB sound
Semilunar valves close (S2)
What is meant when the heart is referred to as myogenic
The heart generates its own contraction
What part of the heart generates a wave of electrical stimulation (depolarisation)
The SAN (sino atrial node)
What happens after the SAN produces depolarisation
Depolarisation spreads through atria where they contract (can’t spread further due to a zone of non conductive tissue, annulus fibrosis)
Where does depolarisation travel after the atria
The atrioventricular nodes (AVN) passing onto the bundle of his
What does the depolarisation of the AVN cause
The contraction of the ventricle (bundle of his branches into purkinje fibres causing a delay allowing ventricles to fill with blood)
Calculating cardiac output CO= HR x SV
CO= the amount of blood ejected from the heart in one minute
HR= The number of heartbeats per minute
SV= amount of blood ejected by each heart beat
What’s an electrocardiogram
A device used to visualise the electrical activity in the heart
How do you preform an electrocardiogram
Electrodes attached to sticky labels placed on skins surface around the heart area
What can an electrocardiogram look for signs of
Changes in heart rate (bradycardia, tachycardia etc)
Rhythm (irregular, regular)
Length of cardiac cycle
Onset of a heart attack
What is blood made up of
Erythrocytes, leukocytes, platelets
What does plasma transport around the body
Heat transfer, digested food products, nutrient molecules, hormones, excretory products (CO2, urea)
What’s the function of erythrocytes
Transport of oxygen via haemoglobin, biconcave shape and no nucleus to fit through capillaries
What are the two groups of leucocytes
Granulocytes and agranulocytes
What are examples of granulocytes
Neutrophils (phagocytosis), basophils (histamine, inflammation), Eosinophils (parasites, inflammation, immunity)
What are examples of agranulocytes
Monocytes, lymphocytes
What’s the function of platelets
Fragments of megakaryocytes used in blood clotting
What is thrombosis
The process of forming a blood clot
What cascade of reactions results in a blood clot
Platelets attach to damaged collagen fibres
Thromboplastin is released from platelets
Thrombin catalyses the conversion of fibrinogen into fibrin
What is Atherosclerosis
The hardening of artery’s caused by the build up of plaque (atheroma)
What factors affect blood pressure
Age, diet, smoking, dehydration, exercise, stress, medication, disease
What do you use to measure blood pressure
A stethoscope (if done manually) and a sphygmomanometer
How do you carry out a measurement of blood pressure
Tie a blood pressure cuff around upper arm
Listen over brachial artery with stethoscope
Inflate cuff to 160-200mmHg
Slowly deflate cuff
Listen for first occurrence of rhythm sounds, the pressure when sound stops
