Mini 2 - week 3-6 Flashcards
Describe the regulation of F2,6BP in the cell.
cAMP -> PKA -> phosphorylates PFK2/FBP2 (dual enzyme) and stimulates its F2,6bisphosphatase activity which lowers F2,6BP. Glucagon or epinephrine (in skeletal muscle) stimulates this. In skeletal muscle, the PKA phosphorylation of PFK2/FBP2 is on a different side and cannot be inactivated.
What are various organelles doing at mitosis?
The ER and golgi vesiculate and reform at telophase. THe mitochondria, lysosomes, and peroxisomes remain intact.
What is the anatomical location and auscultation site of the mitral/bicuspid valve?
Medial left 3rd intercostal space. Auscultation site: Left midclavicular 5th intercostal space.
What is Zellweger syndrome?
A peroxisomal disorder where you are homozygous for a bad copy of the PTS receptor and so have empty peroxisomes. Many die in utero/at birth. Impaired neuronal migration/positioning, brain development.
What is fascia adherens?
Similar to macula adherens, anchors actin filaments, ribbon-like structure that stabilizes non-epithelial tissue.
Which steps in glycolysis generate energy?
G3P -> 1,3BPG (glyceraldehyde phosphate dehydrogenase) - makes an NADH 1,3 BPG -> 3PG (phosphoglycerate kinase) and PEP -> pyruvate (pyruvate kinase) generate an ATP. All these steps happen twice for one glucose.
What is pes planus?
Flat foot / fallen arches.
Where does the biceps femoris insert?
The head of the fibula.
What is the IC concentration of sodium?
15mM
What does the great cardiac vein run with?
The anterior interventricular artery/LAD.
What is the M-Cdk complex?
Cdk1-B
Describe skeletal muscle cross-bridge cycling.
Ca++-troponin (made of C, I, one other subunit) move tropomyosin on the actin, exposing the myosin binding sites.
When does heart development begin? describe it up until the formation of the primitive heart tube.
Week 3. Splanchnic mesoderm craniolateral to the above neural plate proliferates into a right and left tube. Apoptosis fuses the tubes (except at cranial and caudal ends) and forms an inner endocardial layer. middle cardiac jelly layer, and outer myocardial layer.
What’s a mixed nerve?
Contains both afferent and efferent fibers.
Describe the left ventricle.
Rough segment (trabeculae carnae), smooth segment (aortic vestibule), mitral/bicuspid valve (chordae tendinae, anterior and posterior papillary valves), a thicker wall.
What forms the epicardium?
Mesodermal cells that migrate from the developing liver.
What ganglia do CN III parasympathetic fibers synapse at?
Ciliary ganglion
How can lipids move in the cell?
1) lateral diffusion (SER/RER) 2) Translocate between leaflets 3) Vesicular transport 4) Movement through cytosol by attaching to lipid-transfer proteins (non-specific, pick up at lipid-rich areas, drop off at lipid-poor areas)
What is the effect of insulin?
Liver and muscle: upregulates glycolysis, glycogenesis, fat and protein synthesis, in muscle it also upregulates the GLUT4 transporter. Adipose: Upregulates glycolysis, upregulates adipocyte lipoprotein lipase which increases uptake of fatty acide from chylomicrons and VLDLs. Insulin dephosphorylates.
Describe Klinefelter’s Syndrome.
XXY. Developmental delay/learning disability/social maladjustment. Long limbs, tall, small testes. Reduced testosterone/sexual function. 55% have gynecomastia - risk of breast cancer. 15% are mosaics (ND in mitosis). Complications can be obesity, diabetes, pulmonary disease, problem with thyroid function. Androgens can virilize but may worsen gynecomastia.
How are nuclear lamins dealt with in mitosis?
They are phosphorylated and break down, then they are dephorphorylated at telophase. The assembling lamina binds condensing chromatin to the nuclear envelope vesicles - this drives envelope reassembly.
What innervates the anterior arm muscles?
The median nerve except for flexor carpi ulnarus and the 4-5 digits of flexor digitorum profundus, which are innervated by the ulnar nerve.
Describe ischemic cell injury.
Impairment of blood supply to the tissue results in lack of oxygen and loss of ATP generation by oxphos. Accumulated pyruvate converts to lactate, and the result is osmotic stress, activation of lysosomal enzymes, tissue acidification.
What is talipes equinovorus?
“clubfoot” - a congenital defect more common in boys, treated by braces/casts of surgery.
What is the rate limiting enzyme in cholesterol synthesis?
HMG-CoA reductase
What are the nerve roots of the sciatic nerve?
L4-S3.
What comprises the central nervous system?
Cortex, cerebellum, spinal cord. Virtually no connective tissue.
What do peroxisomes synthesize?
Plasmalogens (a major phospholipid class found in myelin) - H2O2 used in steps. Also participate in synthesis of bile acids from cholesterol. Bile acids needed to digest/absorb fats and fat soluble vitamins.
What establishes the embryo axes?
The primitive streak - cells condense in the posterior embryo up to about halfway. Determines situs solitus vs situs inversus.
Describe the aortic arch.
Begins and ends at level of sternal angle, arches over the left hilum superiorly and posterolaterally to the left, then descends inferiorly beside T4-T12 vertebrae (thoracic aorta). Branches are brachiocephalic trunk, left common carotid artery, left subclavian artery. Variations - can have retroesophageal right subclavian artery (no brachiocephalic trunk), esophagus compressed. Can also have double arch of the aorta/vascular ring anomaly. Can cause stridor and dysphagia.
In what conditions does the trachea deviate to the affected side?
Open pneumothorax, lung agenesis, pneumectomy
What is the IC concentration of calcium?
10^-7 - 10^-5 mM
What is thought to be the cause of sirenomelia?
The loss of mesoderm un the lumbar/sacral region.
What is the name of the anastomosis of arteries around the knee joint?
The genicular anastomosis (genicular branches of popliteal artery)
What makes up the cutaneous innervation to the buttocks?
The superior/middle/inferior cluneal nerves.
What are the superior mediastinal structures?
Arch of Azygous Phrenic nerve Vagus nerve Thoracic Duct Left recurrent laryngeal nerve Brachiocephalic veins (and SVC) Aortic Arch (and its 3 branches) Thymus Trachea Lymph nodes Esophagus (A PVT Left BATTLE)
Where is the apex of the heart?
Inferolateral part of LV, lies along midclavicular line at the left 5th intercostal level.
Describe elastic fibers.
Made of elastin core with fibrillin surrounding it. Made by fibroblasts and smooth muscle cells in arteries, also exists in many tissues. Marfan syndrome is a mutation in these fibers - cardiovascular symptoms life threatening.
What is the insertion of the obturator internus and the superior and inferior gemellus?
The trochanteric fossa.
Where do you find pseudostratified columnar epithelium?
In the trachea (respiratory epithelium, ciliated, has goblet cells). In the epididymis (stereocilia).
Describe unipolar (or pseudounipolar) neurons.
Single process that bifurcates close to the cell body, longer branch extends to the peripheral ending, other to the CNS. Spinal ganglia and most cranial ganglia are like this.
What are the nerve roots of the tibial nerve?
L4-S3.
What is tennis elbow and golfer’s elbow?
Tennis - lateral epicondylitis Golfer - medial epicondylitis
How can glands be classified?
Exocrine (retains connecting stalk) or endocrine. Simple or compound, tubular or acinar. Serous (purple/blue, secretes watery fluid usually with proteins) or mucous.
Where does the rectus femoris originate?
Anterior inferior ilia spine, and ilium superior to the acetabulum.
What kind of proteins are translated on ER ribosomes?
Secreted ones, membrane proteins, lysosomal/ER/golgi lumen proteins.
Describe the metaphase-to-anaphase checkpoint.
It checks that the chromosomes are complete, spindles attached. APC combines with cdc20, which activates it. (M-Cdk also helps activate it). Securin prevents separase from acting to cleave cohesins, but APC degrades securin via ubiquitination (at point of cell division it will also degrade Cyclin B)
What functions does stratified squamous epithelium have?
It protects the underlying tissues in areas subjected to abrasion.
Where do most ectopic pregnancies occur? In what kinds of women are they most commonly? To what level do these pregnancies develop? What is the triad?
In the ampullary region. Most common in women with prior surgery, endometriosis, PID (scarring can halt it). Most develop to 8-10 weeks. The triad of rupture/prerupture is amenorrhea, acute pain, vaginal bleeding.
What does the ilifemoral ligament do?
Limit hyperextension.
What is special about the tibialis anterior?
It is the most superficial muscle of the anterior compartment, and it also does foot inversion.
Describe the internal intercostal/oblique muscles.
Anterior and then a membrane. Go from sternum to angle of ribs. The neurovascular bundle is deep to them.
What does the SVC drain?
All structures superior to the diaphragm except the heart.
What are the three periods of embryonic development?
Week 1-2: germinal, 3-8: embryonic, 9 onwards: fetal
What is special about the plantaris?
It is not found in all people.
Describe the mechanism in E1 of PDH. Include cofactors.
Pyruvate reacts with TPP (thiamine pyrophosphate/B1) to form hydroxy-ethyl-TPP. A deficit of B1 results in Beri-beri, GI issues, and neurological findings.
What provides cutaneous innervation to the medial leg and bit of the foot?
The saphenous nerve (a branch of the femoral nerve).
What does inferior gluteal nerve injury result in?
Weakness of hip/thigh extension and lateral rotation. Weakness rising from a siting position and/or climbing stairs.
What is CoA-SH?
A combination of ADP, cysteamine. and panthenoic acid (B5). It acts as a carrier for high energy acyl bonds.
What is the Nernst Equation?
Vm = -61/z X log[i]/[o] Assumes T=37C
What are the nerve roots of the common fibular nerve? How does it travel?
L4-S2. It moves posteriorly to anteriorly by winding around the head and neck of the fibula - it is very superficial.
What is a pulmonary embolism?
Obstruction of the pulmonary artery by an embolus (usually from lower limb). Associated with acute respiratory distress, cor pulmonade (dilated RV), and pulmonary infarct. Symptoms are dyspnea, sharp chest pain, blood-tinged foamy sputum.
What is the normal reaction to the patellar reflex? What does it test?
The patellar nerve - should extend knee.
What’s the structure of skeletal muscle? What are the different units?
Myofibrils are the contractile elements - made of repeating sarcomere units. They are a bundle of myofilaments - actin + myosin. A muscle is made of fascicles, which are made of fiber/cells.
What is NRF2?
A transcription factor. It stimulates antioxidant genes by binding ARE in promoters and enhancers. In the absence of oxidative stress, it is kept in the cytosol and sent to the proteasome by KEAP1 but oxidants release KEAP1 from NRF2. The genes it regulates are for glutathione metabolism, NADPH production, genes for proteostasis proteins, genes for phase II drug metabolism.
Can the visceral pleura feel pain?
No
What kind of neurons are sensory./dorsal root ganglia?
Always pseudounipolar.
When does the amnion form?
By day 8. It’s made from amnioblasts, and will eventually surround the entire membrane.
Describe mtDNA.
Circular, double stranded, no histones/nucleosomes. 2-10 copies of genome per mitochondria. 37 genes (13 proteins, 2 rRNAs, 22 tRNAs). New mitochondria arise from the division of old mitochondria. Most mitoch proteins, however, are nuclear-encoded and post translationally transported with a mitochondrial targeting sequence. Sperm mitochondria are tagged in the testes with ubiquitin.
Describe the terminal sac period of lung maturation.
24 weeks - birth. The primitive alveoli develop, the epithelium thins and capillaries come in contact with it. The epithelium differentiates into type I pneumocytes (flat, sites of gaseous exchange) and type II pneumocytes (produce surfactant that decreases surface tension).
What is the name of the arterial arch on the plantar surface of the foot? What’s it made of?
The deep plantar arch. The lateral and medial plantar artery, both of which come from the posterior tibial artery. It anastomoses with the arcuate arch.
Describe the placenta septa.
By month 4-5, the decidua basalis is eroded to enlarge the intervillous space. Placenta septa are wedge shaped areas of decidua that project to the chorionic place - they separate the placenta into cotyledons.
What kind is joint is the hip joint? What are other names for it?
Aka the coxal/acetabular joint. It is a multi-axial, ball-and-socket type joint. Blood supply to this joint is the same as blood supply to the surrounfing skin and muscles.
What is the EC concentration of sodium?
150mM
Describe mast cells.
Wandering CT cells. Large basophilic membrane-bound granules containing histamine and heparin. Frequently found around blood vessels, has IgE receptors - at Ag exposure, binds, cross-links, activates adenylate cyclase -> entry of calcium triggers rapid granule exocytosis. It also releases prostaglandins and leukotrienes and they are also affected by eosinophil and neutrophil chemotactic factor (ECF and NCF).
What is the BcL2 family?
A family of enzymes that form pro and antiapoptotic heterodimers. BcLx is pro-apoptotic.
What is Familial Hypercholesteremia?
Almost always a defective LDL receptor or ApoB protein. Results in high serum cholesterol, might see yellow deposits of cholesterol-rich fat around the body. Heterozygotes (1/500) may develop cardiovascular disease prematurely (30-40) whereas homozygotes may have severe cardiovascular disease in childhood.
What direction does the patella most commonly dislocate?
Laterally.
Where do you auscultate the apex of the lung?
Superior to the medial 1/3 of the clavicle
What is PROM?
Premature rupture of the membrane (before contractions). Occurs in 10% of pregnancies.
What is the EC concentration of potassium?
5mM
How can damaged DNA affect the G1 checkpoint?
It activates ATM/ATR kinase which activates Chk1 and Chk2 which phosphorylate and activate p53, which regulates p51 (a Cdk inhibitor protein)
Describe the venous drainage of the heart.
Small, middle, great cardiac veins drain into the coronary sinus and tributaries. Tiny anterior cardiac veins drain into right atrium. There are also thebesian veins.
What is the Haber-Weiss reaction?
H2O2 + superoxide -> hydroxylradical + OH- + O2
What is myasthenia gravis?
Autoimmune disease destroying Ach receptors at the NMJ. Weakness, rapid fatigue of any skeletal muscles.
What makes up ground substance?
Glycosaminoglycans proteoglycans, multiadhesive glycoproteins.
Describe a double SVC.
The left anterior cardinal vein persists, the left brachiocephalic vein fails to develop. The coronary sinus is dilated.
What qualifies someone as being hypoxic?
A pulse ox under 95%.
What is the dorsal venous arch made of?
The small and great saphenous veins.
Describe peroxisome structure.
Small, membrane-enclosed, have >30 enzymes (peroxins). Spherical, smaller than mitochondria. Eukaryotes all have multiple cells with us, but not all cells have them. They are numerous in liver and kidney cells. Amount also varies based on need. They cannot be seen unless specifically stained for. Some species (but not humans) have electron dense inclusions in their peroxisomes seen on EM.
What are the 5 dilatations of the primitive heart tube, cranial to caudal?
Truncus ateriosis, bulbus cordis, ventricle, atrium, sinus venosus. Blood flow is caudal to cranial.
Where do the bronchial arteries arise from?
Right - thoracic aorta or 3rd posterior intercostal artery Left - thoracid aorta
What are Bouchard’s and Heberden’s nodes?
Bouchard’s is a bony bump at the PIPs and Heberden’s is one at the DIPs.
What is the meniscus of the knee?
A crescent shaped fibrocartilage pad that deepens the articular surface between the tibia and femur and provides shock absorption. There is a medial part firmly attached to the tibial collateral ligament and a lateral part not attached to the fibular one. The popliteus tendon also passes between the two menisci.
What degrades proteins?
The lysosome and proteasome.
What are the regulators of glucokinase?
High F6P promotes nuclear localization and binding to GKRP (glucokinase regulatory protein), wherease glucose promotes release and return to cytoplasm, therefore upregulating activity.
What are the 5 types of atrial septum defects? Are they cyanotic?
Acyanotic. Probe patent foramen ovale (25% of people, linked to migrains), Ostium secundum defect (incomplete fossa ovalis due to many possible reasons), Endocardial Cushion defect with ostium primum defect (often with mitral valve defects), Sinus venosus defect (close to SVC, high, often have pulmonary vein problem - might attach to RA and not LA) Common atrium/Cor Tricolae biventriculare (often associated with heterotaxy syndrome).
How does oligomycin work?
It blocks the ATPase in the ETC so the gradient gets very strong - too strong for the flow.
What’s special about phosphotidylserine?
It is the only negatively charged phospholipid, and it always is in the leaflet that faces the cytoplasm.
Where does the iliopsoas insert?
Lessert trochanter of femur.
What does through the adductor hiatus?
The femoral artery and vein move through it from anterior thigh to posterior knee (popliteal fossa), and change their names to the popliteal artery and vein.
What functions does simple cuboidal epithelium have?
Protection, secretion, absorption.
How do you image chromosomes?
1) obtain from metaphase cell (usually WBC) 2) Add phytohaemagluttinin (PHA) - culture for 3 days in incubator 3) Colchicine/colcemid inhibits spindle formation/stops division 4) Hypotonic saline + fixative (alcohol) to avoid enzyme breakdown of chromosomes - let drop fall, cell bursts 5) Digest with trypsin (protease) if banded karyotype is the aim 6) Stain with Giemsin
What is gliosis?
A nonspecific reactive change of the glia in response to CNS damage, proliferate to form scar tissue. Mostly this is astrocytes but sometimes also microglia and oligodendrocytes. They are a feature in MS, stroke. To see astrocytes in this, use GFAP stain - GFAP (glial fibrillary acidic protein) is an astrocyte intermediate filament.
Describe the left coronary artery.
Gives off Anterior IV Artery/LAD (supplies RV, LV, anterior 2/3 of IV septum, apex, anastomoses with post. IV branch of RCA at apex, gives off diagonal branch). Gives off Circumflex artery (supplies LA, LV, anastomoses with RCA at coronary sulcus), which gives off Left Marginal artery (supplies LV, anastomoses at IV branches).
What is the difference between the main primary bronchi?
Right is more vertical and has a larger lumen.
Describe the second week of embryo development.
The uteroplacental circulation is established. The epiblast forms the extraembryonic mesodermal layer (cavities formed). The hypoblast divides, exocoelomic cysts form. Extraembryonic cavity now called chorionic cavity. Extraembryonic mesoderm called chorionic plate. The cytotrophoblast cells, surrounded by syncytia, proliferate and develop primary villi.
What happens if you have an absence of the hepatic segment of the IVC?
Usually associated with heart malformations. The blood from the caudal parts just drains into the azygos and hemiazygos veins and enters via the SVC.
What is special about the obturator extremis?
It laterally rotates the thigh - the other medial thigh muscles medially rotate/adduct the thigh.
What is a contiguous gene disorder?
A deletion/duplication in part of a chromosome - is inherited like a gene disorder but it is not a single gene issue.
What does the sinus horn of the embryo become?
By week 4/5 there is left to right shunting of blood - the right sinus horn grows and pushes it self into the right atrium. The remnant of the left sinus horn forms the oblique vein of the left atrium and the coronary sinus.
How does the TCA cycle contribute to gluconeogenesis?
It feeds pyruvate and amino acids towards it by increasing oxaloacetate concentration.
What provides cutaneous innervation between the first and second toes dorsally?
The deep fibular nerve.
What is synapsis?
The process of homologous chromosomes associating for recombination/
What ganglia do CN VII parasympathetic fibers synapse at?
Pterygopalatine and submandibular ganglion
What is the adductor canal?
A fascial compartment posterior to sartorius thorugh which travel the femoral artery/vein, nerve to vastus medialis, saphenous nerve.
What do the subcardinal veins form?
Portion of IVC, renal veins, gonadal veins.
What are the types of glucose transporters?
GLUT1 (basal uptake) GLUT2 (liver - highest Km) GLUT3 (brain) GLUT4 (muscle and fat tissue, insulin responsive)
How are citrate synthase, isocitrate dehydrogenase, and alpha-KG dehydrogenase regulated?
By product inhibition, energy state/need, and NAD+ supply. alpha-KG dehydrogenase is regulated exactly like PDH, theyre very similar.
Where do the posterior intercostal arteries originate from?
1-2nd from the subclavian - costocervical trunk. 3-11th from the thoracic/descending aorta.
What is the action of the lumbricals? What innervates them?
Flex the metacarpophalangeal joints, extend the interphalangeal joints of digits 2-5. 1+2 - the median nerve (medial and lateral branches) 3+4 - the deep branch of the ulnar nerve
What is the action of the lateral leg muscles? What is the blood supply/innervation?
Eversion and weak plantarflexion. The perforating branches of the fibial and posterior tibial arteries and veins. The superficial fiibular nerve.
What are the free radicals, in increasing order of harmfulness?
H2O2 (hydrogen peroxide), O2- (superoxide), OH (hydroxyl radical).
What organelles are localized to the perikaryon/soma?
Most of the ER (but SER can extend sometimes) and all of the golgi.
What is the crista terminalis called externally?
The sulcus terminalis.
What conditions is oxidative stress linked to? ROSs?
Aging, neurodegenerative disorders, atherosclerosis through LDL oxidation. ROS is required for normal muscle function but high amounts are associated with muscle fatigue.
What is the action and origin of the gastrocnemius?
Plantarflexion when knee is extended, flexes leg at knee. Origin: the lateral and medial condyles of the femur.
Describe postductal coarctation/stenosis of the aorta.
Most common distal to the left subclavian artery. Results in dilated torturous arteries, rib notching on the 3-9th rib inferior margins, lowered blood pressure in lower limb and higher in upper limb. Collateral circulation: aortic arch -> subclavian -> internal thoracic -> anterior intercostal -> posterior intercostals -> thoracic aorta. Coarctation can be pre or postductal and with or without patent ductus arteriosus.
How is pyruvate converted to oxaloacetate?
Through pyruvate carboxylase. Requires the hydrolysis of ATP, and needs biotin (B7) as a cofactor.
What innervates adductor pollicis?
The deep branch of the ulnar nerve.
Describe cardiac muscle.
Only in the heart, striated uninuclear, less organized actin/myosin arrangement. Lots of mitochondria, fatty acids, lipofuscin granules often found in long-lived cells. Have intercalate discs (gap junctions, desmosomes/macula adherens, fascia adherens). We are born with a set number of cardiomyocytes, less than half of which get turned over in a lifetime.
Can cardiac muscle regenerate?
Barely. Defects are replaced by CT growth and proliferating fibroblasts.
Describe heart conduction.
SA node is the pacemaker -> AV node (through AV bundle and right and left bundle branches) -> papillary muscles/ventricular walls on each side of IVS.
What are myoepithelial cells?
Contractile non-muscle cells. Keratin IFs, similar contraction to smooth muscle.Possess desmin. Exist in certain glands and share basal laminae of secretory and duct cells, express secretory material from glandular epithelium out of gland into ducts. In lacrimal glands in response to Ach and in mammary glands in response to oxytocin.
What comprises a peripheral nerve?
axon + Schwann cells + CT + blood vessels
What’s more lateral, the extensor carpi radialis longus or brevis?
Longus is more lateral.
What is HSP70?
A chaperone protein that assists in folding. It is ATP-binding, recognizes a series of hydrophobic amino acids, binds, waits for a ‘clock’ to hydrolyze ATP - this gives time for the rest of the protein to be made.
What provides cutaneous innervation to the dorsum of the foot (except for the skin between the first and second toes)?
The superficial fibular nerve.
What is the action of catalase?
It converts hydrogen peroxide into two waters.
Which steps in glycolysis require ATP?
Glucose -> G6P (glucokinase/hexokinase), and F6P into F1,6BP (PFK1)
Where do you do a pericardiocentesis?
Left 5-6th intercostal space near the sternum at an infrasternal angle.
What do growth factors do?
They stimulate the PI3K pathway which stimulates TOR and upregulates all translation.
Describe synapses.
Mostly chemical but can be electrical via gap junctions - often where the fastest response in needed e.g. defensive reflexes. Mostly axodendritic but can be other.
What is the general action of the anterior thigh?
Extension at the knee, flexion at the thigh.
What are cervical ribs?
0.5-2% of the population, can be uni or bilateral. They are associated in thoracic outlet syndrome - compression of neurovascular structures exiting/entering the superior thoracic aperture.
What do the 4th aortic arch arteries become?
Left becomes arch of aorta (also formed from partitioning of outflow tract), Right becomes proximal right subclavian (distal right subclavian comes from 7th intersegmental artery).
Describe ventricle formation, including the septum.
Rough part from primitive ventricle, smooth part from bulbus cordis. The muscular IVS forms in end of week 4 from myocardium but halts in week 7 and does not fuse with the endocardial cushion (IV foramen). The membranous IVS is an extension of tissue from the right side of the endocardial cushion as well as tissue from the aorticopulmonary septum (neural crest cells), as outflow tract is being partitioned.
Which cells are professional phagocytes?
Neutrophils and macrophages.
Where is the base of the heart?
Mainly the LA, some RA. T5-T8 level, overlays esophagus and thoracic aorta. Receives pulmonary veins on LA part, SVC/IVC on RA part.
How do the common iliac arteries form embryologically?
They form from the 5th intersegmental arteries 5ISA. These also give rise to the external iliac and proximal iliac arteries.
What do the 6th aortic arch arteries become?
Right forms right pulmonary artery, Left forms ductus arteriosus (begins ligamentum arteriosum after birth) and some of left pulmonary artery.
What is hemoptysis?
Spitting blood. If it’s from the lungs, 95% its from the bronchial vessels.
What is the action of the piriformis?
It laterally rotates an extended thigh, abducts a flexed thigh. It exits through the greater sciatic foramen and so do the superior and inferior gluteal artery.
What kind of gland is the pancreas?
Both endo and exocrine.
How many ATPs are made from TCA? DIrectly and indirectly.
20 (2GTP, 6NADH, 2FADH2)
What innervates the popliteus? What is its action?
The tibial nerve. Weak knee flexion / unlocks knee joint by rotating femur 5 degrees laterally on fixed tibia (or tibia 5 degrees medially on fixed femur).
Describe GAGs.
Long straight repeating disaccharide units, mostly sulfated/carbonyls (negative charge). They attract cations which attract water, which hydrates the gel and makes it able to resist compressive force.
What screening test values go up, down, and stay the same with increased disease prevalence?
Up: accuracy, PPV Down: NPV LR+ and LR- stay the same.
What’s the A-band of a sarcomere?
The overlap of myosin and actin.
What ganglia do CN X parasympathetic fibers synapse at?
Ganglia near the innergated organ. Vagus nerve is the “wanderer” - travels as far as the left colic flexure.
What is the general blood supply and innervation of the anterior thigh?
Femoreal artery/vein/nerve (L2, L3, L4)
Describe the paths of the phrenic nerves.
Anterior to the lung roots. Right descends along right side of SVC/IVC and pierces diaphragm near caval opening. Left descends lateral to left subclavian artery, course superficial to left atrium and ventricle, pierces diaphragm to left of pericardium.
What do the 2nd aortic arch arteries become?
Dorsal end forms hyoid arteries from which arise stapedial arteries. These connect the branches of the future internal and external carotid arteries.
What is multiple sclerosis?
A CNS autoimmune demyelinating disease.
What is cohesin?
It is an enzyme that holds sister chromtids together.
What are muscle spindles?
CT capsule surrounding a fluid-filled space that has a few thin, non striated fibers dense with nuclei called intrafusal fibers. Several sensory axons wrap around these fibers. The change in length of the surrounding striated extrafusal fibers are detected by the muscle spindles and the information is relayed to the spinal cord.
What proteins are involved in vesicle budding?
Clathrin (RME), COPI, COPII induce curve in the membrane, dynamin cuts the stalk.
Where do the rough and smooth parts of the left atrium develop from embryologically?
A single pulmonary vein grows out of the primitive atrium (eventually splits into 4), the rough part are the cells that outgrew to do this, the smooth is the cells that outgrew but returned.
What is a nerve fiber vs a nerve?
A nerve fiber is an axon or dendrite, a nerve is a collection of fibers (mostly axons and mostly myelinated).
What is the general autonomic visceral motor pathway?
2 neuron pathway. Preganglionic neuron cell body in lateral horn, postganglionic varies. Generally the preganglionic axon is myelinated and the postganglionic is unmyelinated.
Name all the monosomies compatible with life.
Just X. >99% die in utero.
What is a P value?
The probability a test statistic could have occurred by chance. It needs to be less than alpha to conclude statistical significance. The smaller a P value, the greater difference between groups, smaller probability of making a type I error, greater the significance of the finding.
Describe pulmonary circulation.
Pulmonary arteries turn into lobar arteries which turn into tertiary segmental arteries (and segmental branches) which supply a single bronchopulmonary segment. 2 pulmonary veins drain into a single lung, run independent of arteries and bronchi. They are intersegmental.
Where does shingles lie dormant?
In the dorsal root ganglion.
What are the hypothenar muscles and what innervates them?
Abductor digiti minimi Opponens digiti minimi Flexor digiti minimi brevis The deep branch of the ulnar nerve.
What are myoepithelial cells?
Cells between gland cells and their basal lamina. When innervated, they cause secretion out of the gland. They are ‘true’ epithelial cells, with keratin intermediate filaments. They are found in sweat, lacrimal, salivary, and mammary glands.
What happens if you damage the median nerve at the wrist?
Thenar damage, loss of thumb opposition, weakened abduction and flexion, “Ape hand”.
What are PNS satellite cells?
The primary glia - cover the surface of the soma in sensory and autonomic ganglia. Thought to play a similar role to astrocytes, supply nutrients, some protective/structural functions.
What functions does transitional epithelium have?
Expansion to hold increased volume and protect against hte hypertonic and cytotoxic effect of urine.
What is variable expressivity?
Where there is a difference in severity or age of onset for the same genotype. Usually in dominant illnesses, there’s no no symptoms just variation.
What is patent ductus arteriosus?
A connection between the aortic arch and the pulmonary trunk. It can close spontaneously by day 3 in 60% of normal term neonates - give preemies NSAIDs - block E1 prostaglandins that keep it open. Can be ligated with relatively low risk.
What do the sympathetic fiber axons from T1-T4 do?
Innervate the heart and lungs. (Cardiopulmonary splanchnic nerves).
Describe the venous system of the embryo.
3 paired veins - Umbilical (right and left, drain poorly oxygenated blood from the yolk sac), Vitelline (right and left, return oxygenated blood from the placenta), Cardinal (anterior, posterior, subcardinal, supracardinal, drain poorly oxygenated blood from the embryo).
What is a primary lysosome?
A “virgin” lysosome, it buds off from the golgi before receiving any material to be digested.
What causes hay fever?
Histamines by nasal mucosa mast cells.
What are the four types of junctional complexes in the lateral domain of epithelia?
Zonula occludens/tight junctions, zonula adherens, macula adherens/desmosomes/spot adhesion, gap junctions.
How does CO work in regards to the ETC?
It binds heme on complex IV of the ETC but the initial symptons are not because of that, they’re because of the loss in O2 carrying capacity.
What makes up the lumbar nerve plexus?
The ventral rami of L1-L4.
What is the threshold for action potentials?
About 15mV higher than the resting membrane potential?
Desribe reticular lamina.
It is secreted by CT fibroblasts, and attached to the basal lamina below it, with collagen VII (anchoring fibrils) and III (reticular fibrils).
Basal lamina and reticular lamina make up the basement membrane, which can be seem in LM.
What is Dupuytren’s Contracture?
The palmar fascia of the medial hand thickens, pulling the fourth digit in flexed.
What is the general action of the posterior leg muscles? What are their blood supply/innervation?
Plantarflexion. The posterior tibial, fibular, popliteal arteries/veins. The tibial nerve (L4-S3).
What do the sympathetic fiber axons from T12 do?
Form the least splanchnic nerve -> innervates inferior mesenteric ganglia.
Describe epineurium.
Dense irregular CT (fascia), mainly type I collagen, continues down to fill spaces between bundles, surrounds entire nerves.
Describe dark G-bands.
Later replication, fewer transcriptionally active genes, probably shorter loop structures, more condensed chromatin structure, higher in A-T base pairs, stain dark with quinacrine (q-bands) and are light with R-banding.
What is the Fenton reaction?
A way that iron catalizes hydroxyl radical formation H2O2 + Fe2+ -> OHradical + OH- + Fe3+ Fun fact: iron can also be reduced by superoxide
Describe the general mechanism of fatty acid synthesis.
Occurs in liver when there is sufficient carb influx to raise acetyl CoA concentrations beyond local energy needs. AcCoA converted into FAs which are then added to glycerol phosphate and become VLDLs. This process gets its ATP from oxphos, and its NADPH from HMP/PPP (which can also make ribose via ribose-5-phosphate).
How does the foregut opening form?
The oropharyngeal membrane (endoderm+ectoderm) ruptures in week 4 to form it.
What are A type chromosomes?
Large, mear metacentric. 1-3.
What are uncouplers? Name some.
Small, hydrophobic acids that can just diffuse in. THey bring H+s with them into the mitochondrial matrix, thereby reducing the gradient and turning off ATP synthesis. 2,4 dinitrophenol, FCCP, CCCP, acetylsalicylate (aspirin) at high concentrations, UCP1/thermogenin in brown fat of hibernating animals.
How can you make more peroxisomes?
By fission or de novo (upregulate translation of PTS receptor, upregulate translation of peroxins all with PTS)
What muscles are affected by ulnar nerve damage at the elbow?
The medial 1/2 of the flexor digitorum profundus. Cannot flex the DIPs of 4-5. Claw becomes less prominent “ulnar paradox”.
What happens once the sperm enters?
The sperm and egg PM break down and bind at the fusion area. The sperm cell membrane enters the oocyte cytoplasm and its mitochondria and tail degenerate. The sperm nucleus forms the male pronucleus, the secondary oocyte finishes meiosis II, and the two pronucleii fuse into a zygote.
What are the inheritances of different loss of function mutations?
Compensation or 1/2 the product is enough - recessive inheritance. 1/2 the amount of product is not enough (haploinsufficiency) is dominant inheritance.
What is reduced penetrance inheritance?
When someone has the genotype but doesn’t show symptoms (usually in dominant inheritance).
What makes up the femoral triangle?
The inguinal ligament, the sartorius, and the adductor longus.
What does it mean that the EC and IC are electroneutral?
They each have the same number of positive and negative ions?
What is allelic heterogeneity?
Different alleles at the same locus/gene. Symptoms may be the same or different.
Where do you find stratified squamous epithelium?
linings of the esophagus, mouth, vagina, urethra, anus. Keratinized is only found in the epithelium.
Describe leg lymph drainage.
It follows the route of the great saphenous vein then goes to the superficial inguinal LNs, then the deep inguinal, external iliac, and lumbar/aortal.
What is stage 1 hypertension?
For someone 18-60/diabetic/renal disease: systolic 140-149, diastoic 90-99 For someone over 60: 150-159 systolic
What is Patellofemoral pain syndrome?
“Runner’s Knee”. It is pain/inflammation deep to the patella due to abnormal gliding over the femur surface. Causes: excessive downhill running, direct trauma to patella, weak vastus medialis, osteoarthritis.
What is the anatomical location and auscultation site of the tricuspid valve?
Medial aspect of right 5th costal cartilage. Auscultation site: Left parasternal 5th intercostal space
What are shin splints?
Small tears in the periosteum (dense layer of vascular CT) at the attachment of the anterior compartment muscles - commonly tibialis anterior. Treat with rest.
What innervates the mediastinal pleura?
The phrenic nerve (anterior rami C3-C5). It also innervates the pericardium (pain referred to root of the shoulder) and central diaphragm.
What is “trigger finger”?
Flexor tendinitis - the tendom becomes inflames and swells too much to pass back into the sheath, locking the finger in a flexed position. Common in diabetics and people with rheumatoid arthritis.
How does the BCV develop?
Develops from the anastomoses of the left and right anterior cardinal veins when the caudal left anterior cardinal vein degenerates.
When does the embryo embedded fully in the endometrium?
Day 9-10. The defect is closed by a fibrin coagulum plug.
What do the 3rd aortic arch arteries become?
The common carotid arteries - the internal also comes from the dorsal aortae.
What do the umbilical veins form?
Ligamentum teres. They degenerate early in fetal life.
What is inside the femoral triangle?
The femoral nerve, artery, vein, an empty space, and the lacunar ligament. NAVEL
What are Nissl bodies?
Neuron specific RER + free ribosome aggregations due to the neuron’s high synthetic activity. They stain basophilic.
How is the transverse pericardial sinus formed?
The dorsal mesoderm differentiates and provides structural support to the posterior body wall. When the heart gets stronger, it degenerates and leaves behind the transverse pericardial sinus.
What does rib 2 have that typical ribs do not?
A serratus anterior tuberosity.
What are the ligaments of the knee?
Patellar (continuation of quadriceps femoris tendon to the tibial tuberosity). Tibial and Fibular collateral. Anterior and posterior cruciate.
Describe notochord formation.
It forms as the endoderm cells differentiate and push into the mesoderm and fuse, detaching from the underlying endoderm. Failure can lead to a spontaneous abortion. It degenerates as vertebrae form, the remnants remain as nuclei pulposi.
Which anterior arm muscles originate at the medial epicondyle?
Pronator teres Flexor carpi radialis Palmaris longus Flexor digitorum superficialis Flexor carpi ulnaris
What are the three layers of the maternal part of the placenta and where does it differentiate from?
The endometrium. The decidua is the functional layer that separates from the uterus in childbirth. Decidua basalis Decidua capsularis (overlying, superficial part of decidua) Decidua parietalis
What is a screening test for?
To identify a subset of people likely to have the disease - and to therefore increase efficientc of the diagnosis. Early detection, diagnosis, treatment.
What are the medial and lateral and inferior borders of the popliteal fossa?
Lateral - biceps femoris Medial - semimembranosus/semitendinosus Inferior - Heads of the gastrocnemius
Which step in the TCA cycle creates FADH2?
Succinate -> Fumarate via succinic dehydrogenase.
Where do the flexor/extensor ulnaris and radialis originate?
At the base of the 5th and 2nd metacarpals respectively.
What’s the Z-line of a sarcomere?
Connected to the sarcolemma.
How can the RER exchange with the SER?
Through diffusion - they are continuous.
What are dendritic spines?
Projections on dendrites, each is the site of a synapse. Highly plastic, morphology depends on actin, reduces with age, poor nutritition, retardation.
What is sperm capacitation?
The glycoprotein coat is removed from the acrosomal region plasma membrane. Only capacitated sperm can cross the corona radiata. The zona pellucida helps in cell binding - maintains binding and induces the acrosomal reaction. The acrosomal enzymes (acrosin, esterase, neuraminidase), are released, which lets sperm penetrate.
What is the cytoskeleton of neurons made of?
Actin.
Describe microglia.
The main form of CNS active defense. They are descended from monocytes, migratory, pretty evenly distributed through white and grey matter.
What is the transverse sinus of the pericardium?
Passage between the ascending aorta and the pulmonary trunk. A ligature is passed through this to clamp ascending aorta and pulmonary trunk during surgery.
How are prostaglandins synthesized?
PKC (Galphaq) stimulates MAPKwhich activates PLA2. PLA2 releases arachidonic acid, which is converted to prostaglandins and leukotrienes.
What are amniotic bands?
Pieces/tears of amnion that can encircle part of the fetus and result in limb constriction, amputation, craniofacial deformities.
Describe the G1 checkpoint.
Needs the G1-Cdk, G1/S-Cdk, S-Cdk. They hyperphosphorylate pRb - it lets go of E2F which becomes active and affects transcription to go through the checkpoint.
What does the nerve to obturator internus innervate?
The obturator internus and the superior gemellus.
What evidence do we have that neurons express a trophic effect on the cell with which they synapse?
If an axon is severed and the neuron degenrates and cannot regenerate, the post-synaptic cell atrophies and degenerates as well.
Describe C fibers.
1um thick, unmyelinated, 0.5-2m/s (avg 1m/s). Skin afferent fibers from nociceptors and sympathetic postganglianic efferent fibers.
What does the azygous vein drain?
Back, mediastinal, viscera, thoracoabdominal wall.
What are gliomas?
Glial tumours. Most common is astrocytoma but can also have oligodendrocytoma and ependyoma. Neuronal tumours are rare but exist.
What does the pubofemoral ligament do?
Prevents hyperabduction.
What can plantar fasciitis lead to?
A calcaneal/heel spur.
What is the normal delta G of glycolysis and what is it in the cell?
-7.3 kcal/mol and -13 kcal/mol due to ATP.
What is endothoracic fascia?
The glue holding the parietal pleura to the thoracic wall. It is made of LCT, and above the 1st rib-C7 transverse process it is thickened to cover the lung apex (Sibson’s fascia).
Describe partitioning of the outflow tract.
Cranial version of bulbus cordis tapers into conus cordis and merges with the truncus arteriosus. The neural crest cells migrate and incade the truncal and bulbar ridges, which twist around each other and grow in a spiral fashion to form aorticopulmonary septum. The septum divides the truncus arteriosus and conus cordis into the pulmonary tract, ventral aorta, aortic sac. The aortic sac forms right and left horns to form brachiocephalic trunk, ascending aorta, proximal aortic arch.
What is the purpose of the Na+/K+ pump?
K+ leaks out of the cell and Na+ leaks in. THe pump exports 3 Na+s and imports K+s to maintain the gradients. This pump takes up 2/3 of the body’s energy.
What ganglia do CN IX parasympathetic fibers synapse at?
Otic ganglion
Describe transposition of great vessels.
A partitioning of outflow tract defect. Septum is straight and now spiral, 3:1 males:females, results in aorta being attached to right ventricle and pulmonary trunk to left. Most infants die in first few days, extremely cyanotic. Incompatible with life unless there’s an accompanying shunt (VSD, patent foramen ovale, patent ductus arteriosus). Give baby prostaglandins to keep ductus arteriosus open. Increased risk associated with rubella, other viruses in pregnancy.
Describe the process of PNS neural regeneration.
2 weeks post injury - less Nissl substance (RER autophagy), nucleus moves off to one side, debris removed by macrophages. 3 weeks - Schwann cells proliferate and form Schwann Tube, end of cut axon forms sprouts, one finds Schwann tube and begins elongating through it (others degenerate). In the meanwhile, the muscle is atrophying. 3 months - if successful, axons sprout through tube and grow 3-4mm/day, reaches postsynaptic membrane and establishes contact. Can be blocked by scar tissue, if its a mixed nerves you can get sensory fibers growing to a muscle which will do nothing.
How does neurulation begin?
The notochord induces the ectoderm to thicken and form the neural plate. By the end of week 3, lateral edges of plate elevate - form folds/groove.
What is special about the sartorius?
It flexes at the knee unlike most anterior thigh muscles - it also produces the cross legged position.
When does the primitive streak disappear? What if it doesn’t?
Around week 4, it apoptoses as gastrulation nears. If something goes wrong, a sacrococcygeal teratoma can form. This is the most common newborn tumour, mostly not malignant, 80% in females.
What is the action of superoxide dismutase?
It converts a superoxide to O2 and water.
What kind of molecule is myelin?
A lipoprotein.
What are F type chromosomes?
Small metacentric. 19-20.
What is the general action of the medial thigh?
Adduction at the hip.
Describe ventricular septal defects.
Acyanotic. More common in males. Membranous type (issue with muscle layer) is 70%, associated with defects in the AP septum. The muscular type is often swiss cheese. Large VSDs can cause excessive pulmonary blood flow - hypertension, cardiac failure in infanct.
What does the coronary sinus run with?
The circumflex artery.
Describe the right ventricle.
Rough segment (trabeculae carnae), smooth segment (conus arteriosus/infundibulum), tricuspid valve (chordae tendinae, anterior/posterior/septal papillary muscles), septomarginal trabeculae/moderator band (runs from base of anterior papillary muscle to IV septum, carries right branch of AV node).
What can inhibit the complexes needed for the G1 checkpoint?
TGFbeta (epithelial cells), DNA damage, contact inhibition, cAMP (fibroblasts, smooth muscle cells).
What do the 1st aortic arch arteries become?
Mostly degenerates, but in adults become maxillary arteries.
Describe the mechanism of HIF.
Prolyl Hydroxylase is active in the presence of oxygen, where it hydroxylates HIF and it is degraded. In the absence of oxygen, it cannot do that and HIFa goes ot the nucleus and meets HIFb, where it acts as a transcription factor and increases the transcription of a bunch of stuff.
What makes up the right and left borders of the heart?
Right: RA, SVC, IVC Left: LV (mainly) and left auricle
How do cells maintain a high NADPH:NADP+ ratio?
1) G6P dehydrogenase (HMP/PPP) 2) Malic enzyme converting malate to pyruvate 3) Mitochondrial transhydrogenase that uses the proton gradient Erythrocytes depend on G6P dehydrogenase - if deficiency, can result in hemolytic anemia during oxidative stress. Lots of people have a partial deficiency - Fava beans and certain drugs can trigger this happening.
What are the other names for complexes I-V?
I: NADH dehydrogenase II: Succinate dehydrogenase III: Cytochrome reductase / Cyt bc1 IV: Cytochrome oxidase V: ATP synthase
What exits through the lesser sciatic foramen?
The tendon of the obturator internus.
How do ribs 10-12 differ from typical ribs?
One facet on the head. 11 and 12 have no transverse tubercle.
What is involved in vesicle targeting and fusion?
V-SNARE on vesicles, T-SNAREs on target membranes. a RABS (GTP binding protein) on the vesicle is localized specific tethering proteins on the membrane - the tether binds RAB, bends, and lets SNAREs bind. They have until the ‘clock’ of RABS hydrolyzing their GTP runs out.
Describe the calcaneal tendon reflex. What if it ruptures?
Normal response plantarflexion - tests S1/S2 roots of tibial nerve. Rupture - cannot rise to tiptoes, bulge in posterior leg, palpable gap where it ruptured.
Where do you find stratified columnar epithelium?
It’s rare - some in the male urethra and in the large ducts of some glands.
Describe CV of the ETC.
Protons leak back into the matrix, causing the F0 rotor to spin. This induces a conformational change in F1. Protons enter through the channel and bind the c subunits of F0. The c subunit then is forced to rotate and causes the gamma subunits to do so as well. THe gamma subunit rotates in the alpha/beta hexamer, causing them to change conformation. There are 3 beta subunits that each have an ATP synthesis site. One full rotation (~10 H+s) drives the synthesis of 3 ATPs.
Where does the fibularis brevis insert?
The tuberosity of the 5th metatarsal.
What are some fat soluble dietary antioxidants?
alpha-tocopherol (vit E), retinoids, carotenoids, ubiquinone.
What modifications does the golgi make?
Glycosylates lipids (this only occurs in the golgi!) O-linked glycosylation of the proteins. Modification of N-linked sugars - galactose, GlcNAc (N-acetylgalactosamine), sialic acid/NANA/N-acetylneuraminic acid (negatively charged)
What are the structures in the posterior mediastinum?
Descending aorta Azygous (and hemiazygous and accessory hemiazygous veins) Thoracic duct Esophagus Sympathetic trunk/splanchnic nerves Intercostal arteries Vagus nerve plexus and trunks (DATES IV)
Where does the trachea divide into the primary bronchi?
At the sternal angle (last bit of cartilage is called the carina).
What is carcinoma?
Cancer originating from epithelial cells.
Describe endoneurium.
Type III collagen, around individual nerve fibers, merges with basal lamina
What is genu varum?
Bowlegged
What is endomysium?
Mainly collagen type I and II. Surrounds individual muscle fibers.
What are some functions of apoptosis in development?
Deleting unwanted structures, sculpting specific tissues by ablating fields of cells, controlling cell numbers, eliminating cells that are nonfunctional/abnormal/dangerous (e.g. self-reactive immune cells)
What does the ER protein modification of a GPI do?
It causes them to clutter in the caveolae (you can also do this if you have an above average TM domain).
What is Lyonization?
At the 2-10,000 cell stage, random X-inactivation, turning a heterozygote female into a mosaic. A good example is X-linked anhydrotic displasia.
Where do you find simple squamous epithelium?
Blood/lymphatic vessels (endothelium), lining of certain body cavities (mesothelium), alveoli in lung, parietal layer of Bowman’s capsule.
What is the G1/S-Cdk complex?
Cdk2-E
What is the lateral collateral ankle ligament made of?
The posterior and anterior talofibular, and the calcaneofibular ligaments.
What detoxifies ingested alcohol?
The SER and peroxisomes equally. This is not usually the case for things!
What is a confidence interval?
It corresponds to 100%-alpha.
Describe the JAK/Stat pathway.
Cytokines bind an RTK that has a JAN kinase that autophorphorylates itself. This recruits Stat2, which is phosphorylated, dimerizes, and goes to the nucleus to affect transcription.
What are colles and smith fractures?
Colles is a fracture where you fall on the palm - radius displaces dorsally. “Dinner fork deformity”. Can come with median and ulnar nerve injury, carpal fracture, radioulnar joinr dislocation. Smith is a reverse Colles fracture - radius displaces ventrally. Can come with acute carpal tunner, ischemia, compressive neuropathy.
What type of glucose transporter is in the basal membrane?
Glucose carriers, passive transport, works with glucose concentration.
Where do you auscultate the superior lobe of the lung?
2nd intercostal space
Where does the semimembranosus insert?
The posterior medial condyle of the tibia.
What is a nerve fiber vs a nerve?
A nerve fiber is an axon or dendrite, a nerve is a collection of fibers (mostly axons and mostly myelinated).
What does the plantar reflex test?
The tibial nerve, roots L4-S2. The normal response is flexion - abnormal is Babinski’s sign.
What is sensitivity (Se, Sn) in a screening test?
Proportion of diseased correctly classified as diseased. High Se means ruling out disease.
Describe the subcostal muscles.
Orientation similar to innermost intercostals, span the intercostal spaces.
Describe H&E stain.
Hematoxylin is basic - stains DNA, RNA, cartilage (basophilic things). Stains them blue. Eosin is acidic - stains cytoplasm, mitochondria, lysosomes, collagen, muscle (acidophilic things). Stains them pink/red/orange.
What do the rough and smooth part of the right atrium derive from embryologically?
Rough - original primitive atrium, Smooth - sinus venarum forms from sinus horn
Describe smooth muscle.
Enclosed by endomysium, full of dense bodies (alpha-actinin, also attach IFs inside the cell and adhesive junctions between cells). THey have caveolae (indentations in sarcolemma) which may act like T-tubules. It can be single-unit/visceral (gap junctions, spontaneous APs) or multi-unit (has motor units, graded contractions, cells structurally independent). Instead of a neuromuscular junction, there are axonal varicosities.
What is cardiolipin?
Mitochondria imports lipids from SER and makes them into cardiolipin - a “double phospholipid” with 4 FA tails. It is about 20% of the lipid in the mitochondrial IM and packs tight to help resist the PMF stress.
What are the anastomoses of the heart?
Right marginal branch and left marginal branchat IV branches. Posterior interventricular artery and LAD. Circumflex artery with RCA at coronary sulcus.
Where do you find the posterior tibial artery pulse?
Inferior to the medial malleolus in the tarsal tunnel.
What’s the name of the deep fascia of the foot?
The pedal fascia.
What do the sympathetic fiber axons from L1-L2 do?
Form the lumbar splanchnic nerve -> innervate the inferior mesenteric ganglia.
