Anatomy (Cardiovascular system)

Question 1

Parts and branches of the aorta

Accepted Answer

1. Parts and branches - ascending aorta: begins at the left ventricle --> only branches are coronary arteries - aortic arch: begins at the level of the sternal angle --> 3 branches - descending aorta: subdivided by the diaphragm into thoracic and abdominal parts --> many branches 2. Branches a) Aortic arch - brachiocephalic trunk, left common carotid artery, left subclavian artery b) Descending thoracic aorta - to the eosophagus, bronchi - eleven paired posterior intercostal arteries to the intercostal spaces c) Descending abdominal aorta i) Ventral branches (unpaired) - Coeliac trunk --> organs of the upper part of the abdominal cavity - Superior mesenteric artery --> small intestine and part of large intestine - Inferior mesenteric artery --> large intestine and rectum ii) Lateral branches (paired) - Inferior phrenic arteries --> Diaphragm - Renal arteries --> kidneys - Suprarenal arteries --> suprarenal glands - Gonadal arteries --> Ovaries/testes iii) Postero-lateral branches (paired) - Four pairs of lumbar arteries --> musculature of the posterior abdominal wall iv) Iliac arteries - at the level of L4 the aorta divides into two common iliac arteries --> division into internal (supply perineum, gluteal region, pelvic viscera) and external iliac arteries (supply the lower limb)

Question 2

Arterial supply to the limbs, head and neck

Accepted Answer

1. Upper limbs - Subclavian artery (first rib) --> axillary artery (axilla) --> brachial artery (teres major) - the profunda brachii artery branches from the brachial artery --> supplies the posterior arm - At the elbow the brachial artery divides into radial and ulnar artery --> form the deep and superficial palmar arches in the hand 2. Head and neck - Common carotid artery --> external and internal carotid artery - External carotid artery --> superficial temporal artery - Internal carotid artery passes to the cranial cavity to supply the brain and the eye - Subclavian artery --> vertebral arteries 3. Lower limb - External iliac artery --> Femoral artery --> Popliteal artery --> anterior and posterior tibial artery - Anterior tibial artery --> Dorsalis pedis artery - Posterior tibial artery and dorsalis pedis artery form the deep plantar arch

Question 3

Venous drainage of the limbs

Accepted Answer

1. Upper limbs - Superficial veins: Dorsal venous arch --> Cephalic (lateral) and basilic (medial) veins --> Median cubital arch --> Basilic vein joins with the brachial vein to form the axillary vein and the cephalic vein joins them further up to form the subclavian vein - The deep veins (radial, ulnar, brachial) accompany the arteries of the same name 2. Lower limb - Superficial veins: Dorsal venous arch --> great saphenous vein (medial) and small saphenous vein (lateral) --> small saphenous drains into the popliteal vein and great saphenous vein into the femoral vein - The deep veins (venae commtantes) accompany the arteries

Question 4

Venous drainage of the trunk, head and neck

Accepted Answer

1. Head, neck and brain - blood from the brain drains into the intracranial venous sinuses --> internal jugular veins --> subclavian veins 2. Thoracic cavity - Azygos system (azygos vein on the right and hemiazygos vein and accessory hemiazygos vein on the left) --> SVC 3. Abdominal cavity - Hepatic portal vein (from GI abdominal organs to liver) --> Sinusoids (wide capillaries in the liver) --> hepatic vein --> IVC - renal vein (drains kidneys) - Lumbar veins (ppsterior abdominal wall) - Gonadal veins --> right drains into IVC, left drains into left renal vein

Question 5

Subsystems of the systemic circulation

Accepted Answer

1. Circulation of the brain - anastomotic arterial circle - Two internal carotid arteries and two vertebral arteries (join to form the basilar artery) supply the brain and form an anastomotic circle (Circle of Willis) 2. Hepatic portal system - venous portal circulation: a portal circulation is one which blood vessels link two capillary networks (capillary circulation --> blood vessel --> capillary circulation) - venous blood from the capillary beds in the GI system --> hepatic portal vein --> capillary beds within the liver (sinusoids) --> hepatic veins --> IVC --> there are many small vessels between the portal and systemic venous circulation (porto-systemic anastomoses). In portal hypertension (restricted flow through the hepatic portal vein) the open up and the liver is bypassed

Question 6

Lymphatic system

Accepted Answer

1. Structure - fluid (plasma) leaves blood at the capillary bed and becomes tissue (interstitial) fluid --> returned to circulation via venous end of capillaries, but some excess tissue fluid passes into blind ending lymphatic capillaries --> lymphatic vessels --> thoracic duct/right lymphatic duct --> systemic circulation (venous angle) 2. Groups of lymphatic vessels - Deep lymphatic vessels: alongside deep vessels of the neck, limbs and trunk - Superficial lympahtic vessels: subcutaneous tissue - Lacteals (special lymphatic capillaries): absorb fat that has been absorbed from the small intestine 3. Lymph nodes - filtration of the lymph - arranged in groups that drain particular regions: Cervical, axillary and inguinal lymph nodes - superficial lymph nodes (neck, axilla, ingunal region) --> drain limbs and body wall - deep lymph nodes (around arteries) --> drain the viscera 4. Lymp circulation - lymphatic vessels carry lymph away from the lymph nodes to drain into one of two terminal vessels (right lymphatic duct/thoracic duct) --> venous system - lymph moves in one direction: towards the heart

Question 7

Structure and function of blood vessels

Accepted Answer

1. Types of arteries a) Elastic arteries (conducting vessels) - first and largest blood vessels - relatively thin walls, large amount of elastin --> recoil gives onward propulsion --> aorta and its 3 branches, pulmonary arteries, common iliac arteries b) Muscular arteries (distributing vessels) - medium sized - supply most of the body --> e.g. radial/ulnar artery, popliteal artery, inetrcostals c) Arterioles (Resistance vessels) d) Capillaries - form the capillary beds - permit two-way exchange between blood and tissue fluid 2. Veins - much thinner walls than arteries, greater lumen --> accomodate relatively large volumes of blood - large veins have valves that prevent backflow 3. Anastomoses and end arteries - anastomoses can equalise pressure differences and provide alternative routes for blood flow when an artery is obstructed (collateral circulation) - arteries with no anastomoses are know as end arteries

Anatomy (Fach) / Anatomy (Cardiovascular system) (Lektion)