Anatomy of the cardiovascular system Flashcards
At what vertebral level does the mediastinum split into the superior and inferior mediastinum?
T4
What is the endocardium mostly comprised of?
Simple squamous epithelium
What are valves made of?
Endocardium projecting into the lumen
When in the cardiac cycle does blood flow to the coronary arteries to feed the cardiac tissue?
Diastole
What are the main attachments of the heart?
Central tendon of the diaphragm
Sternum
Roots of great vessels
What secretes the pericardial fluid?
Serious pericardium
What are the three layers of blood vessels, and their main components?
Tunica intima - ep., BM and conn tissue
Tunica media - SM
Tunica adventitia - conn tissue
What are the three layers of the heart and their main components?
Endocardium - ep., BM and conn tissue
Myocardium - SM
Epicardium - conn tissue, BM and ep.
Which vessels act as pressure reservoirs?
Elastic arteries, as they can stretch and recoil overall pressure is maintained in the blood
What are the names of the two defined layers of elastic fibres found in muscular arteries?
Internal elastic lamina (IEL)- just under epithelium
External/outer elastic lamina (OEL)- between tunica media and tunica adventitia
Which vessels control flow by altering blood pressure?
Arterioles
What are capillary walls made up of?
ONLY tunica intima, endothelium on basement membrane
What are the three types of capillaries?
Continuous
Fenestrated - pores in endo., complete BL
Discontinuous
What types of capillaries are often found in muscles?
Continuous
What types of capillary are often found in kidneys and adrenal glands?
Fenestrated
What types of capillaries are found in the liver, spleen and bone marrow?
Discontinuous
What are sinusoids?
Large diameter discontinuous capillaries found where large amounts of exchange take place e.g. liver, some endocrine glands
What are the main differences between superficial and deep veins?
Superficial - thick walled - no surrounding support - drain into deep veins Deep - thin walled - surrounding support from deep fascia and muscles
What is the function of the lymphatic system?
Drains tissue fluid lost from the circulation back into the circulation via the subclavian veins
Describe the structure of lymphatic capillaries
Blind-ended
Lined by very thin endothelium
No fenestrations
Absent/rudimentary basal lamina
