The structure and function of the heart

Question 1

Name the Blood vesssels involved in a heart

Answer 1

Pulmonary Artery
Pulmonary Vein
Aorta
Vena Cava
Left and Right Atrium
Left and Right Ventricle
2 Valves

Question 2

How to Calculate Cardiac Output

Answer 2

Heart Rate X Stroke Volume

Question 3

Describe Diastole

Answer 3

blood returning to the atria
flows into the ventricles.
the higher pressure in the arteries closes the SL valves

Question 4

Describe atrial systole

Answer 4

transfers the remainder of the blood through
the atrio-ventricular (AV) valves to the
ventricles.

Question 5

Describe Ventricular Systole

Answer 5

closes the AV valves and pumps the blood out through the semi lunar (SL) valves to the aorta and pulmonary artery

Question 6

What is responsible for the heart sounds heard with a stethoscope

Answer 6

The opening and closing of the AV and SL valves

Question 7

What sets the heart contraction rate

Answer 7

The auto-rhythmic cells of the sino-atrial
node (SAN) or pacemaker, located in the wall
of the right atrium, set the rate at which the
heart contracts.

Question 8

Describe The structure and function of the cardiac
conducting system

Answer 8

1. The heartbeat originates in the heart itself.

2.The auto-rhythmic cells of the sino-atrial
node (SAN) or pacemaker, located in the wall
of the right atrium, set the rate at which the
heart contracts.

3.The timing of cardiac muscle cell contraction
is controlled by impulses from the SAN
spreading through the atria causing atrial
systole.

4.They then travel to the atrioventricular node (AVN), located in the centre
of the heart.

5.Impulses from the AVN travel down fibres in the central wall of the heart and then up through the walls of the
ventricles, causing ventricular systole.

Question 9

What is the sympathetic nerve

Answer 9

releases noradrenaline
which increases the heart rate,

Question 10

What is the Parasympathetic nerver

Answer 10

releases
acetylcholine which decreases the heart rate.

Question 11

What regulates the rate of the sinoatrial node

Answer 11

The Medulla

Question 12

What does the Medulla do

Answer 12

regulates the rate of the sinoatrial node through the antagonistic action of
the autonomic nervous system (ANS).

Question 13

When does blood pressure increase and decrease

Answer 13

Blood pressure increases during ventricular
systole and decreases during diastole.

Question 14

Describe a sphygmomanometer

Answer 14

1. An inflatable cuff stops blood flow, in the
   artery, and deflates gradually.

2.The blood starts to flow (detected by a pulse) at systolic
pressure.

3.The blood flows freely through the artery (and a pulse is not detected) at
diastolic pressure.

Question 15

What is a huge risk factor for coronary heart disease

Answer 15

Hypertension