Physiology Flashcards
Which of the ff. Steps w/n the beta cell will bring about insulin secretion?
A. Opening of the K channels by sulfonylureas
B. Closing of calcium channels to prevent influx of calcium
C. Repolarization of the beta cell
D. Increase in intracellular calcium
E. None of the above
D
*depolarization opens calcium channels which will lead to an INCREASE IN INTRACElLULAR CALCIUM and then to secretion of insulin
This type of intracellular structures between cell membranes is responsible for tight intercellular adhesions:
Macula adherens
In the cardiac action potential, phase 2 is characterized by:
Calcium influx
- Phase 0 - influx of Na
- Phase 1 - transient efflux of K
- Phase 2 - influx of Ca and Na
- Phase 3 - efflux of K> influx of Ca and Na
- Phase 4 - Na-K pump
*Ivabradin (Corlnor)- slows down the HR by targeting the Na (If) Channels
This tactile receptor receives steady-state signal for continuous touch and determines texture:
Merkel disc
These cells are output cells of the retina in which axons form the optic nerve
Ganglion cells
What cells maintains the internal geometry of the retina
Mueller cells
*Bipolar cells, Amacrine and horizontal cells- interneurons
Blood flow per grams of tissue is greatest in which organ
Kidney
*20% of cardiac output
In the atrial pressure curve, this is represented by venous blood going to the atria:
A. A wave B. C wave C. V wave D. X descent E. Y descent
C
- A wave- atrial contraction
- C wave- contraction of the ventricle (bulging of the tricuspid valve)
- V wave- venous blood going to atria; back-pressure wave from blood filling the right atrium
- X descent- drop in atrial pressure during ventricular systole caused by atrial relaxation
- Y descent- caused by early ventricular filling
Tricuspid regurgitation- giant (V) waves, CV wave
Atrial fibrillation
Absent a wave
Heart block, prominent A waves
Cannon waves
Cushing reflex triad
Hypertension
Bradycardia
Irregular respirations/ bradypnea
Oxygen-hemoglobin dissociation curve. Shift to the right:
Increased P50 Acidosis/ dec PH Increase temp Increase PCO2 Increase 2,3-BPG bisphosphoglycerate increase altitude
Right=Release
O2 released easily
Respiratory responses to high altitude
Dec. alveolar PO2 Dec. Arterial PO2 Inc. pulmonary vascular resistance - because of hypoxic vasoconstriction Inc. arterial pH Inc. respiratory rate
Part of the nephron most susceptible to hypoxia and toxins and is considered as the WORKHORSE of the nephron
Proximal convoluted tubule
*reabsorption usually happens here
Vomiting center in the medulla oblongata is called
Area postrema