Anatomy- unit 1
Terms
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copy deck
- Ovaries
- attached to post wall of broad ligament, intraperitoneal organ.
- Broad ligament
- double layer of peritoneum, attaches the uterus to lateral wall and floor of the pelvis
- Round ligament
- connects uterus to labia major. The round ligament develops from the gubernaculum which attaches the gonad to the labioscrotal swellings in the embryo.
- Uterine tubes
- has laterally from uterus from the free margin of the broad ligamemnt. has ampulla(place of fertilization), isthmus,infundibulum, fimbrae
- Cervix
- part of uterus tht enters the vagina, is nipple shaped
- Inguinal canal
- The inguinal canal is a passage in the anterior abdominal wall which in men conveys the spermatic cord and in woman the round ligament. The inguinal canal is larger and more prominent in men
- Vasculation of uterus and ovaries
- uterine arteries and ovarian arteris .. from internal iliac artery
- Fornix
- the space tht surrounds the cervix in the vagina.
- Hemmorroids
- common prob for pregnant women, the uterus is puahing against the rectum and not allowing blood back its usual way(blocking venous return)
- Scrotum
- outside sac tht houses testes, made up of: skin, dartos fascia, dartos muscle. purpose seems to be to keep the testicles at a lower temp tht body temp
- Epididymis
- testicular structure posterior aspect of testes, which receives sperm from testes and houses them until maturity
- Ductus (vas) deferens
- receive sperm from epididymis, large duct tht goes to the prostrate
- lateral umbilical fold
- important landmark for male rep system..passage of tubes and vessels
- Seminal vesicles
- retropeneal, glandular tissue that are inferior and posterior to the bladder
- Spermatic cord
- contains:vas deferens, testicular artery, pampinoform venus plexus,
- Pampinoform Venus plexus
- a plexus of veins that comes begins in the testis and comes together to form the testicular vein
- Deep inguinal ring
- made from the outpouching of the transvelis fascia,Lies at the midpoint of the inguinal canal, lateral to the umbilical folds
- Tunica vaginalis
- a pouch of serous membrane, derived from the saccus vaginalis (processus vaginalis) of the peritoneum, which in the fetus preceded the descent of the testis from the abdomen into the scrotum.
- Serous membrane
- serous membrane is composed of a secretory epithelial layer and a connective tissue layer underneath. The epithelial layer, known as mesothelium, consists of a single layer of avascular flat nucleated cells (simple squamous epithelium) which produce the lubricating serous fluid. This fluid has a consistency similar to thin mucous. These cells are bound tightly to the underlying connective tissue. Peritoneum, Pleura, Pericardium
- Gubernaculum
-
The gubernaculum connective tissue that connects to the developing testes to the area that is going to be the scrotum (this process also occurs in the ovaries).
Gubernaculum governs the descent of the testes - Spermatic cord covering
-
external spermatic fascia – external abdominal oblique aponeurosis
(2)cremaster muscle and fascia – internal abdominal oblique muscle and aponeurosis
(3)internal spermatic fascia – transversalis fascia - indirect inguinal hernia
-
lateral to lateral umbilical fold – passes through deep inguinal ring
protrudes through the inguinal ring and is ultimately the result of the failure of embryonic closure of the internal inguinal ring after the testicle passes through it. It is congenital - Direct inguinal hernia
-
medial to inferior epigastric artery (lateral umbilical fold) –inguinal triangle
Not covered by the internal spermatic fascia. - Penis
-
contains the following: a.prostatic urethra
b.membranous urethra
c.spongy urethra
d.urethral orifice - glans penis
e.corpora cavernosa
f.corpus spongiosum - Ectoppic pregnancy
- one in which the fertilized ovum is implanted in any tissue other than the uterine wall. Most ectopic pregnancies occur in the Fallopian tube (so-called tubal pregnancies), but implantation can also occur in the cervix, ovaries, and abdomen.
- Thorax
- area between neck and abdomen, it houses heart, neck, strcutures tht vascularize the head,neck and upper extremities. the diaphragm separeates the thorax and abdominal region
- Rib cage
-
-12 thoracic vertebrae
-ribs 1-7: called "true ribs"
ribs 8-10 "false ribs"
ribs 11-12 "floating ribs" - True ribs
- ribs attached to the sternum via costal cartilage
- False ribs
- indirect connection with sternum
- Floating ribs
- no connection to sternum
- Vertebral column
-
o Posterior aspect of the abdominal wall
o12 Thoracic vertebrae
o12 pairs of ribs that articulate with the 12 thoracic vertebrae
oAnteriorly, the ribs are attached to sternum - Sternum
- 3 parts: anubrium, body and xyphoid process
- Manubrium
- Inf to jugular notch,A triangularly (shield) shaped bone, which lies at the level of T3 and T4 vertebrae (clavicle and 1st 2 pairs of ribs)
- Body of sternum
- longest piece, costal cartilage articulates with it.
- xyphoid process
- lowest part of the sternum
- infrasternal angle
- angle below sternum, cartilages of ribs 7-10 ascend and join to make infrasternal angle and costal margin
- Contents of the thoracic cage
- provides protection to viscera in which it sits in, cartilaginous disks or intervertebral disks, between each vertebrae, which serve as a cushioning and protection for the vertebra. Pectoralis major and pectoralis minor sit on top of t.cage, on the anterior side.
- Intercostal space
- filled by 3 layers of muscles (intercostal muscles) and connective muscle. Internally lined by serous membrane.
- Exterior Intercostal muscle
- origin is the inferior margin of the above rib. It extends Medially and Inferiorly. It inserts into the superior border of the rib below. Anteriorly, muscles are replaced by exterior intercost memebrane(thin, translucent membrane that attaches muscle to the sternum)
- Costachondral junction
- junction of cartilage and bone
- Interior Intercostal muscle
- origin is theinferior margin of the above rib, it extends LATERALLY and INFERIORLY. It inserts superior border of the rib below. At costal angle- replaced by membrane
- VANS (Veins, Arteries, Nerves)
- deep to the interior intercostal muscles, you from sup to inferior veins,arteries n veins
- Inner complex Muscles
- transversus thoracis, innermost intercostal, subcostal
- Transversus thoracic
- most anterior muscle, origin is the inf aspect of the sternum. Insertion: internal surfaces of 2nd-6th costal cartilages
- Innermost intercostal
-
-Origin: inferior border of the rib above
-Insertion: superior border of the rib below
-Their orientation is the same as the internal intercostals muscles (inferiorly and laterally)
-Veins, arteries, and nerves lies between innermost and internal intercostals muscles
-No membrane - Subcostal
-
-Located towards the back part of the rib, furthest from the sternum
-Origin: inferior margin of the rib above
-Insertion: jumps 1-2 ribs
-Muscles are directed towards the angle of the rib (they have an oblique angle) - Pleura
- serous membrane consists of mesothelial cells and connective tissue, secretes fluid for lubrication.
-
BV To intercostal space:
Subclavian artery -
-branch of the aorta on the left side of the body
-It’s from the brachiocephalic trunk on the right side of the body.
-It branches to give off internal thoracic artery -
Int.costal vascul. :
Internal thoracic artery -
o Travels on the inner aspect of the thorax, lateral to the sternum
o Along the way down the sternum it gives off branches called anterior intercostals arteries which supply blood to the intercostals spaces 1-6
o It goes to the 6th intercostals and divides into 2 terminal branches:
 Musculophrenic  supplies the diaphragm and intercostal spaces 7-9 via anterior intercostals arteries
 Superior Epigastric  supplies anterior abdominal wall (anestomoses with inferior (from iliac) epigastric) - Superior intercostal artery
-
-From 3rd all the way down to the 11th intercostals space are branches from the thoracic aorta
-The posterior intercostals arteries in the first 2 intercostal spaces come from superior intercostals or highest intercostals artery. - Veins (intercostal ribs)
-
-Anterior intercostal veins from the 7th, 8th, 9th intercostal spaces drain into the musculophrenic vein
-Musculophrenic vein unites with superior epigastric vein to for the internal thoracic vein.
-The internal thoracic vein picks up anterior intercostal veins from the 1st through 6th intercostals spaces
-The internal thoracic vein then drains into the right and left brachiocephalic veins which goes toward the heart.
-Posterior intercostal veins drain into the azygous venous system - Internal thoracic vein
- Musclopherenic and superior epigastric veins join to form internal thoracic vein
- Azygous venous systtem
-
The azygos system of veins is considered to be the azygos vein, along with its left-sided counterparts, the hemiazygos vein and the accessory hemiazygos vein. Together, they form an anastomosis between the superior vena cava to the inferior vena cava.
It can be noted that the azygos system of veins exists because the superior vena cava and the inferior vena cava are not continuous - Parietal pleura
- pleura that lines the cavities, costal pleura-> lines gainst rib cage, diaphragmic pleura lines against diaphragm. Cervical pleura lines against the neck.
- Mediastinum
-
-Space that exits in the midline from the diaphragm to the superior thoracic aperture in the thorax.
-This is the space where heart and great vessels are situated - Superior mediastinum
-
space above the sternal angle and T4-T5
-It contains the great vessels - Inferior mediastinum
-
space which includes the rest of the mediastinum which is divided into:
-Middle Mediastinum : contains the heart and its pericardium
- Anterior mediastinum: space between the sternum and the pericardium of the heart
-Posterior Mediastinum: spaces between the pericardium of the heart and the vertebrae.
-The esophagus runs from the superior mediastinum into the posterior mediastinum - Costodiaphragmic recess
- area in pleural cavity that does not contain lungs. It is located between the diaphragm and the rib cage, below the 8th rib.
- Lungs
-
Right: Has three lobes: posterior, middle, and inferior
Has an Oblique fissure: separates the middle and inferior lobe
And a Horizontal Fissure:separates the superior lobe from the middle - Trachea
- continues with the larynx,main air passage way, divides at sternum angle into prim bronchi (considered to be the dividing line btwn inf and sup medistinum)
- Primary bronchi
- form the root of the lungs and divide into secondary bronchi. Left prim is more oblique, smaller (in diameter) and longer. Right prim oblique is vertical, shorter and largerin diameter.
- Secondary Bronchi (lombar)
-
brings air into the lungs,
-Right lung has 3 lobes : 3 secondary bronchi
-Left lung has 2 lobes : 2 secondary bronchi
-secondary Bronchi dived into tertiary bronchi (also called segmental bronchi) - Tertiary bronchi
-
brings air into one section of the lung
-Each segment is a bronchopulmonary segment - Hilum of lungs
- where the structures of the root of lungs enter the lungs.
- Nerves of thoracic wall
-
T1-T11: intercostal nerves,, T7-T11-> Thorocoabdominal nerves
T12- Subcostal nerve - Superior vena cava
- formed by the union of the left and right brachiocephalic veins
- Thoracic ducts
- it is the largest lymphatic vessel in the body. It collects most of the lymph in the body (except that from the right arm and the right side of the chest, neck and head, which is collected by the right lymphatic duct) and drains into the systemic (blood) circulation at the left subclavian vein.
- Branches of Thoracic aorta
- R and L coronary, brachiocephalic, L common carotoid, L subclavian, post intercostal arteries, bronchial arteries, esophageal arteries.
- Pulmonary trunk
- comes from the right ventricle, dives into L and R pulmonary arteries, takes blodd away from the heart and into Ln R lungs.
- Coronary arteries
- supplies blood to the heart, arises form ascending aorta.
- Right coronary
-
o Right coronary artery comes off of the right coronary sinus which is inside the aorta. It then travels to the inferior margin of the heart in the sulcus and gives off branches as it goes along.
-In the margin it gives off the marginal artery
-In the posterior potion on the interventricular groove it gives off the posterior interventricular artery
-Right coronary artery vascularizes the right atrium and ventricle as well as the SA and AV nodes - Left Coronary
-
-On the anterior surface, the left coronary artery comes out of left coronary sinus in the ascending aorta and divides into 2 branches:
-Circumflex artery : anastamoses with the right coronary artery. It vascularizes the left atria and left ventricle
-Anterior Interventricular artery :anastomoses with the posterior interventricular artery and vascularizes the right and left artery. - Coronary sinus
-
It is a vein that collects blood from the myocardium of the heartIt is located between the left atrium and ventricle on the posterior surface of the heart.
It runs transversely in the groove between the left atrium and ventricle on the posterior surface of the heart.
The coronary sinus orifice (opening) is just superior to the septal leaflet of the tricuspid valve. -
Great Cardiac Vein
Middle Cardic Vein -
⬢Great Cardiac Vein: in anterior interventricular groove, lies with the anterior interventricular artery and drains into the coronary sinus
⬢Middle Cardiac Vein: in posterior interventricular groove, lies with the posterior interventricular artery, and drains into the coronary sinus - Ligamentum arteriosum
- connects left pulmonary artery to aortic arch
- Aortic Arch
- has 3 branches (R to L): Brachiocephalic branch (goes superior to the neck and splits into right carotoid, righth subclavian), Left common carotid(head and neck), left subclavian(neck and upper extremities).
- Brachiocephalic vein
-
superficial but deep to thymus. L and R--> SVC
Each brachiocephalic vein is formed by the union of subclavian vein and jugular vein. - Hemiazygous vein
-
a vein running superiorly in the lower thoracic region, just to the left side of the vertebral column.
-Receives blood from the posterior intercostals veins found in the 9th-11th intercostal spaces plus the left subcostal vein
-Runs toward the right passing under the aorta and esophagus and drains into the azygous - Accessory hemiazygous vein
-
in combination with the hemiazygous vein, they form the left side equivalence of the azygous vein. They drain most of the posterior intercostal veins.
-The posterior intercostals veins of the 4th-8th left posterior intercostals spaces drain into the accessory hemiazygous
-It also drains into the azygous and travels under the aorta and esophagus - Vagus (X) cranial nerve
-
⬢ Comes from the medulla in the brain, through the neck, through the superior thoracic aperture, crosses the superficial aspect of the aortic arch (between the left subclavian and left common carotid). The vagus nerve supplies motor parasympathetic fibers to all the organs except the suprarenal glands, from the neck down to the second segment of the transverse colon. The vagus also controls a few skeletal muscles, namely:
Levator veli palatini muscle
Salpingopharyngeus muscle
Palatoglossus muscle
Palatopharyngeus muscle
Superior, middle and inferior pharyngeal constrictors
Muscles of the larynx (speech). - Left recurrent laryngeal nerve
-
Comes off the left vagus just to the left of the ligamentum arteriosum.
The left recurrent laryngeal nerve is a mixed sensory and motor nerve that goes next to the ligamentum arteriosum, behind the aorta, travels in a groove in between the trachea and esophagus and goes all the way up to the larynx. - Esophageal plexus
- The esophageal plexus is formed by fibers from two sources: 1.branches of the vagus nerve 2.visceral branches of the sympathetic trunk. The esophageal plexus and the cardiac plexus contain the same types of fibers and are both considered thoracic autonomic plexus(es).
- Phrenic nerve
-
⬢Is a sensory nerve to the pericardium
⬢It is a mixed nerve (sensory and motor) to the diaphragm
⬢It is anterior to the root of the lung
The right phrenic nerve passes over the right brachiocephalic artery, the subclavian vein, and the superior vena cava and then crosses the root of the right lung and then leaves the thorax by passing through the vena cava hiatus opening in the diaphragm at the level of T8. The right phrenic nerve passes over the right atrium.
The left phrenic nerve passes over the left ventricle and pierces the diaphragm separately.
Both these nerves supply motor fibres to the diaphragm and sensory fibres to the fibrous pericardium, mediastinal pleura and diaphragmatic peritoneum. - Greater Splanchnic
- arises from the fifth through ninth thoracic ganglia (T5-T9) of the sympathetic trunk. The nerve travels through the diaphragm and enters the abdominal cavity, where its fibers synapse at the celiac ganglia. The nerve contributes to the celiac plexus, a network of nerves located in the vicinity of where the celiac trunk branches from the abdominal aorta. The fibers in this nerve modulate the activity of the enteric nervous system of the foregut. They also provide the sympathetic innervation to the adrenal medulla, stimulating catecholamine release.
- Lesser Splanchnic
-
T10-T12
arises from the tenth through twelth thoracic ganglia of the sympathetic trunk. The nerve travels inferiorly, lateral to the greater splanchnic nerve. Its fibers synapse with their postganglionic counterparts in the celiac ganglia, or in the aorticorenal ganglion. The nerve modulates the activity of the enteric nervous system of the midgut. - Least Splanchnic
-
T12-l2
arises from the twelfth thoracic to second lumbar ganglia of the sympathetic trunk. The nerve travels into the abdomen, where its fibers synapse in the renal ganglia. - Right superior intercostal veins
-
-Receives blood from the posterior intercostals arteries that are found in the 1st and 2nd intercostals spaces
-Drains into the azygous - Left superior intercostal veins
-
-1st to 3rd intercostals veins drain into the left superior intercostals vein
-The left superior intercostal vein drains into the left brachiocephalic vein which drain into the superior vena cava. - Pericardium
- double-walled sac that contains the heart and the roots of the great vessels.There are two layers to this sac: the fibrous pericardium and the serous pericardium. The serous pericardium, in turn, is divided into two layers; in between these two layers there is a potential space called the pericardial cavity.
- Fibrous pericadium
- is the most superficial layer. It is a dense connective tissue, protecting the heart, anchoring it to the surrounding walls, and preventing it from overfilling with blood. It is continuous with the outer adventitial layer of the neighboring great blood vessels.
- Serous pericardium
-
is deep to the fibrous pericardium. It contains two layers, both of which function in lubricating the heart to prevent friction from occurring during heart activity.
The layer next to the fibrous pericardium is the parietal layer.
The layer next to the heart is the visceral layer, also known as the epicardium.
Together these two layers form a continuous uninterrupted membrane. Between these two layers exists a small cavity called the pericardial cavity, which contains a supply of serous fluid.The serous fluid that is found in this space is known as the pericardial fluid. - Right atrium
-
contents:
pectinate muscles
superior and inferior vena cavae
coronary sinus
Interatrial septum – fossa ovalis - Left atrium (and autricle
-
pulmonary veinsAtrioventricular orifices and valves
a.tricuspid – right atrioventricular valve
b.mitral (bicuspid) – left atrioventricular valve - Trabeculae carnae
-
rounded or irregular muscular columns which project from the whole of the inner surface of the ventricle, with the exception of the conus arteriosus.
They are of three kinds:
some are attached along their entire length on one side and merely form prominent ridges,
others are fixed at their extremities but free in the middle,
while a third set (musculi papillares) are continuous by their bases with the wall of the ventricle, while their apices give origin to the chordæ tendineæ which pass to be attached to the segments of the tricuspid valve. - Papillary muscles
- serve to limit the movements of the mitral and tricuspid valves and prevent them from being inverted. They do not close or open the valves, which close passively in response to pressure gradients. Instead they brace the valves against the high pressure.
- Chordae tendineae
- are cord-like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve in the heart.
- SA Node
- the impulse generating (pacemaker) tissue located in the right atrium of the heart. It is a group of cells positioned on the wall of the right atrium, near the entrance of the superior vena cava. These cells are modified cardiac myocytes. They possess some contractile filaments, though they do not contract.
- AV node
-
is the tissue between the atria and the ventricles of the heart, which conducts the normal electrical impulse from the atria to the ventricles.
The AV node receives two inputs from the atria: posteriorly via the crista terminalis, and anteriorly via the interatrial septum.[1]
An important property that is unique to the AV node is decremental conduction. This is the property of the AV node that prevents rapid conduction to the ventricle in cases of rapid atrial rhythms, such as atrial fibrillation or atrial flutter. - AV bundle of (His)
- collection of heart muscle cells specialized for electrical conduction that transmits the electrical impulses from the AV node (located between the atria and the ventricles) to the point of the apex of the fascicular branches. The fascicular branches then lead to the Purkinje fibers which innervate the ventricles, causing the cardiac muscle of the ventricles to contract at a paced interval.
- Umbilical vein
-
⬢ One umbilical vein carries blood from the placenta to the fetus via the umbilical cord
⬢ The blood is about 80% saturated with oxygen (highest % found in fetal blood)
⬢Blood from the umbilical vein travels toward the liver but the majority bypasses the liver by passing through the ductus venosus which leads to the inferior vena cava
⬢A small amount of blood passes through the liver and mixes with blood from the portal venous system entering the liver from the fetal gut
⬢This mixed blood then exists the liver via the hepatic veins to enter the inferior vena cava, mixing with the blood from the ductus venosus
⬢The umbilical vein becomes the ligamentum Teres in adults - Right atrium of fetus
- ⬢ Most of the blood entering the right atrium from the inferior vena cava passes directly through the atrium towards the foramen ovale in the interatrial septum. It then passes through the foramen ovale into the left atrium.⬢ The blood in the right atrium that does not pass through the foramen ovale mixes with the blood entering the right atrium from the superior vena cava (blood from the fetal head and upper extremities) and coronary sinus. This combined blood enters the right ventricle
- foramen ovale
- passageway that allows blood to pass from right atrium to left atruim.
- ductus arteriotus
-
The ductus arteriosus brings blood into the aortic arch, thus allowing blood to bypass the lungs
⬢ The blood coming from the left pulmonary artery via the ductus arteriosus joins the blood in the aortic arch that comes from the left ventricle - Umbilical arteries
- branches off internal iliac arteries. ⬢ The right and left umbilical arteries (about 58% saturated with oxygen) carry this large quantity of blood to the placenta via the umbilical cord
- septum primum
- to initiate partritining of the atria, structure called septum primum grows from atrium wall.
- Foramen (ostium) primum
- As the septum primum begins to partition the atrium, an open space at the free border of the growing septum primum called the foramen primum is observed.It is obliterated once the septum reaches the endocardial cushion.
- Foramen(ostium) secundum
- Before the septum reaches the endocardial cushion perforations appear in the dorsal part of the septum primum which will soon form another opening called the foramen secundum. The septum primum eventually reaches the endocardial cushion obliterating the foramen primum. At this point the only foramen in the septum primum is the foramen secundum
- Septum secundum
- At about the same time the foramen primum is being obliterated, another membrane called the septum secundum begins to develop on the right side of the septum primum. The septum secundum gradually covers the foramen secundum. The oval shaped opening in the septum secundum is called the foramen ovale.
- Changes at birth
-
-The newborn begins to breathe (respiration starts)
-The ductus arteriosus constricts due to muscle contraction and closes
-The amount of blood flowing to lung increases
-The intraatrial pressure in the left atrium increases due to increase of blood returning from the lungs
-Blood flow decreases into the right atrium due to stoppage of flow from the placenta. Thus decreases the intraatrial pressure on the right atrium. - After birth effects on cardiovasc. system
-
⬢Umbilical arteries contract and close
⬢Umbilical vein and ductus venosus close and obliterate
⬢Ductus arteriosus collapses and closes
⬢The foramen ovale closes due to the increased pressure in the left atrium pushing the septum primum against the foramen ovale blocking its opening. - Primitive heart
-
fusion of the 2 endocardial tubes, forming one tube containing:
1.truncus arteriosus
2.bulbus cordis
3.ventricle
4.atrium
5.sinus venosus - Truncus arteriosus and bulbus cordis
-
When the heart assumes its S-shaped form the bulbus cordis lies ventral to and in front of the primitive ventricle.
The adjacent walls of the bulbus cordis and ventricle approximate, fuse, and finally disappear, and the bulbus cordis now communicates freely with the right ventricle, while the junction of the bulbus with the truncus arteriosus is brought directly ventral to and applied to the atrial canal. - Course of preganglionic sympathetic
-
ventral root white ramus communicantes - sym¬pathetic chain where they can do the following:
a. synapse in chain ganglion with postganglionic sympathetic neurons
b. pass through as splanchnic nerve to synapse in preaortic ganglia with postganglionic sympathetic neurons
c. The synapse between pre & postganglionic neurons is cholinergic - Postganglionic sympathetic
-
reach the target viscera (smooth or cardiac muscle or glands) via:
a.periarterial plexuses
b.direct sympathetic branches (i.e. cardiac sympathetic nerves)
c.gray rami communicantes to reach & distribute with spinal nerves
d.The synapse with the viscera is noradrenergic - preganglionic parasympath
-
They are cranioscaral, brainstem S2-S4. The preganglionic neuron cell bodies are found in nuclei in brainstem and in spinal cord. Their target is postganglionic neurons in parasympathetic ganglia.
2.Course of preganglionic fibers
a.cranial nerves III, VII, IX, and X to parasympathetic ganglia
b.pelvic splanchnic nerves to postganglionic parasympathetic neurons invisceral plexuses
c.synapse in enteric ganglia with postganglionic neurons cholinergic - postganglionic parasympaythetic
- Postganglionic fiber - usually short as enteric ganglia are located in or on viscera they innervate – The synapse with target viscera is cholinergic.
- Sympathetic innervation of thorax
-
preganglionic sympathetic neurons in lateral horn of thoracic spinal cord
2. exit via ventral root white rami communicantes sympathetic chain synapse with postganglionic neurons in sympathetic ganglia.
3. Postganglionic neurons distribute via:
a.periarterial plexuses
b.direct sympathetic branches (i.e. cardiac sympathetic nerves)
c.connect via gray rami communicantes to distribute with spinal nerves target visceral tissues. - Parasympathetic innerv of thorax
-
Preganglionic parasympathetic neurons cell bodies in dorsal motor nucleus of vagus (X) nerve. Axons distribute with that nerve to neck, thorax & abdomen.
a. cardiac parasympathetic nerves to cardiac & pulmonary plexuses (cholinergic synapses)
b. anterior & posterior esophageal plexuses & vagal trunks (cholinergic synapses)
2. Postganglionic parasympathetic neurons cell bodies found in cardiac & pulmonary plexuses and in esophageal wall. Postganglionic sympathetic neurons synapse with the target viscera (cholinergic synapses).
C. Cardiac and pulmonary plexuses are in vicinity of organs and also contain - Collateral ganglia
-
are sympathetic ganglia which lie between the sympathetic chain and the organ of supply. They are the site of relay of the preganglionic sympathetic fibres that supply abdominal and pelvic viscera.
These include the celiac ganglia, aorticorenal ganglion, superior mesenteric ganglia, and inferior mesenteric ganglia. - Pulpal morphology
- pulp cavity is divided into 2 areas: pulp chamber(coronal) and the root canal(radicular). It has 4 distinct layers: odontoblast, cell free zone, cell rich zone, core.
- Apical foramen
- hole at the tip of the root where blood vessels and nerves enter
- Rashclow's fibers
- myelinated nerves in the cell rich zone
- Odontoblastic cell body theory
-
theory of sensation tht says
⬢The process is stimulated->signals are propagated down to the soma ->nerve fiber is stimulated - Odontoblast process theory
-
⬢Process is stimulated -> nerve fiber is stimulated
No intermediate through the cell body - Nerve fiber theory
- Fiber is directly stimulated in the tubule.
- Dentin sensitivity
- Dentin is most sensitive at the DEJ/DCJ and DPJ, least sensitive in the areas between them. But process/fiber extends only 1mm into the tubule
- Hydrodynamic theory
- Extracellular fluid fills the tubules to transmit sensation
- Fibroblast in pulp
- when odontoblasts die, fibroblasts from cell rich zone migrate into the area of lesion and make reprative dentin.
- Reperative dentin
-
there are 2 types:
irregular reprative dentin- accute lesions.
regular reprative dentin-chronic slow moving lesions. - Layers of enamel organ (bell stage)
-
4 cell layers exist within the enamel organ:
-Outer enamel epithelium (OEE)
-Inner enamel epithelium (IEE)
-Stratum intermedia (overlying the IEE) (SI)
-Stellate reticulum (in between the SI and OEE) (SR) - Epithelial mesenchymal interaction
-
decides the fate of the early tooth.
Pre Bell: The mesenchyme (specialized surrounding connective tissue) determines the fate of the enamel organ (epithelial).
Post Bell: enamel organ determines the fate of the tooth - Histodifferentiation
-
-Cells of the IEE begin to change shape from squamous to columnar
-This process begins at a point furthest from the cervical loop of the enamel organ
-Then differentiation occurs from this point, out towards the loops
-For posterior teeth, this differentiation begins at the cusp forming regions (where the enamel knots are located) - von Korf's fibers
- collagen arranged in a fan shaped (preodontoblast)
- Mantle dentin Matrix
- secreted dentin from the preodontoblast
- Aprismatic enamel matrix
- secreted by the preameloblast along basement membrane.
- Enamel (initial)
- Enamelin, tuftlein, amelogen.
- Dentin tubule
- odontoblast process detach, the void created is called dentin tubule.
- Reduced Enamel epithelium
- primary enamel cuticle, OEE, SR, SI and post-ameloblasts.
- Hertwig’s Epithelial Root Sheath (HERS)
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-The cervical loop region begins to elongate apically
-Basement membrane continues to surround this growing region of OEE and IEE
-The structure becomes known as HERS. - coronary circulation
- Left ventricle -> ascending aorta –> coronary artery –> branching arteries –> branching veins –> coronary sinus –> right atrium
- morula
- collection of cells after cleavage (ball of cells)
- blastocyst
- embryonic stage after morula, it is a hollow ball of cells.
- Trophoblast
- embryonic portion of the placenta
- Epiblast
- layer of emnryoblast, will give rise to amnionblast cells
- Prochordal plate
- desmosomes plates between epiblast and hypoblast.
- primitive groove
- The depression that forms in the midline of the bilaminar germ disc
- primitive streak
- The edges of the depression in the bilaminar disk
- primitive node(aka Henson's node)
- fusion of the two primitive streaks occurs superiorly
- primitive pit
- where the deepest portion of the primitive groove occurs
- notochord process
- group of cells that will migrate into the primitive groove and divide anteriorly between the ectoderm and the endoderm will form notochord process. it has inductive properties.
- Neural plate
- flat layer of cells from overlying ectoderm tht is induced by notochord to become future nervous system.
- Buccopharyngeal plate
- use to be the prochordal plate, it seperates oral cavity and pharynx.
- Neurolation
- The phase in which the neural plate forms the neural tube in order to be submerged within the body is called neuralation
- Stromadeum
- primitive mouth
- Ectomesenchymal cells
- derived from neural crest, specialized CT of the head and ant portions of the neck.
- the formation of vertebrae, muscle mass and dermis of the skin
- mesoderm, somites
- Pharyngeal arches
- develop during the fourth and fifth week in utero as a series of mesodermal outpouchings on the left and right sides of the developing pharynx.
- 1st pharyngeal arch
- aka Mandible arch , gives rise to the Mandible and masticatory muscles, has cartilage called meckel’s, Cranial nerve V (trigeminal) is its associated nerve.
- 2nd pharyngeal arch
- also called Hyoid arch , gives rise to copula of tongue, styloid process and muscles of facial expression, cartilage : Reichert’s, cranial nerve: VII - facial
- 3rd pharyngeal arch
- stylopharygeal muscle, cranial nerve IX (glassopharyngeal nerve)
- 1st groove
- external ear, tympanic membrane
- 2nd groove
- hyoid arch covers 2nd - 6th groove..
- 1st pouch
- Eustachian tube, middle ear cavity, tympanic membrane
- 2nd pouch
- palatine tonsils
- 3rd pouch
- Thymus, inferior parathyroid
- 4th pouch
- superior parthyroid, thymus
- 5th pouch
- parfollicular cells of thyroid
- Intermaxillary segment
- formed from the fusion of the mesial nasel process. Intermaxillary process gives rise to the philtrum, tubercle, superior labial frenum, maxillary incisors, primary palate, and nasal septum
- Lateral Palatine shelves
-
from maxiallary processes, when the shelves fuse, they separate the nasal and oral cavities
-To fully seal off the region, they must also fuse with the primary palate
-incorrect fusion of this structure results in cleft lips/palates - Tongue formation
-
from 3 structures:
tuberculum impar, lateral lingual swellings (form ant 2/3 of tongue), post 1/3: is developed from the copula and epiglottal swelling - Hypobranchial emminence
- collectively copula and epiglottal swelling
- tongue innervation
- cranial V,VII,IX,X,XII(hypoglossal)
- Age of tooth development (fetus)
- about 6-8 weeks
- Cervical loop
- where IEE and the OEE meet
- Hepatic portal vein
- formed by the union of the splenic and the superior mesenteric veins. It drains into the liver (nutrient rich blood). Left and right gastric vein also drain into the liver.
- Greater Omentum
- is a large fold of peritoneum that hangs down from the stomach, and extends from the stomach to the transverse colon.
- Lesser omentum
- is a double layer of peritoneum which extends from the stomach and first part of duodenum to the liver.
- dorsal motor nucleus of the vagus nerve (CN X)
-
is made up of preganglionic parasympathetic neurons whose axons distribute with the vagus nerve to the body.
-It passes thru the neck ï‚® thorax (where it gives off branches to heart and lungs) ï‚® over esophagus ï‚® through diaphragm ï‚® abdomen ï‚® passes over stomach and small bowel ï‚® distributes all over the viscera to the transverse colon - lumbar cistern
- an enlarged subarachnoid space
- cauda equina
- (at end of cistern ) dorsal and ventral roots of spinal nerves
- Dorsal horn
- The dorsal horn is associated with processing sensory (afferent) input and is connected with the dorsal root of the spinal nerves
- ventral horn and lateral horn
-
⬢ The ventral and lateral horns are associated with motor (efferent) neurons
-The axons of these neurons form the ventral root of spinal nerves
-In the ventral horn, motor neurons to proximal muscles (trunk) are located medially and those for distal muscles are located laterally - primary afferent neurons
- sensory neurons, they are pseudounipolar.