pressure within the cardiovascular system, the circulatory pressure is often divided into each of the following components except

during heavy exercise, if the heart rate were to exceed ca. 180 bpm, the pumping action of the heart would become inefficient, why?

beta blockers are drugs that reduce blood pressure. in the heart, they act as

which of the folllwing responses to a change in blood volume directly involved the heart

during the fight or flight response, sympathetic activity changes the distribution of blood as follows

each heartbeat begins with an action potential generated at a pacemaker called the

what mechanisms are responsible for movement of blood in the venous system of the lower limbs

the plateau phase of a cardiac action potential last for

cardiac output is an indication of blood flow through peripheral tissues and provides a useful indication of

blood is carried away from the heart by

how many muscular chambers does the heart contain

in contrast to skeletal muscle, cardiac muscle tissue contracts

the right atrioventricular (AV) valve is known as the

cardiodynamics is not dictated by which of the following factors

why is the left ventricle more muscular than the right ventricle

the right atrium passes blood to the right ventricle, which pumps blood into the

the conducting cells in the atria are found in

what molecular mechanism is responsible for the plateau phase of the action potential in cardiac muscle

the left atrium empties blood into the left ventricle, which pumps blood into the

blood flows through a network of blood vessels that extend from the ? to the peripheral tissues

what molecular mechanism prevents tetanic contraction of cardiac muscle

which structures ensure the rapid and accurate spread of excitation through cardiac muscle

why does increased rigidity of blood vessels (atherosclerosis) increase blood pressure

the wne systolic volume (ESV) is influenced by each of the following except

what would be the effect on the heart of the vagus nerve were cut

which of the following may increase blood viscosity

there are ? heart sounds

In the cardiac cycle a phase of contraction is known as

which of the following will increase the heart rate

what molecular mechanisms is responsible to the spontaneous generation of action potentials in cardiac muscle

electrical events of the conducting system can be monitored from the surface of the body by means of an

the P-R is the time from the start of ? to the start of the QRS complex and extension by even 0.2 sec can indicate damage to the conducting pathways or the atrioventricular (AV) node

what is the effect of neural inputs to the heart

which appears as the ventricles depolarise

? is calculated as the end diastolic volume (EDV, 135 ml) minus the ene systolic volume (ESV, 65 ml)

blood flow is determined by each of the following parameters except

which type of cells control and co ordinate heartbeat

the period between the start of one heartbeat and the start of the nest is called the

the reduced oxygen level at high altitudes will have which effect on cardiac activity

the Q-T interval indicates the time required for the ventricle to undergo a single cycle of depolarisation and repolarisation and extension may indicate all of the following

which chambers of the heart are directly connected? right atrium, right ventricle, left atrium or left ventricle

for circulation to occur the pressure gradient must be great enough to overcome the

an increased heart rate is primarily caused by which one of the following

blood from the systemic circuit flows through the venae cavae into the

at the end of the plateau phase potassium (K+) channels open leading to a rapid repolarisation that restores

an increased stroke volume is primarily caused by

the cardiac conduction system contains each of the following elements except

semilunar valves include

the action potential in a contractile cell is different than that observed in a skeletal muscle cell in that it has each of the following distinct steps except

which features of arteries act to reduce the fluctuations in blood pressure caused by the heart beat

systole is followed by ? during which the chamber fills with blood

each time the heart beats, a wave of depolarisation travels down the ventricular septum to the apex of the heart, from where it spreads through the ventricular

the heart has a series of ? valves

what May cause excessive turbulence in blood vessels

when the heart beats, the ventricles contract at the same time and the right ventricle ejects a ? amount of blood than the left ventricle

the electrical activity of the heart can be monitored by means of a graphical recording, which gives information on performance off each of the following specific components except

the arrival of an electrical impulse at a cardiac muscle cell membrane produces an ?, and this triggers the contraction of the cardiac muscle cells

an action potential begins when the membrane of ventricular muscle cell reaches threshold (-75 mV) from the resting potential of -90mV l, this results in opening of

capillaries are often called ? as their thin walls permit exchange of nutrients, dissolved gases and waste products between the blood and surrounding tissue

what is the bainbridge reflex