Body systems for circulation and immunity (SAC 3) Flashcards
Cardi/o-
Heart
Coron/o-
Heart
CV system-components
Heart
Blood vessels
Systemic circulation
Moves blood between the heart and tissues/organs of the body and back to the heart
Removes waste from tissues back to the heart via diff
Pulmonary circulation
Moves blood from heart to lungs and back to heart
Moves CO2 from heart to the lungs via diff
Angi/o-
Vessel
Aort/o-
Aorta
Ateri/o-
Artery
Arteriol/o-
Arteriole
Phleb/o-
Vein
Ven/o-
Vein
Venul/o-
Venule
-stenosis
Narrowing
-sclerosis
Hardening
Arteries-S and F
S- thick, muscular wall and small lumen
F- carry blood at a high pressure, carry blood away from the heart at a rapid rate, oxygenated blood except for pulmonary artery
Arterioles-S and F
S- branch of arteries (smaller) and further from heart
F-direct oxygenated blood from artery to capillary
Capillaries-S and F
S-single layer of smooth muscle cells (easy gaseous exchange)
F-diffusion of nutrients and waste between blood and tissue
Number of capillaries depend on the function of the tissue and individual’s fitness e.g. athlete has more
Venules-S and F
S- capillaries converge into venules which then converge into veins
F-direct deoxygenated blood from capillary to vein
Veins-S and F
S-thin, floppy walls and large lumen
F-carry deoxygenated blood back to the heart (except pulmonary vein), slow and even blood flow, low pressure
Contain one way valve-allow blood to go in one direction and prevent back flow
The Heart-structure
- 4 chambers=2 atria and 2 ventricles
- thoracic cavity
- ventral
Layers of the heart wall
- pericardium (outermost layer)= a fibrous sac that encapsulates the heart
- myocardium (middle layer)= comprised of cardiac muscle, involuntary muscle and transmits electrical stimuli
- endocardium (innermost layer)= lines the chambers and valves of the heart
Atria
- upper chambers
- receive blood= deoxygenated from body to RV and oxygenated from lungs to LV
Ventricles
- lower chambers
- expel/pump blood out= deoxygenated through PA to lungs and oxygenated through aorta to body
Aorta-S and F
S-big artery from LV to body
F- carry oxygenated blood from the left ventricle to the body
Superior and inferior vena cavas-S and F
S-biggest veins and empty blood into RA
F-empty deoxygenated blood into the heart RA from structures above/below diaphragm
Pulmonary artery-S and F
S- away from RV to lungs
F- carries deoxygenated blood from heart to lungs
Pulmonary vein-S and F
S-from lungs to LA
F-carries oxygenated blood from lungs to heart
Septum-S and F
S-muscular wall b/w L and R side
F-seperate L and R side of heart
Bicuspid valve-S and F
S-2 and L side
F-prevent regurgitation of blood back into L atrium
Tricuspid valve-S and F
S-3 and R side
F-prevents regurgitation of blood back into R atrium
Semilunar valves-S and F
S-aortic and pulmonary valves
F-prevent reflux of blood back into ventricles
Chordae tendinae-S and F
S-thick, strong fibrous chords that connect leaflets of the bicuspid and tricuspid valves to the papillary muscle
F-help regulate the opening and closing of valves
Blood supply
L and R coronary blood vessels branch from the aorta and surround and supply the heart
Myocardial infarction
Reduced blood flow in coronary artery b/c:
-atherosclerosis
-occlusion= embolus (blocked BV e.g. from plaque) and thrombus (blood clot)
Irreversible damage b/c ischaemia or hypoxia
Sympathetic nervous system
Increased firing of SA node that increases HR
Parasympathetic nervous system
Decreased firing of the SA node that decreases HR
Cardiac conduction system
- SA node
- AV node
- Bundle of His
- Bundle branch
- Purkinje fibres
SA node-S,L and F
S- collection of specialised/ pacemaker cells
L- upper wall of R atrium
F- generate electrical impulses that trigger atrial contraction
AV node-S,L and F
S- small mass of neuromuscular tissue
L- wall of atrial septum and near tri valve
F- transmit electrical signals from the atria to the ventricles and ensure the atria are fully empty before the ventricle contracts
Bundle of His-S,L and F
S-mass of fibres from the AV node
L-upper end of ventricular septum
F- transmits electrical impulses from the AV node to the Purkinjefibres to create a ventricular contraction
Purkinje fibres-S,L and F
S-specialised conductive cells
L- myocardium of ventricular walls
F- ventricular contraction
Cardiac output
SV x HR
The volume of blood ejected from each ventricle every min
Stroke volume
The volume of blood expelled by each contraction of the ventricles
Heart rate
Number of times the heart beats per min
Atrial systole
Contraction of the atria
Ventricular systole
Contraction of the ventricles
Diastole
Relaxation of both the atria and ventricles (blood flows into heart)
Tachycardia
Abnormal condition of fast heart rate
Bradycardia
Abnormal condition of slow heart rate
Vital signs
- body temp
- pulse rate
- resp rate
- blood pressure
Pulse rate
Number of times the heart beats per min
Pulse
Bulge of an artery from waves of blood passing through the vessel each time the heart beats
Superficial arteries
- carotid=neck
- radial=wrist
- femoral=upper leg
- popliteal=back of knee
- dorsal/pedal=foot
Pulse-strength
Force of the pulse (amount of blood forced into artery)
- bounding=large amount of blood and strong pulse-caused by exercise, anxiety and alcohol consumption
- weak=small amount of blood and weak pulse=weak, feeble, thready
- strong=less than bounding but stronger than normal-shock and haemorrhage
Pulse-rhythm
Evenness of beats (time between beats)
- irregular= not have an even pattern-vary time between beats and strength
- intermittent=strength does not vary greatly but a beat is skipped (regular or irregular intervals)
Pulse oximeter
- gives readings of HR and SpO2
- light through tissue-measure the amount of light absorbed by oxygen carrying haemoglobin
