Help Me Term 2 Crash Part 2 Flashcards
The trachea develops from which of the following?
A) intermediate mesoderm
B) neural tube ectoderm
C) splanchnic mesoderm
D) foregut endoderm
E) somatic mesoderm
Foregut endoderm
What does the splanchnic mesoderm develop into?
Visceral pleura
Gas exchange starts to occur at which stage of lung development?
Saccular stage
The central tendon of the diaphragm develops from which of the following?
A) pleuropericardial fold
B) oesophagotracheal septum
C) septum transversum
D) pleuroperitoneal fold
E) pericardioperitoneal canal
Septum transversum
Parietal pleura develops from what?
Somatic mesoderm
4 separate structures of the respiratory system?
1) trachea
2) lungs
3) pleura
4) diaphragm
What’s the first thing that happens when the resp system is being developed? (2)
Somatic/parietal mesoderm folds to surround the splanchnic/visceral mesoderm
Yolk sacs absorbed into primitive gut
What does the initial folding of the embryo give rise to?
The primitive gut tube
What’s the foregut a component of
The primitive gut tube
The gut tube formed from what
The endoderm
The endoderm can be spilt into what 3 sections
Foregut
Midgut
Hindgut
What happens (resp related) to embryo at 4 weeks?
Trachea and lung bud out from primitive foregut (of the endoderm)
After the trachea and Lung buds (off the endoderm) are formed, what happens?
The trachea and lung buds are closely surrounded by lateral plate splanchnic (visceral) mesoderm
So like endoderm surrounded by mesoderm,
But like it’s the trachea surrounded by the lateral plate splanchnic
So now that the trachea and lung buds have come out the foregut at 4 weeks, what happens?
Septum develops between oesophagus and trachea, completely separating them
(Trachea and oesophagus don’t separate)
Fistula And Atresia
Fistula = abnormal passage, cuz they haven’t separated
Therefore
Atresia = dead end
Cuz the first half of the passage is attached/ hasn’t separated, so the other end is a dead end
How does the pleura develop?
1) lung bud was originally in the coelemic cavity, and grows to fill it out
2) lung is then covered in visceral pleura
3) thoracic wall is lined with parietal pleura
4) therefore coelemic cavity is reduced due to the growth of the lung… to become the pleural cavity
Where does the pleura develop from?
The lateral plate mesoderm
How does the pleura develop, in terms of the mesoderm?
Buds will push the splanchnic mesoderm towards the somatic mesoderm and be surrounded by both layers
Space = pleural cavity
Splanchnic layer of the lateral plate mesoderm = what pleura
Visceral pleura
Somatic layer of the lateral plate mesoderm = what
Parietal pleura
The pleural cavity is initially continuous with the pericardial and peritoneal cavity. What is this continuity called
The pericardioperitoneal canal
Why does the pericardioperitoneal canal need to be sealed off
So that the pleural cavity is a closed space, for correct ventilators pleural cavity pressure
How is the pericardioperitoneal canal sealed off
The formation of pleuropericardial folds, which are then lined by somatic mesoderm
What seals off the pleural cavity from the pericardial cavity
pleuropericardial folds,
When does gas exchange begin?
The saccular stage (27-40 weeks)
When there is the formation of alveolar sacs, primitive alveoli, and surfactanr
What gives the glassy appearance in respiratory distress syndrome
Debris of blood elements accumulate
Cuz remember it’s caused by surfactant deficiency, so there is partial collapse of alveoli, and therefore blood elements accumulate
What’s lung agenesis
Failure of lung bud to develop- maybe due to insufficient mesoderm
What’s pulmonary hypoplasia
Incomplete development of the lungs, so abnormally low number or size of bronchi pulmonary segments or alveoli
What closes off the pleural cavities from the peritoneal cavity of the abdomen?
Pleuroperitoneal folds/membranes forming the diaphragm
The diaphragm develops from what 4 mesodermal structures
Septum transversum
Pleuroperitoneal folds
Skeletal muscle from peripheral body wall
Dorsal mesentry of the oesophagus
Diaphragm from what
Mesoderm
What does the septal transversum form?
The central tendon of the diaphragm
The pleuroperitoneal folds- how is this involved with formation of the diaphragm?
(They’re somatic mesodermal)
fuse with the septum transversum to close off the pleuroperitoneal canals, to separate the pleural cavities from the peritoneal cavity
The pleuropericardial folds fuse with the septum transversum. Failure for this to happen results in what
Herniation of abdominal contents, into the thorax
The pleuropericardial folds carry what nerves
The lower intercostal nerves to supply the periphery of the diaphragm
Skeletal muscle ingrowth does what in the formation of the diaphragm
Grow inwards to cover the pleuropericardial folds and form the muscular part of the diaphragm
What nerve for muscular part of the diaphragm (that grows inwards to cover the pleuropericardial folds)
Phrenic nerve
The dorsal mesentery of the oesophagus: what does this do in the formation of the diaphragm (2)
The dorsal mesentery of the oesophagus attaches the embryo logical oesophagus to the posterior thoracic wall.
Skeletal muscle from the periphery covers the dorsal mesentery to form the diaphragmatic crura
How is the diaphragmatic crura formed?
Skeletal muscle from the periphery covers the dorsal mesentery, to form the diaphragmatic crura
Weak areas in developed diaphragm could lead to abnormalities. What about the oesophageal hiatus?
Could lead to a hiatus hernia
What could happen if the diaphragm doesn’t completely close during development?
Protrusion of an organ through the muscle/ structure that usually contains it
Eg small intestine, pushing lungs and heart to the right, leading to pulmonary hypoplasia
Hiatus hernia might =
Small intestine, pushing lungs and heart to the right, leading to what
pulmonary hypoplasia
What’s the sympathetic innervation of the lung?
T1-4/5 of spinal cord, via rani communicates, to reach sympathetic trunk, where they synapse in the upper thoracic chain
Which nerves constrict the bronchial smooth muscle?
Parasympathetic nervous system
Stimulation of the cholinergic nerves cause bronchoconstriction, mucus secretion, bronchial vasodilation
i believe that’s vagus but i’m not sure
Where does the trachea receive sensory innervation from?
Recurrent laryngeal nerve
Venous drainage of trachea? (3)
Brachiocephalic
Azygous
Accessory hemiazygous
Where does the bronchi get its innervation from?
Pulmonary branches of the vagus nerve
Bronchial arteries
Bronchial veins
The bronchi = innervation from Vagus
The trachea = innervation from recurrent laryngeal.
Where does the recurrent laryngeal come from?
It’s a branch off the vagus
What’s the innervation of the parietal and visceral pleura?
Parietal = intercostal and phrenic
Intercostal nerves provide innervation to costal pleura and peripheral diaphragmatic pleura
Visceral = pulmonary plexus- network of nerves from both the sympathetic trunk and the vagus nerve
What’s the visceral pleura innervated by?
Pulmonary plexus
(a network of nerves derived from the sympathetic trunk, and vagus nerve).
Where does the breast drain
Axillary, parasternak, abdominal lymph nodes
What are intercostal muscles innervated by?
Ventral rami of the thoracic spinal nerve
What nerve innervates the visceral pleura of the lung? Vs parietal pleura?
Visceral = vagus nerve
Parietal = phrenic nerve
In addition to the pulmonary and systemic circulations, what two other sub/micro circulations are there? (One blood, one not)
Hepatic portal circulation
Lymphatic system
The mediastinum is divided into a superior and inferior mediastinum. What’s the inferior mediastinum subdivided into?
Inferior mediastinum into anterior, middle, and posterior.
Which organs are contained in the mediastinum?
All the thoracic organs except the lungs
The pericardium is attached to what bony structure?
The sternum
What is the heart attached to inferiorly?
The central tendon of the diaphragm.
Which costal cartilages are anatomically ‘related’ to the heart?
Costal cartilages 4-7
Posterior anatomical relations of the heart?
Oesophagus and descending aorta
Lateral anatomical relations to the heart? (Hint: think big AND small (2) )
Pleura
Phrenic nerves
How many border has the heart got
4
How many surfaces has the heart got?
3
The heart lies anterior to which vertebrae?
T5-T8
(Middle 4) but like, just remember t5-8
The heart lies inferior to which costal cartilages?
(The sternum) and
Costal cartilages 4-7
The apex of the heart is formed by what part of the heart
The left ventricle
The apex of the heart is at which intercostal space?
5th in the midclavicular line
Right border is mainly from what part of the heart
Right atrium
Left border is made of what part of the heart?
Left ventricle
Superior border is made of what part of the heart?
Auricles and great vessels
Inferior border of the heart is made up of which part of the heart?
Right atrium, right ventricle, left ventricle
What’s the anterior/sternocostal surface made up of?
1/3 right atrium
2/3 right ventricle, and left ventricle
Inferior (diaphragmatic) surface = what
Right ventricle and left ventricle
Posterior surface (base) of the heart is made up of what?
Left atrium (base)
Upper left of the heart (surface anatomy ONLY) reaches which rib?
Second rib
Surface anatomy of the heart only, right side reaches which rib?
3rd
To 6th
How many pericardia are there?
Fibrous and serous
What’s the fibrous pericardia
Dense connective tissue sac
What’s the serous pericardium split into?
Outer parietal layer
Inner visceral layer
Where’s the pericardial cavity?
Between the parietal and visceral layer, and it’s filled with fluid
So that’s the serous pericardium
What’s the epicardium?
It’s the innermost layer of the serous pericardia
It’s the inner visceral layer
There are two layers of the serous pericardia : parietal and visceral. Are they separate?
No
Continuous
Like a ballooooooooon
Deep to superficial, explain the surface of the heart:
Endo
Myo
Epi (visceral peri/serous)
Pericardial cavity
Pari peri (serous)
Fibrous peri
What’s see to the epicardium? (2)
The endocardium AND the myocardium
What’s the serous pericardial surface of the heart- which is superficial to the endocardium, and the myocardium?
Epicardium (visceral)
Cavity
Parietal pleura
What’s superficial to the serous pericardia?
The fibrous pericardia
Purpose of fluid in pericardial cavity
To prevent friction
Is the epicardium part of the heart?
Yes, the visceral layer…. Most external layer
Vat do coronary arteries do?
Supply blood to the heart muscle
Two main coronary arteries?
R and l coronary artery
What does the right coronary artery divide into?
Right posterior descending artery (goes around the back)
Acute marginal artery (small part at the front)
Right posterior descending artery (goes around the back)
Acute marginal artery (small part at the front)
These are all from the right coronary artery. What part of the heart is supplied?
Right atrium
Right ventricle
and da nodes
What does the left coronary artery divide into?
Left anterior descending artery
Circumflex artery
Left coronary artery > Left anterior descending artery
Circumflex artery
Supply blood to where?
Left atrium and left ventricle
Coronary veins bring deoxygenated blood back to where
Right atrium
Deox blood goes back to right atrium via what
Coronary sinus
Unless anterior vein which goes direct to RA
What branches off the coronary sinus? (4)
Small cardiac vein, from RA and RV
Middle vein from RV
Posterior vein from LV
Great cardiac vein (comes from front of the heart) from RV, LV, and LA
What coronary vein exists that doesn’t come off the coronary sinus?
Anterior vein
Goes directly to right atrium
Where does the small cardiac vein drain?
Right atrium
Right ventricle
Where does the middle cardiac vein drain?
Right ventricle
Where does the posterior cardiac vein drain?
Drains LV
What does the great cardiac vein drain?
R and L V, and LA
What does the anterior vein drain?
A small portion of the anterior surface of the right ventricle
Name the two major solcus
Coronary (atrioventricular) sulcus
Interventricular sulcus
Where does the coronary (atrioventricular) sulcus lie?
Between atria and ventricles
Where does the inter ventricular sulcus lie?
Between right and left ventricles
What’s an anastomosis?
A Junction of vessels
Where does the right coronary artery arise from?
The right aortic sinus of ascending aorta
Where does the right coronary artery give off the right marginal artery?
At inferior margin of the heart
On which surface of the heart does the right coronary artery give off the posterior descending artery?
Posterior surface of the heart
Which sulcus does the right coronary artery run?
Coronary/atrioventricular sulcus
Where does the left coronary artery arise from?
From left aortic sinus of the ascending aorta
In which sulcus does the left coronary artery run?
Coronary sulcus
The left coronary artery divides almost immediately into which branches?
Left anterior descending artery
Circumflex artery
The left anterior descending artery (which is a branch off the left coronary artery- which is in the coronary sulcus) runs in which sulcus?
Inter-ventricular sulcus
What arteries are involved in the anastomosis? (X2)
Anterior and posterior inter ventricular arteries
Circumflex and right coronary artery
The anastomoses connect branches from the right and left
Trye
Where does the circumflex travel?
Circumflex is from the left coronary artery
It bends around the back of the heart, in the coronary groove
What surface of the heart does the anastomoses occur?
Posterior surface of the heart
The great cardiac vein lies along which artery?
Left anterior descending/inter-ventricular artery
Left circumflex artery supplies
La
Lv
Left anterior descending artery supplies
RV
LV
Interventricular septum
Left marginal artery supplies?
Left ventricle
Right marginal artery supplies?
Right ventricle
Apex
The middle cardiac vein anastomoses with which vein?
Great cardiac vein
So great on the front
Middle on the back, but anastomoses on the front
The anastomoses between the great and the middle cardiac vein, occurs on the anterior or posterior surface?
(Knowing that the great vein is on the anterior surface)
Anterior surgace
The middle cardiac vein lies alongside which artery?
The post inter-ventricular artery
The small cardiac vein lies alongside which artery
Right marginal artery
Which artery does the coronary sinus lie alongside by?
Circumflex artery
The coronary sinus drains into the right atrium , true or false
True
The anterior cardiac veins drain into what
Directly into the right atrium
Very small anterior cardiac veins drain where?
Directly into the right strium
We know that the heart has intrinsic contraction via the purkinje cells in the SA and AV nodes. But is the extrinsic contraction as well?
Yah
the intrinsic conduction of the heart can be controlled by which nerves? (Generally speaking)
Extrinsic nerves
During a heart attack, why does pain radiate to the inner surface of the upper arm?
Because they share spinal nerves
Both the heart, visceral layer of the serous pericardium, and the inner surface of the upper arm share innervation from t1-4 sympathetic ganglia
Which nerve is carries pain, and innervates the fibrous pericardium and the parietal layer of the serous pericardium?
Phrenic nerve
What does the phrenic nerve innervate?
innervates the fibrous pericardium and the parietal layer of the serous pericardium
Which nerves are involved in changing heart rate?
Vagus
Cervical and upper thoracic sympathetic ganglia (T1-4)
Which nerve innervates the heart to decrease heart rate?
Vagus
If vagus is para, what’s Sympa for the heart
Sympathetic cardiac nerves
Cervical and upper thoracic (t1-4)
What do the sympathetic ganglia innervate in the heart anyways?
Heart muscle
Visceral layer of serous pericardium
What does the vagus innervate (heart)
Heart muscle
Visceral layer of serous pericardium
What does the phrenic nerve innervate?
Fibrous pericardium and parietal layer of serous pericardium
What does the sympathetic innervation of the heart actually do?
Increase heart rate
Increase force of contraction
What’s an enlarged heart called and most common reason for it?
Cardiomegaly
Cardiac failure
Dextrocardia?
Heart completely the wrong way around
What does the heart lie against posteriorly?
Oesophagus
What openings are in the right atrium? (3)
IVC
SVC
Coronary Sinus
How many auricles are in the heart?
2
Purpose of auricle
To increase capacity of atrium, and so also increase the volume of blood that it is able to contain
Basically a muscular pouch
Where is the right auricle in the right atrium?
Extending from the antero-medial portion of the chamber
The interior surface of the right atrium can be divided into two parts by a muscular ridge called
Crista terminalis
The fossa ovalis of the interatrial septum of the heart is a remnant of which embryonic structure?
Foramen ovale
What’s the foramen ovale
Of fetal heart
Allows right to left shunting of blood to bypass the lungs
It closes once the newborn talked its first breath
What is the solid muscular wall that separates left and right atria called?
The interatrial septum
What does the fossa ovalis look like?
A small oval shaped depression
Which is adult, foramen ovale or fossa ovalis?
Fossa ovalis
Foramen ovalis was in the fetal heart
False
Foramen ovale
Finish this… of adult heart we see the fossa
Ovalis
What’s patent Foramen ovale
An atrial septal defect, an abnormal opening in the interatrial septum, in the Foramen ovale
I’m saying Foramen ovale cuz it’s a baby issue, but yes, continues into adulthood of the fossa ovalis
What’s the right atrioventricular orifice
Where blood is pumped through, guarded by the tricuspid valve, (into the right ventricle)
What’s the left atrioventricular orifice guarded by
The mitral valve
Where does the left auricle extend from?
Superior aspect of the chamber, overlapping the root of the pulmonary trunk
Location of coronary sinus?
Between inferior vena cava orifice, and right atrioventricular orifice
Interior surface of the left atrium can be split into the inflow portion and the outflow portion. What is the embryo logical origin?
Inflow: derived from the pulmonary veins themselves
Outflow: derived from the embryonic atrium
Inflow portion of the left atrium includes the left auricle
False
Outflow includes the left auricle
What is the outflow portion of the left atrium lined by
Pectinate muscles
What’s the supraventricular crest (3)
A muscular ridge
Found in the right ventricle
Separates the inflow and outflow portion of the ventricle
The inflow part of the right ventricle is covered by a series of irregular muscular elevations- what are these called
trabecular carnae
What do the papillary muscles attach to?
Fibrous cords called the chordae tendinae
What do the chordae tendinae attach to
Tricuspid valve cusps
How is prolapse of the valve leaflets prevented during ventricular systole?
Papillary muscles pull on the chordae tendineae to prevent prolapse of the valve leaflets.
How is the outflow portion of the right ventricle visibly different to the rest of the right ventricle?
Smooth walls
No trabeculae carneae
Outflow portion of the right ventricle leads to what
Pulmonary artery
What is the outflow portion (corpus arteriousus) of the right ventricle derived from?
The embryonic bulbus cord is
The Interventricular septum separates the two ventricles, it’s made up of two parts, what are they?
Superior membranous part
Inferior muscular part
Interventricular septum has a membranous part, and an inferior muscular part.
(Separates ventricles)
Which part forms the majority of the septum? Which part is part of the fibrous skeleton of the heart?
Muscular part is the majority of the septum and is the same thickness as the left ventricular wall.
The membranous part = fibrous skeleton of the hearts
Inflow portion of the left ventricule is lined by what
Trabecular carnae
The outflow part of the left ventricle is known as what
The aortic vestibule
Outflow part of the left ventricle is known as the aortic vestibule. Is the derivative of what embryonic part
Bulbus cordis
What’s the crest in the right atrium called
Crista terminalis
How many papillary muscles in the right ventricle?
x3
Purpose of trabeculae carnae?
Probably to prevent suction
Where is the moderator band? (2)
It’s in the right ventricle
Stretches from the ventricular septum to the anterior wall
Purpose of the moderator band of the right ventricle
Holds anterior wall, keeps it from over expanding
Also has important conductive function, containing the right bundle branches
What does the moderator band conduct?
Impulses from the bundle of His to the right ventricular wall
4 things in the hearts conducting system?
Sinoatrial nose
Atrioventricular node
Bundle of His (atrioventricular bundle)
Purkinje fibres
Sequence of heart conduction??
Signal conduction created by SA node
Spreads across atria, causing them to contract
Reached AV node therefore DELAYS
Conducted down bundle of His in septum
Purkinje fibres and bundle of His spread the wave impulses along the ventricles, causing them to contract
Parasympathetic decreases during node of the SA node, and is the vagus nerve
Trueeee
Sympathetic nervous system increases firing rate if SA node, and is cervical and upper thoracic ganglia (T1-4)
Yes
Where is the AV node located
Near the opening of the coronary sinus
Where’s the coronary sinus located?
Right atrium
The AV node acts to delay the impulses by approximately how much
120ms
The bundle of his has three branches?
No, has two
Right bundle branch- conducts the impulse to the purkinje fibres of the right ventricle
Left bundle branch- conducts the impulse to the purkinje fibres of the left ventricle
What are the purkinje fibres architecturally?
A network of specialised cells, abundant with glycogen, and have extensive gap junctions
Where are the purkinje fibres located in the ventricular walls?
In the subendocardial surface, can transmit action potentials from bundle of His to the myocardium of the ventricles
How are pacemakers connected to the heart?
Wires, through the venous system
Most common indicator for a pacemaker?
Bradycardia
Once inserted, the pacemaker monitors the heart rate, and only fires of the rate becomes too slow
Papillary muscles, how many?
3 on the right side (tricuspid)
2 on the left side (mitral valve)
The left atrium has how many openings for veins?
4
L and r superior pulmonary veins
L and r inferior pulmonary veins
The left atrium lies wholly postero-superiorly against the what
Oesophagus
Which a or v forms the base of the heart
Left atrium forms the posterior surface of the hwaft
How does the wall of the left ventricle compare to the right ventricle wall?
Wall of left 3 times as thick as right ventricular wall
Which a or v forms the apex of the heart?
The left ventricle
How many valve cusps on the left ventricle?
2 (biscuspid)
Where is the trabecular carnae located?
Only the ventricles
Once signal through bundle of His, then impulses will go down p fibres, and then what layers?
Through myocardium, then to the epicardium
Aortic valve listen where?
Right 2nd intercostal space next to the sternum
Pulmonary valve listen where?
Left 2nd intercostal space next to the sternum
Tricuspid valve listen where?
Left 5th intercostal space next to the sternum
Mitral valve listen where?
Left 5th intercostal space and midclavicular line?
Apex bear palpated where?
5th left intercostal space , mid clavicular
Explain to me the branches of the superior vena cava?
Right: right brachiocephalic, off that is right internal and external jugular veins, becomes right subclavian
Left: left brachiocephalic, off that is left internal and external jugular vein, becomes left subclavian vein
Brachiocephalic > internal and external jugular > Brachiocephalic becomes right subclavian
Is this true for both left and right?
Yes
What branches of superior vena cava, and travels down inferiorly? (On the right)
Azygous vein
On both sides, the brachiocephalic becomes the subclavian after the two jugular branches. But BEFORE the jugular branches, there’s a branch off the superior vena cava, what are these two branches (travel inferiorly, lateral to the azygous)
The internal thoracic veins
What do the internal thoracic veins give off?
Anterior thoracic veins
What gives off the right posterior thoracic intercostal veins?
The RIGHT posterior thoracic intercostal veins are given off by azygous vein
What gives off the left thoracic intercostal veins? (2)
The accessory hemi-azygous vein and the azygous vein
These both come of the azygous
Which artery lies alongside the internal thoracic vein, (which ends up giving of anterior thoracic veins, whilst the azygous gives off the posterior thoracic veins)
The internal thoracic artery
What do the anterior intercostal veins anastomose with?
The posterior intercostal veins
Same with the arteries
The thoracic duct follows the course of what vein
Azygous vein
Subclavian artery arises from what?
Aortic arch
Subclavian artery becomes what
Axillary
When does subclavian artery become axillary?
Lateral border of 1st rib
Axillary artery becomes what artery in the upper arm?
Brachial
Brachial artery divides into what
Radial and ulnar in the cubical fossa
Radial and ulnar give off what arteries in the palm?
Digital arteries
The subclavian vein branches into what
Axillary (becomes basilic) and cephalic
Early on branch of the axillary vein?
Brachial vein
So the subclavian becomes the cephalic and the basilic. Which is lateral and which is medial.
The basilic (from axillary) is the medial
The cephalic is the lateral vein
Which vein connects the cephalic and basilic across the cubical fossa?
Medial cubical vein
Which vein from the upper limb do you take blood from?
The median cubital vein, which connects cephalic and basilic across the cubital fossa
Aorta leads to external iliac. In the anterior thigh, this becomes what
common femoral
What does the common femoral artery give off (2 branches)
Deep femoral and superficial femoral
What does the superficial femoral artery become
Popliteal
What does the popliteal artery (which came off the superficial femoral) become? (2)
Anterior and posterior tibial
Posterior tibial (from popliteal) artery gives off a branch, then continues medically down to plantar surface of the foot. What does it give off?
The fibular
(used to be known as the peroneal)
Anterior tibial (from the popliteal) continues down anteriorly to what, to become what
Dorsum of the foot, to become the dorsalis pedis
The anterior tibial continues to the dorsum of the foot, to become the dorsalis pedis between which toes?
1st and 2nd
Where do the superficial veins arise from?
Dorsal arch of the foot
Long/great saphenous vein travels up the limb medically to drain into what bigger vein
Femoral
Short/ small saphenous vein drains into what ‘larger’ vein
Popliteal
Basic structure of a blood vessel
Basic structure of blood vessels:
1) tunica intima
2) tunica media
3) tunica external
Endocardium is the same as the tunica intima
True
Endocardium and tunica intima is what structurally
Endothelium and basement membrane and connective tissue
Myocardium and tunica media are the same, what is it structurally
Muscle and elastic tissue
Epicardium is the same as
Tunica external (adventitia)
But the epicardium has epithelium as well as fibrous connective tissue, whereas the tunica externa/adventitia is just fibrous connective tissue
What’s the tunica media of a blood vessel made of
Muscle and elastic tissue
The endocardium is what type of cell
Simple squamous epithelium sitting on a basement membrane, and on connective tissues
The heart chambers are lined by what?
Endocardium
The valves are made of what
Endocardium
The epicardium is the inner layer of the heart wall
False outer,
Then it’s peri cavity, then parietal
Then fibrous pericardium
In which layer of the heart is main branches of coronary arteries located
Epicardium
Architecturally what’s the epicardium made of
Simple squamous epithelium and basement membrane and connective tissues
Artery vs vein had a thin vs thick adventitia
Artery = thin adventitia
Vein = thick adventitia
What are valves
To prevent back flow
Basically endothelial projections into lumen
What are the three types of arteries?
Elastic
Muscular
Arterioles
Three examples of elastic arteries
They’re large conducting arteries….
Aorta
Common carotid
Pulmonary
Radial, femoral, coronary arteries, are what type of arteries?
Muscular
“Pressure reservoir” describes which type of artery
Elastic arteries eg aorta
Recoil of elastic arteries is due to presence of what
Extensive amounts of elastic fibres in the tunica media
Elastic fibres in arteries are secreted by what
Smooth muscle cells
Layers of elastic fibres (eg in tunica media of elastic arteries) are called what
Laminae
Purpose of muscular arteries
Controls distribution of blood (vs elastic which is pressure reservoir)
Is there elastic laminae in tunica media of muscular arteries eg femoral?
No
Thick tunica media of muscular arteries has what cells
Smooth muscle cells
Elastic fibres in muscular arteries are concentrated in what sheets
(Epithelium)
Internal elastic lamina
(Then tunica media)
External elastic lamina
(Then tunica adventitia)
Are there elevator fibre sheets in arterioles? Like there are in muscular arteries? (Internal and external elastic lamina)
No
Is there tunica Adventitia in arterioles?
No
There is rich sympathetic nerve innervation in arterioles
True
Arterioles control blood pressure
True
Arterioles control blood flow to capillary beds
True
Why is there no tunica media, or tunica Adventitia, and only very thin tunica intima in capillaries?
Because main exchange site for nutrients
When is the tunica adventitia lost?
In arterioles
What are pericytes?
Incomplete layers of cells surrounding the capillary, have contractile properties which control blood flow
Blood pressure in capillaries is high
No los
Three types of capillaries?
Continuous
Fenestrated
Discontinuous
How does material pass through a continuous capillary? (Eg they’re in muscle)
Must pass through the cell, or between cell (junctions control)
Continuous capillary and control?
They can control what is exchanged
Why called Fenestrated capillary, and where?
They have Fenestrations (or pores)
Eg endocrine glands
Discontinuous capillaries called why
Gaps between endothelial cells (and BM)
Therefore allow free passage of fluid and cells
Discontinuous capillaries where example? (3)
Liver, spleen, bone marrow
Where are sinusoids found
Where large amount of exchange takes place eg liver
What are sinusoids
Large diameter type of discontinuous capillaries
The t. Intima of sinusoids contain what
Phagocytic cells
Purpose of arteriovenous (AV) shunts
To bypass capillary beds eg in skin for thermoregulation
Lumen of veins and Venules is smaller than arteries
False
Larger
Histologically, veins and venues have thin tunica intima, media, and adventitia
Yea
Superficial veins have surrounding support, but deep veins don’t
False
Deep veins have surrounding support, superficial veins dont
Surrounding support for deep veins, is in the form of what
Deep fascia and muscles
Which has thick walls, which has thin, superficial or deep veins?
Deep = thin walled
Superficial = thick walled
Where does the lymphatic system drain into?
The systemic venous system
Lymphatic system drains tissue fluid lost from where
Capilaries
Flow in lymphatics are directed by pressure differences
No
VALVES
What are lymph capillaries
Blind ended capillaries, lined by very thin endothelium
Are there red blood cells in the lumen of lymph capillaries
No
Purpose of anchoring filaments in lymph capillaries
Anchoring filaments- fine collagenous filaments, link endothelial cell to surrounding tissue, keeping lumen open.
Nerve supply of blood vessels?
Sympathetic and para
Blood supply to blood vessels is in the form of what?
Vasa vasorum
Lymphatics of blood vessels is in what layer?
Tunica adventitia
