Anatomy of the Heart Flashcards
What is the blood vascular system?
A closed supply and drainage system ~ a continuous system
What are the four organs involved in the cardiovascular system and what are their roles?
Heart: the pump, pumps blood out
Arteries: supply, pipes that carry blood away from the heart and supply capillaries
Capillaries: exchange, brings nutrients to tissues and takes waste away
Veins/lymphatics: drainage, blood drained back towards heart
What is the lymphatic (vascular) system?
An open-entry drainage system ~ one way system
Plasma, fluid etc. can end up outside blood vessels in lymph
What is vascular tissue made up of?
Connective tissues: give strength and flexibility
Cells: epithelia (form barriers between environments) and muscle (cardiac muscle only found in heart, smooth muscle found in walls of blood vessels)
Pathway of blood in the heart
Deoxygenated blood travels from the right side of the heart to the lungs where it is reoxygenated and taken back to the heart through the left side where it is taken to capillaries
What do the lymphatic vessels do?
Lymphatic vessels drain back in a seperate pathway bringing fluid that has been lost and reuniting it with veins near the right side of the heart
Lymph nodes involved in immune surveillance
What are the pulmonary and systemic pathways?
Pulmonary pathway: deoxygenated blood from right side of heart to lungs where it becomes oxygenated and goes back to left side heart
Systemic pathway: oxygenated blood pumped from heart to everywhere else in body
What does the supply side of the heart consist of?
Arteries are the only supply path, they carry blood under high pressure
Major arteries are situated to avoid damage (deep in trunk, flexor aspect of limbs)
Important structures often receive supply from two arteries
Arteries change their name at each major branch
What does the exchange side of the heart consist of?
Capillaries of varying degrees of permeability
- Continuous (controlled ~ tight)
- Fenestrated (leaky)
- Sinusoidal (very leaky)
What does the drainage side of the heart consist of?
There are 3 pathways for drainage : deep veins, superficial veins and lymphatics
Veins carry low pressure blood hence if we damage superficial veins only need to apply light pressure to stop bleeding
Cross-sectional area of veins is at least twice of arteries so we can match supply and drainage pipes/shift same volume blood/second
What is the shape of the heart?
Blunt, cone shaped, size approx of a closed fist
Pointed end is inferior - apex - found between 5th and 6th ribs
Broad end is superior - base - found between 2nd and 3rd ribs
What does the right atrium receive?
Deoxygenated blood
Received from superior vena cava, inferior vena cava and coronary sinus
What does the left atrium receive?
Oxygenated blood
Received from four pulmonary veins
What are the layers of the heart wall?
Endocardium - within
Myocardium - muscle
Epicardium - upon/on top
Pericardium - around
What is the epicardium?
Outermost layer of the heart consisting of tubular structures (blood vessels)
Thicker where there are more blood vessels
Consists of a visceral pericardium (part of pericardium fused into epicardium), large blood vessels (arteries and veins) loose irregular FCT and adipose (fat)
