HIGH YIELD POINT FOR PHYSIOLOGY 2015
http://www.doctorsquiz.com important topics for DNB-CET, AIPGMEE, FMGE,
DNB-PDCET, UPSC-CMS online medical examination .
Respiration changes with increasing altitude: • respiratory alkalosis. hypoxcmia due to decreased atmospheric pressure not a decrease in% oxygen in air.• increase in 2.3 BPG right shifts theODC
Effect of Vl P (vasointestinal peptide) and enkephalins on GI tract: • VlP- relaxes smooth
muscle, increases intestinal secretion. increases pancreatic secretion. • enkephaiins (opiatesj•
contract smooth muscle. decrease intestinal secretion
Know PC01 dissociation curve
lnbibin: • synthesized in Sertoli cells in seminiferous tubules. • negative feedback with FSH. • increased if seminiferous tubules are destroyed, • normal if Leydig cells an: destroyed. since testosterone has a negative feedback with LR
Calculations: • alveolar ventilation- PA02 = Pi02 - PACO~/R. where PiO: equals % oxygen x 713) and R is the respiratory quotient that normally equals 0.8, subtract PaO~ from
PAO~ and you have the A-a gradient. • Fick's equation for cardiac output- cardiac output ml.rmin e- oxygen consumption -;. oxygen in pulmonary vein - oxygen in pulmonary artery
Hormone increasing/decreasing gastric secretion: • gastrin, • hormones inhibiting acid secrcrion- secretin and gastric inhibitory peptide
Placental anatomy/physiology: • maternal surface has slightly bulging areas called cotyledons. which are covered by a layer of decidua basalis, • fetal surface is entirely covered by the choriomc plate- chorionic vessels converge with the umbilical cord, which is composed of 2 umbilical arteries (venous blood returning from the fetal heart) and I umbilical vein (carries oxygenated blood from the placenta), • chorionic villus/umbilical cord- choriomc villi project 1 the intervillous space. which contains maternal blood from which oxygen is extracted: spiral arteries from the uterus empty into the space, chorionic villi are lined by trophoblastic tissue: outside layer is composed of syncytiotrophoblast: synthesizes hCG and human placental lactogen (growth hormone of pregnancy) and inside layer is composed of cytorrophoblast: clear cells. the interior of the chorionic villus has fetal blood vessels, which coalesce to form the chorionic vessels that converge with the umbiiical cord. • the umbilical cord contains 2 umbilical arteries (contains deoxygenated blood exiting the feral heart and returning to the placenta) and 1 umbilical vein (contains oxygenated blood)
Effect of increased total peripheral resistance on vascular function curve: • same as the venous return curve. which depicts the relationship between venous return and right atrial pressure. • increasing: TPR (vasoconsrriction) decreases venous return to heart. decrease right atrial pressure. and decrease cardiac output- this causes a counterclockwise rotation of the vascular function curve. • decreasing
TPR (vasodilation) causes a clockwise rotation of the curve- venous return increases. right atrial pressure increases, and cardiac output increases
hCG: • has luteinizing hormone activity, • keeps corpus luteum of pregnancy synthesizing progesterone until 8-10 wks and then placenta takes over that function
Stimulation of histamine H2 receptors: increases secretion of acid by parietal cells
GI peptide injected into cerebrospinal fluid that increases appetite for carbohydrate: sornatostatin- this normally is made in hypothalamus where it functions to inhibit growth hormone. hence inhibiting GH causes hypoglycemia and the body would crave more carbohydrate to increase glucose levels
