Exam 1: Development and Back

What is the underlying cause of an atrial septal defect? What is the most common heart defect? What defect of the outflow tract results in the oxygen poor and oxygen rich blood mixing? What defect of the outflow tract results when helical spiraling does not occur during outflow tract septation?

-Atrial Septal Defect occurs when septum secundum is too short or too long or when septum primum and secundum fail to properly fuse at birth. This causes blood to continue to shunt from left atrium to right atrium. -The most common heart defect is Ventricular Septal Defects = Blood flows from LV to RV, increases workload on ventricles and lungs. -The birth defect that results in mixing of oxygen rich and oxygen poor blood is Persistant Truncus Arteriosus, single vessel exiting heart. -Transposition of the Great Vessels leads to spiraling of the conotruncal septum not occurring, this causes left ventricle to empty into the pulmonary circulation and the right ventricle to empty into the systemic circulation.

Know the two broad divisions of back musculature and their general functions.

1) Extrinsic muscles: These are superficial and intermediate layers. limb and respiration. Assist in elevating and depressing the ribs. Produce control to limbs movement (superficial). Thin muscles commonly designated as superficial respiratory muscles and are more likely proprioceptive rather than motor in function. (intermediate)

Know the two broad divisions of back musculature and their general functions.

2)Intrinsic muscles: Deeper and act on vertebral column as well as posture and movement. Also assist in movement of the trunk region. These muscles extend from the pelvis to the cranium and enclosed by deep fascia that attaches medially to the nuchal ligament.

What is caudal regression syndrome? What are key phenotypic traits of this defect in gastrulation?

A disorder that is the result of abnormal mesoderm development. Some characteristics of this disorder are flexion, inversion or lateral rotation of lower limbs, abnormal lumbar and sacral vertebrae, imperforate (not open) anus, agenesis of the kidney and urinary tract, agenesis of the internal reproductive organs. 1:100,000-2.5:10,000

What is a teratoma?

A teratoma is type of tumor that is composed of tissues from all 3 germ layers of development.

Describe ectopic pregnancy. What are possible sites of abnormal implantation?

An ectopic pregnancy is when implantation occurs at an improper site. These improper sites can include the uterine tube, the cervix, or the ovarian surface.

Trace the maturation of primary oocytes through the different types of follicles to ovulation. Following ovulation, the remaining follicle is called what? What is the role of this remnant?

At the primordial follicle stage, you have the primary oocyte stuck in meiosis 1 and enclosed in epithelium. There are around 7 million primordial follicles at around 5 months development, and around 400,000 at puberty. During each menstrual cycle 5-12 primordial follicles become primary follicles. A primary follicle develops the zona pellucida which is the glycoprotein coat that surrounds the primordial follicle, they also develop a thick layer of estrogen secreting cells called granulosa cells. At the secondary follicle, the Antrum pushes the oocyte to the side, the inner layer of cumulus oophorus cells form the corona radiata as well as the primary follicle finishes meiosis 1 and the process of forming the secondary oocyte and first polar begins. At the vesicular follicle the secondary oocyte and the 1st polar body are arrested in metaphase 2 of meiosis 2- this only happens with the dominant follicle the rest of the follicles undergo atresia. The remaining follicle is called the corpus luteum. The role of the remnant is to secrete estrogen and progesterone to maintain uterine lining.

Where does capacitation of sperm occur, and what does this process enable? What is the acrosome reaction?

Capacitation of sperm occurs in the ampulla of the oviduct and allows the sperm to penetrate the zona pellucida. The acrosome reaction is where the acrosome destabilizes and releases its enzymes, allowing the sperm to penetrate its way through the zona pellucida and fuse with the membrane of the oocyte.

Which region of the primitive streak contains the cardiac progenitor cells? When left and right heart fields unite, what structure is formed? There are 3 layers of the primitive heart tube - what are they? In the primitive heart tube there are swellings that can be attributed to future structures and chambers of the heart. Be able to identify these regions from the inflow to outflow regions and know what these regions form in the mature heart.

Cardiac progenitor cells are found in the cranial 1/3 of the primitive streak. When left and right heart fields combine the cardiac crescent forms. The three layers that form the primitive heart tube are Endocardial tubesàEndocardium, Mesodermà Myocardium, Cardiac jelly = Extracellular matrix of heart. Sinus venosus - Inflow/Vena Cava Primitive atrium - Forms both r/l atria Primitive ventricle - Forms left ventricle Bulbus cordis - Forms right ventricle Conotruncus - Portions of both ventricles, outflow tract/truncus arteriosus (aorta/pulmonary trunk) **Look at slide 25 of Development 3 to follow flow through or look above to track how the blood will flow through the primitive heart**

What are the major subdivisions within embryonic mesoderm and to what do they contribute? What are somites?

Cardiogenic mesoderm, paraxial mesoderm, intermediate mesoderm, lateral plate mesoderm. Paraxial mesoderm will form the muscles of the jaw, face and throat in the head and the vertebral column, muscles of the neck, body wall and limbs in the trunk region. Intermediate mesoderm forms the urogenital system like the kidneys, ureter, and etc., Lateral Plate mesoderm gives rise to the visceral peritoneum and some organs as well as gives rise to the parietal peritoneum and limbs. Cardiogenic mesoderm leads to the formation of the heart like the endocardium, myocardium and other parts of the heart. Somite's are block like groupings of mesoderm.

What structures arise from neural crest cells in the cranial region? What structures arise from neural crest from BOTH cranial and trunk regions? What structures arise from trunk neural crest?

Cranial - Connective tissue of the head and eye, muscles of the eye, part of the cornea, cartilages of the face and neck, bones of the face, head, ear, and neck, dermis and hypodermis of the face and neck, help separate the aorta from the pulmonary trunk in the developing heart, developing teeth. Cranial and Trunk - Schwann cells and glial cells of the PNS, melanocytes in the epidermis, and the pia mater and arachnoid layer of the brain and spinal cord meninges. Trunk - Chromaffin cells of the adrenal gland medulla, PNS dorsal root and chain ganglia, PNS ganglia that lie adjacent to the major branches of the descending abdominal aorta, enteric nervous system ganglia.

Know the different defects that arise from failure of closure in specific regions of the embryo. What portion of the vertebra is abnormal in spina bifida?

Craniorachischisis (LETHAL: brain and spinal cord remain open), Anencephaly (LETHAL: spinal region closed, cranial region did not), Spina Bifida. In Spina Bifida, the part of the vertebra that is affected is the spinous processdue to its failure to close or not close the right way.

During implantation, what two layers of cells form from the trophoblast, and what are their roles?

Cytotrophoblast - Line blastocyst cavity, secrete enzymes to break down endometrial lining, contribute to the developing placenta Syncytiotrophoblast - Help implant into the uterine lining, penetrate into the endometrium, pull the embryo into the uterine wall, and develop the entire blastocyst

Know the relative position of the 3 primary germ layers, their names, and the mature structures to which they give rise.

Endoderm - Deep to mesoderm and ectoderm, forms the gut and associated organs Mesoderm - Superficial to the endoderm and deep to the ectoderm, eventually will form 4 main subdivisions: Cardiogenic, Paraxial, Intermediate, and Lateral Plate mesoderm, will form most of the inner organs, heart, bones, muscles, etc. Ectoderm - Superficial to the mesoderm and endoderm, forms the skin and CNS

What two layers make up the bilaminar embryonic disc, and what will they form?

Epiblast (External layer) - Forms the embryonic structures and the amnion (water break sac) Hypoblast (Inner layer) - Forms the yolk sac which will house PGC's and form blood cells

What 5 prominences must fuse to form the face?

Frontonasal prominence, 2 maxillary prominences, and 2 mandibular prominences.

During week 3 of human development, the bilaminar disc becomes trilaminar. What is this process called? What marks the beginning of this process? What major axes of the embryo are established at this time?

Gastrulation. The thickening elongates to form the primitive streak, this marks the beginning of gastrulation. The major axes formed here are the Cranial-Caudal axes, the Medial-Lateral axes, and the Dorsal-Ventral axes.

What process leads to the correct spatial arrangement of the 4 developing heart chambers?

Heart looping https://www.youtube.com/watch?v=a0qyagIgBPw **draw out this process**

Know the two cell populations of the blastocyst, where are they found, and to what they give rise.

ICM/Embryoblast (ball of mass against the Zona Pellucida) ->Embryonic Trophoblast (inside the Zona Pellucida) ->Fetal part of placenta

In males and females PGCs must differentiate into different cell populations. Understand the timing of males PGC differentiation into spermatogonia and the subsequent mitotic and meiotic divisions that take place to create haploid spermatids. In females, understand the timing of PGC differentiation into oogonia and the subsequent mitotic and meiotic divisions that are required to make secondary oocytes.

In males the PGC's remain dormant from 6 weeks of development until puberty where they then undergo multiple rounds of mitosis and become spermatogonia, the spermatogonia then undergoes DNA synthesis to make a primary spermatocyte that is diploid, but has 4N chromosomes, the primary spermatocyte then undergoes meiosis 1 forming a secondary spermatocyte that is diploid 2N, it then undergoes meiosis 2 to form spermatids that are Haploid 1N. In females all of the PGC's undergo mitosis and differentiate to oogonia in the embryo, then at around 5 months of fetal development the oogonia undergo meiosis to form primary oocytes which are paused right before they complete meiosis 1, they will remain dormant in this stage until puberty. At puberty, every month a certain number of primary oocyte's will finish meiosis 1 and form a secondary oocyte and the first polar body, and pause before finishing meiosis 2, once the egg is fertilized the secondary oocyte and the first polar body will undergo meiosis 2 this will now form the definitive oocyte and three polar bodies.

Trapezious

Insertion: Clavicle, acromion process and spine of scapula. (on shoulder region near head) Innervated: by CNXI ( spinal accessory nerve) Origin: Superior nuchal line of occipital bones( base of the skull, top of the muscle) nuchal ligament, spinous processes of C7- T12 (all along the midline of the body) Actions: Elevates, superiorly rotates, retracts and depresses scapula (at the scapula) *Does everything for the scapula*

Be able to describe different types of orofacial clefts and know risk factors associated with clefts

Isolated cleft lip - maxillary and intermaxillary prominences fail to fuse. Isolated cleft palate - portions of maxillary prominence that form the palate fail to fuse at the midline. Both cleft lip & palate - intermaxillary and maxillary prominences fail to fuse in both regions. Risk factors are smoking, diabetes, epilepsy medications, and many unknown factors.

What are common features of hemifacial microsomia?

Lower structures of face and jaw are underdeveloped, usually on one side.

Describe the underlying cause of Treacher-Collins Syndrome. What are common physical features of Treacher-Collins Syndrome?

Mutations in a series of genes in the synthesis of ribosomal RNA is the cause. Physical features are underdeveloped cheek/jaw/chin, down slanting eyes, hearing loss due to middle ear defects, and absent/small outer ears.

Describe the defects that result from a failure of transverse folding.

Omphalocele - The digestive tract is still covered in a membrane. May have heart and other defects. Gastroschisis - The digestive tract is not covered, chance of inflammation/injury, feeding and absorption of nutrients disturbed. In both cases, a portion of the GI tract herniates outside of the anterior body wall.

Which pharyngeal arch mesoderm contributes to muscles of mastication (masseter, temporalis, pterygoids? Which contributes to the muscles of facial expression?

PA1 = mastication PA2 = facial expression

Know the cartilage and bones that are derived from each pharyngeal arch 1-4, and 6.

PA1 = palatopterygoquadrate cartilage contributes to the incus and the alisphenoid PA2 = Reichert's cartilage, stapes, the styloid process, the stylohyoid ligament PA3 = the greater cornu & the body of the hyoid bone PA4 and PA6 = thyroid, cuneiform, corniculate, arytenoid, and cricoid cartilages of the larynx

Which arterial structures do pharyngeal arch arteries 1-4 and 6 contribute to?

PAA1 -> portions of maxillary artery PAA2 -> portions of the stapedial artery PAA3 ->common carotid arteries; proximal internal carotid artery RPAA4 -> portions of right subclavian artery LPAA4 à the aortic arch LPAA6->ductus arteriosus (shunts blood from pulmonary trunk to aorta during development, closes at birth)

Describe a pharyngeal arch including the components/tissue types found within each pharyngeal arch?

Paired structures called pharyngeal arches give rise to structures of the face, jaw, and neck.

What are neural crest cells and how do they relate to the ectoderm of the neural tube?

Population of cells that arise during neurulation. They form from the pseudostratified columnar epithelium of the dorsal neural folds during closure of the neural tube, undergo EMT and move out of the neural tube tissue. They migrate to many other regions of the body, differentiates into a wide range of cell types, tissues and structures.

At Birth females have 1 million follicles each containing a that.

Primary oocyte; is paused in meiosis 1

What cell population is the precursor to the gametes? At what time in development and in what location are these cells "set-aside"? To where must they relocate/migrate in order to properly differentiate?

Primordial Germ Cells (PGC's). They are set aside at around 2 weeks of human development, they are set aside in the yolk sac. In order to properly differentiate they must reenter the embryo and migrate through the developing gut to the site where the gonads will develop; this occurs between 4-6 weeks of development.

When doe the secondary curvatures develop?

Secondary Structures begin to form when babies begin to walk

At what level of the vertebral column does the spinal cord end? What is this narrowed region called? Posterior to this level, what structure is a bundle of spinal nerve roots? What structure connects the spinal cord inferiorly to the coccyx?

a. L2/L3

What happens during spermiogenesis? What cellular components are found in each region of mature spermatozoa?

Spermiogenesis is the creation of mature spermatozoa and so the components that spermatids are missing are added to the spermatid. In the head of the sperm, there is the nucleus that is capped with an enzyme filled acrosome, the midpiece contains mitochondria which provide energy for motility, the tail is made up of microtubules arranged to form flagella for movement.

What is the driving mechanism behind the embryonic folding that occurs during week four of human development? Understand both cephalocaudal and transverse folding. What structures make the inner, outer, and middle of the "tube within a tube" body plan that results from embryonic folding?

The driving mechanism is that during this period the yolk sac grow more slowly than the embryo and amnion which will grow more quickly, this leads to elongation and "ballooning" of the disc. Cephalocaudal folding - Occurs between 21-24 days, occurs in cephalic and caudal regions of embryo, results in rapid growth of embryonic disc and amnion, no growth of the yolk sac, causes head and tail to fold on themselves. Transverse folding - Left and right sides of embryo curving toward ventral midline (LIKE A HUG), start to pinch off the yolk sac, fusing of sides of embryonic disc in midline, creates cylindrical embryo, ectoderm solely along exterior of embryo, endoderm confined to internal region of embryo; gut tube is created, yolk sac pinching off from most of ectoderm The outer tube is the ectoderm forming the epidermis of skin and CNS The inner tube is the Gut Endoderm Tube The middle is made up of Mesoderm

Know the details of the events of neurulation including: the first step in formation of the CNS, the type of epithelium found in the developing neural tube, describe convergent extension. What regions in the developing brain are visible as swellings in the neural plate? In order to close properly, the neural tube must bend in different locations - what are these locations called?

The first step in the formation of the CNS is neural induction which leads to the formation of the neural plate. The type of epithelium found here is the pseudostratified columnar epithelial cells. Convergent extension shapes the neural plate, it narrows in the transverse plane (looks skinnier) and elongates in the longitudinal plane (looks longer). The forebrain, midbrain, and hindbrain are seen as visible swellings in the neural plate. In order to close properly, the neural fold forms as lateral edges of neural plate elevate, leaving the midline low like a valley. The neural groove is found at the median hinge joint, just overlying the notochord, the neural plate also folds from the dorsolateral hinge points to allow the brain region neural folds to meet at the dorsal midline. Closure of the neural groove occurs at the dorsal midline. Starts closing in the trunk then closes going towards the ends.

Know how the muscular portions of the interatrial and interventricular septa form. Know how interactions between endocardial cells & cardiac jelly (cardiac cushions) help to form the atrioventricular septa and separate the single outflow tract into aorta and pulmonary trunk.

The muscular portions form due to increased proliferation of the myocardium in their respected positions, however they will not fully divide the chambers. Interactions between the endocardium and cardiac jelly will occur to fully divide the heart chambers. In the case with the endocardium and extracellular matrix interacting to form septa the endocardial cells, what first happens to form the septa is the myocardium secretes extracellular matrix which causes the endocardium to balloon outà Some endocardial cells in the region undergo EMT and enter into the extracellular matrixàThese cells then proliferate and then differentiate into connective tissue to create the septa

What are the septum primum and septum secundum? What is their function? What openings between the developing left and right atria are associated with each of these septa?

The septum primum and septum secundum are two partial septa found in the atria during development. They are not connected and allow right to left shunting of blood from the umbilicus bypassing the pulmonary circulation and entering into the systemic circulation. The opening between the atrium that remains is the foramen primum and foramen ovale.

What role/purpose do these curvatures have in the body?

These curvatures are used to support the weight of the body

Following zygote formation, the zygote goes through cleavages. Describe this process. At what cleavage and blastomere (the cells separated inside) number is the zygote considered a morula? Where is the zygote located during these cleavages? Describe compaction and know when it begins.

This process occurs after fertilization and is when the male and female pronuclei replicate DNA and the single cell divides but does not grow in the process. It is considered a morula at the 16-cell stage. The zygote is located in the ampulla and is travelling down towards the uterus as it divides. Compaction begins at the 8-cell stage allowing for maximum cell-cell contact between blastomeres. Compaction forces some cells to the center and some to the periphery, creating the centrally located inner cell mass/embryoblast and the peripherally located trophoblast.

What can cause ischemia in the spinal cord?

a. Lack of blood and oxygen and leads to muscle weakness and paralysis b. Fracture and or dislocation of vertebrae may damage spinal or medullary arteries c. Arterial stenosis in medullary arteries

Which structure is an important site for early blood cell formation, and serves to temporarily store the PGCs?

Yolk Sac

How many thoracic vertebrae are in the vertebral column? Which facet of the thoracic vertebra articulates with the head of a rib? Which with the tubercle of the rib?

a. 12 Thoracic vertebrae b. The superior costal facets articulate with the head of the rib c. T1-T10 have transverse costal facets, which articulate with tubercle of rib

What are the 4 curvatures of the vertebral column?

a. 4 curvatures of the vertebral column: i. Cervical ii. Thoracic iii. Lumbar iv. Sacral

How many cervical vertebrae are present in the vertebral column? Which two cervical vertebrae are atypical? Know the following about C1 & C2 vertebrae: Their commonly used "other" names, the movements they produce, special features of each that make them atypical.

a. 7 cervical vertebrae, C1 AND C2 are atypical b. C1= atlas i. Articulates with occipital condyles of occipital bone and C2 ii. Yes iii. No body or spinous process c. C2=Axis i. Articulates with atlas and C3 ii. NO iii. Dens is remnant of the missing atlas body iv. Has bifid spinous process

Know actions, origin, insertion & innervation of the trapezius

a. Actions: Elevates, superiorly rotates, retracts, and depresses scapula. b. Origin: Superior Nuchal Line of Occipital bone, Nuchal ligament spinous processes of of C7-T12 c. Insertion: Clavicle, acromion process of spine, spine of scapula Innervated by the accessory nerve

What role do anterior longitudinal ligaments and posterior longitudinal ligaments play in movement of the vertebral column?

a. Anterior longitudinal ligament i. Broad from sacrum to occipital bone ii. Stabilizes joints between vertebral bodies and limits extension of vertebral column b. Posterior Longitudinal Ligament i. Narrow inside vertebral column ii. Prevents hyperflexion and posterior disc herniation

What path (through which vessels) does blood follow as it drains from the vertebral column?

a. Basivertebral veinàInternal and external vertebral venous plexusesà Intervertebral veins through IV foramina into vertebral veins (neck) OR segmental veins (trunk)

What is an identifying feature of the cervical vertebrae (found on C2 -C7)? What feature is found on all cervical vertebrae (C1-C7), and what structures pass through this feature? What is another name for the C7 vertebra?

a. C1-C7 have the transverse foramen which contains vertebral arteries, veins, and sympathetic nerve plexuses b. C2-C7 has the bifid process c. C7= vertebra prominens

Which regions of the spinal cord show enlargements & why do these enlargements exist?

a. C4-T1 Cervical Enlargement b. L1-S3 Lumbosacral enlargement c. These enlargements exist due to the upper and lower limbs that require extensive innervation.

How many spinal nerves are there & how many are associated with each region of the spinal cord?

a. Conus medullaris, cauda equina, and filum terminal (anchor) b. 31 pair of spinal nerves i. 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal

There are 3 major classes of abnormal curvatures of the vertebral column. What are these 3 abnormalities? In which location and direction is the curvature abnormal in each category? What are causes/risk factors for development of these abnormal curvatures?

a. Dowager's hump=excessive Kyphosis i. caused by osteoporosis b. Hollow back=excessive lordosis i. Caused by weakened trunk muscles or pregnancy c. Scoliosis= Lateral rotation of vertebrae i. Leg length ii. Weaker back muscles iii. Vertebral defects

What embryonic structures contribute to the intervertebral discs? What 3 roles do the intervertebral discs play?

a. Embryonic structures= Paraxial mesoderm and Notochord b. Roles: i. Shock absorbers strong connection, and allow movement ii. Thicker in cervical and lumbar regions c. Nucleus Pulposus= gelatinous substance d. Annulus Fibrosus

Know the actions of the erector spinae, names of the lateral, intermediate & medial columns, and what the overlapping of the muscle fibers in these columns allows

a. Erector Spinae Muscles: i. Action= Chief extensor of vertebrae column 1. Bilaterally=extends vertebrae column and neck 2. Unilaterally= laterally flexes vertebral column ii. 3 Muscle groups 1. Spinalis Thoracis 2. Longissimus thoracis 3. Iliocostalis iii. Each column made of overlapping shorter muscle fibers=more variable flexion 1. Helps with stability 2. Localized actions 3. Allows segmentation of vascular and nerve supply

Know the arrangement of the nerves exiting the spinal cord: rootlets /roots/ganglion etc..

a. Exiting the spinal cord: i. Anterior rootletsàAnterior rootàAnterior ramus or posterior ramus

What movements are possible along the length of the vertebral column? What factors can limit the range of these movements? Which regions can rotate?

a. Flexion and extension b. Limits of range of movement: i. IV joint thickness and status ii. Shape of zygapophysial joints iii. Resistance of back muscles and ligaments iv. Rib attachment in thoracic region v. The size of tissue is vertebra column c. Thoracic region can rotate d. Lateral flexion is greatest in cervical and lumbar regions

Which feature of the venous return from the spinal cord offers an alternate pathway through which blood can return from the pelvis and abdominal regions? What else can happen as a result of this alternate pathway?

a. If the inferior vena cava is blocked, the vertebral venous plexuses can provide an alternate route for pelvis/ abdominal blood. b. However this is also a route for metastasis of cancer from abdominal or pelvic tumors.

What happens if the transverse ligament of the atlas ruptures?

a. If the transverse ligament of the atlas ruptures, then the spinal cord compresses between posterior arch and dens of Axis= Quadriplegia b. Or spinal cord/ dens press into medulla= death

What is a laminectomy? Other than to reveal the spinal cord in cadaver dissection, when would this procedure be performed?

a. Laminectomy= the surgical excision of one or more spinous processes and their supporting laminae in a region of the vertebral column b. We use this to relieve pressure on the spinal cord

Know action of latissimus dorsi, serratus posterior superior & inferior

a. Latissimus Dorsi= agonist of arm, adducts and medically rotates b. Serratus posterior superior= elevation of ribs for forced inspiration c. Serratus posterior inferior=depression of ribs during forced expiration

Which curvature is greater in females than in males? Which is greater in males?

a. Lumbar Curvature is greater in females b. Sacral curvature is greater in males

Understand the causes/effects of degenerative lumbar stenosis

a. Lumbar Stenosis= narrowing of vertebral canal b. Hereditary c. Age-Related degeneration i. IV discs flatten and become more brittle ii. Vertebral bodies more concave d. Spinal nerves compressed

Why is the body of the lumbar vertebra so large?

a. Lumbar vertebra is the primary weight bearing vertebra

Know which arteries supply the outer ring of the body of each vertebra. Know which arteries supply the spinal cord and which supply spinal nerves.

a. Periosteal Arteries supply the outer ring of vertebra b. Radicular arteries supply the spinal nerves c. Segmental medullary supply the spinal cord

What signals are associated with posterior roots of spinal nerves? Which signals are associated with anterior roots? What is the location of cell bodies of anterior versus posterior spinal nerve roots? What regions are supplied by posterior rami? Which ones by anterior rami?

a. Posterior root=afferent from skin, subcutaneous tissues, and viscera b. Anterior roots= efferent to skeletal muscle, presynaptic autonomic fibers c. Posterior root ganglion contains the cell bodies d. Axons going to the anterior roots have cell bodies I the anterior and lateral horns of spinal cord e. Spinal nerves almost immediately branch into posterior and anterior rami i. Posterior rami= skin and deep muscles of the back ii. Anterior rami=Limbs, truck, internal organs, anterior skin

Which are primary? Which are secondary?

a. Primary Curvatures= Thoracic and Sacral b. Secondary= Cervical and Lumbar

What are 2 functions of the vertebral column?

a. Protection of spinal cord and nerves b. Supports body weight superior to pelvis

Know action, origin, and insertion for: rhomboids

a. Rhomboid major and minor: i. Elevates, retracts, and inferiorly rotates scapula ii. Origin: 1. Minor is spinous process of C7-T1 2. Major is spinous process T2-T5 iii. Insertion Medical border of scapula

Which joint of the vertebral column transfers weight to the pelvic girdle? What structures pass through the posterior and anterior sacral foramina? How many vertebrae fuse to make the sacrum? Know which processes have fused to create the posterior crests on the sacrum.

a. Sacroiliac joint is where the weight is transferred to the pelvic girdle. b. Anterior and posterior sacral foramina allow passage of sacral spinal nerves and vessels c. 5 vertebra fuses to create the sacrum d. Fusion of vertebral processes create the posterior surface ridge i. Median sacral create from the spinous processes ii. Intermediate sacral crest from articular processes iii. Lateral Sacral crest from transverse processes

Know the names of the muscles of the suboccipital triangle, which vertebral joints they act on and what action they produce.

a. Suboccipital Triangle: i. Rectus Capitis= Both extend the head and neck ii. Obliquus Capitis=Both turn the to the same side iii. Both sets of muscles act on the atlas/axis

What structure passes through the vertebral foramen of vertebrae? What passes through the intervertebral foramen of vertebrae? What is the function of the spinous process and transverse process of a vertebra? Which portion of the vertebrae bears/supports body weight? Which two parts of a typical vertebra make up the vertebral arch? What function does the vertebral arch serve?

a. The spinal cord passes through the vertebral foramen b. Spinal artery of segmental artery, root of each spinal nerve, and communicating veins between the internal and external plexuses c. Spinous and Transverse processes functions are muscle attachment and movement d. Body of vertebrae bears the weight e. Vertebral arch= Pedicle and Lamina i. Protects the spinal cord

From vertebrae to spinal cord, what spaces and layers are found in the spinal cord? What is the supracristal plane? Why is this surface anatomy clinically important? Which layer is punctured during an epidural analgesia delivery? Which layer is punctured during CSF sampling?

a. Vertebrae i. Epidural space, filled with adipose and CT, real ii. Dura mater, long dural sac, and is continuous with cranial dural 1. Subdural space is a potential space iii. Arachnoid mater 1. Avascular 2. Subarachnoid space with CSF iv. Pia mater

What portions of the vertebrae are most commonly fractured? Why is vertebral dislocation less common in the thoracic and lumbar region?

a. Vertebral Dislocation is less common in the thoracic and lumbar region because the articular facets interlock b. More common in T11/T12 c. The body of the cervical vertebra

What branches from the aorta supply the spinal cord through their spinal artery branches? How many anterior spinal arteries and veins are there? How many posterior spinal arteries and veins are there?

a. Vertebral artery, ascending cervical artery, deep cervical artery b. 1 anterior spinal artery and 2 posterior spinal artery c. 3 anterior and posterior veins

What happens when an IV disc is herniated? What regions of the vertebral column are most commonly affected by disc herniation?

a. When an IV disc is herniated the nucleus pulposus exits and applies pressure to the spinal nerves i. Caused by a defect in the anulus fibrosus ii. Most common in L4/L5

What joints are found between articular facets? What type (classification) of joint are these?

a. Zygapophysial joint "facet joint" i. Synovial plane joint between articular facet ii. Permit gliding iii. Supplied by posterior rami of 2 spinal nerves iv. L2-L3 joint, supplied by L1 nerve and L2 nerve posterior rami v. Supraspinous ligaments connect adjacent spinous processes vi. Ligamentum flavum, extends between lamina of adjacent vertebra vii. Injury: 1. With age and osteoporosis or injury the zygapophysial joints experience pain along the skin and muscle supplied by the spinal nerves a. Denervation as treatment

How are zygapophysial joints innervated? How is rest of vertebral column innervated? Which nerves are affected when back pain occurs in periosteum, ligaments, etc? Which nerves are affected when the muscles and zygapophysial joints experience pain?

a. Zygapophysial joints are innervated by branches of posterior rami of 2 spinal nerves b. Rest of vertebral column innervated by recurrent meningeal branches of spinal nerves c. 5 common regions of back pain: i. Recurrent meningeal branches of spinal nerves 1. Fibroskeleton structures a. Periosteum, ligaments, anulus fibrosus of IV discs b. Meninges ii. Posterior rami of spinal nerves 1. Synovial joints (zygapophysial) 2. Muscles iii. Compression that leads to referred pain 1. Spinal nerves and nerve roots

in order for both epiblast cells and natural crest cells to migrate to a new location during embryonic development they must undergo the process of

epithelial to mesenchymal (?)

Name two specific mature cell types that are derived from the cranial neural crest.

cranial nerve ganglia, and muscles of the eye.

The Primary germ layer that gives rise to the nervous system, neural crest and the epidermis is the

ectoderm

Cleavage involves a series of _________ divisions and ________ in the overall size of the zygote

mitotic, no change

Know action, origin, and insertion for: Splenius capitis

i. Action: 1. Unilaterally= turns head same side 2. Bilaterally =extends head and neck ii. Origin=Nuchal ligament iii. Insertion=Occipital bone and mastoid process of temporal bone

1. Know action, origin, and insertion for: levator scapulae

i. Action: elevates and inferiorly rotates scapula ii. Origin: Transverse process of C1-C4 iii. Insertion=medial border of scapula

Which structure develops into a bilaminar disc?

inner cell mass

which layer within the embryo will develop into the urogenital system? (kindness,uretuers , bladder)

intermediate mesoderm

Origin of a muscle

muscle end attached to the bone that does not move when the muscle contracts, less moveable part

the trophoblast located in the _________develops an outer layer of cells called the __________

periphery of the blastocyst; synctrophoblast (?)

at the start of gastraution a long thickened region known as the _______________ ___________. forms on the surface of the epiblast

primitive streak

insertion of a muscle

the insertion of a muscle is the attachment of a muscle to a more movable part of the skeleton, as distinct from the origin