B2 W4 Flashcards
SVC
Superior vena cava comes from the common cardinal ceins
What joins the endocardial cushions to separate the ventricles?
Interventricular septum
Ventral aorta function
Ventral aorta joins the primitive heart tube and fuses to form the aortic sac.
Low pressure receptors
Stretch receptors in atria that cause blood pressure to fall. These are part of the natriuretic peptide system
Which arches disappear after pharyngeal arch 5?
Arch 1 and 2
Which pharyngeal aortic arches give rise to the vessels?
Pharyngeal arch 3, 4 and 6
What is the resistance to flow of liquid?
Viscosity
Which receptors are involved in short term control of BP?
Chemoreceptors/ Baroreceptors in the carotid artery and aortic arch.
What does the primitive ventricle give rise to?
Trabeculated (rough) R + L ventricles
What is the hormonal system for renal control of low blood pressure?
Renin-angiotensin-aldosterone
What gives rise to left subclavian artery?
Left 7th cervical intersegmental artery
What is the formation of new blood vessels?
Vasculogenesis. Angioblasts form islands and cords and canalisation occurs
Separate atria from ventricles during development
Atrioventricular endocardial cushions
Sinous venosus
Sinous venosus Gives rise to the smooth Right atrium, coronary sinus and oblique vein of LA
Where does the heart develop from?
Primary heart field
Primary heart field
Where heart develops from. Atria are laterally deposited and ventricular cells are medially deposited
What gives rise to the pulmonary artery?
6th pharyngeal arch
What is Pharyngeal arch 4?
Comes from the ventral aortic sac. Gives rise to aortic arch.
Which side does the heart loop towards during development?
Right side
Angioblastic cord
Angioblastic cords paired epithelial strands which canalise into the heart tubes.
What is the effect of prostaglandin?
Vasodilator which increases the GFR and reduce Na+ reabsorption
Increases blood pressure by acting as a potent vasoconstrictor and promotes aldosterone release
Angiotensin II
Which vessels are pressure reservoirs?
Arteries
Natriuretic peptide
Atrial natriuretic peptide Synthesised and stored by cardiomyocytes, released when BP is high to lower it
What gives rise to the external carotid artery
Pharyngeal arch 3
How are substances exchanged across capillary walls?
Diffusion, transcytosis and bulk flow
Bradykinin
Potent vasodilator broken down by ACE to increase BP
What are the metarteriole vascular shunts which control flow into the capillaries?
Precapillary sphincters
Angiogenesis
Angiogenesis Formation of new blood vessels from pre-exiting blood vessels by budding and branching. Occurs during wound healing.
Mechanorecepotrs that detect blood pressure
Baroreceptors
What is the consequence of Atrial septal defect?
Causes frequent respiratory infections, difficulty breathing and heart palpitations
Transcytosis
Transport where Substances in plasma are enclosed in pinocytic vesicles that enter endothelial cells by endocytosis and exit to the other side to other tissue by exocytosis
Aorticopulmonary septum
Spiral that allows blood to bypass the lungs and joins the pulmonary artery with aorta
Opening between atria which gets closed off by the descending septum primum
Foramen primum
Vasomotor center
Area in the medulla which regulates blood pressure via vasodilation
Which vessels have the highest cross sectional area?
Capillaries
Dorsal aorta
Dorsal aorta Which blood vessels which provides nutrient rich blood to the body tissues in the embryo.
Hemiangioblast
Hemiangioblast derived from mesoderm and ectoderm that produces blood cells
Stroke volume
Blood ejected from the left ventricle of the heart in one contraction, determined by end diastolic volume, end systolic volume and preload, contractility and after load.
Vasculogenesis
Formation of new blood vessels from angioblasts form islands and canals for canalisation
Aortic arch
Aortic sac, left aortic horn and left 4th arch artery
Bulbos cordus
Smooth Left and Right ventricles
-> includes conus arteriosus, outflow tract and infundibulum
Truncus arteriosus
Ascending aorta and pulmonary trunk
Primitive ventricle
Trabeculated L + R ventricle
Primitive atria
Rough L + R atria
Sinus venosus
Smooth R atria, coronary sinus and oblique vein of L atria
L+ R differentiation of the heart
Cardiac looping
Allows communication between the atria
Foramen secundum
Allows blood to bypass the lungs and joins the pulmonary artery and aorta
Aorticopulmonary septum
What regulates blood flow into tissues in response to demand?
Pre-capillary sphincters
Aldosterone release
Adrenal cortex via action of angiotensin II
ADH release
Posterior pituitary gland
What ensures blood flow around the body?
Pressure
Venous return is caused by…
Respiratory pump, muscular pump, gravity adn sympathetic venoconstriction
What carries blood from foetus to placenta?
Umbilical vein
Transcytosis
Substances in plasma are enclosed in pinocytic vesicles which enter via endocytosis into tissues and exit to the other side by exocyotosis
Preload
Volume in the heart pre-contraction, affected by venous returnwwhich affects blood end diastolic volume
Endocardium
Inner lining of the heart formed of simple squamous epithelia
