Biophysics

259) The underwater rock is 6 km from a submarine. What is the time (starting from sound emission) of echo return to the sonar if the speed of sound in water is 1500 m/s?

261) The mean kinetic energy of particles in an ideal gas is:

264) Viscous resistance (haemodynamic resistance) is defined as:

172) Electrical capacitance of a membrane:

283)  After a light absorption by a photoreceptor the membrane potential:

284)  The force of electrostatic interaction between two electrical charges is:

287) After the light absorption by a photoreceptor the membrane potential is:

341. Which type of neurons are typically unipolar?

342. Which neurotransmitter is released by the mammalian rod cells in the retina:

343. Indicate the fastest mechanism of communication between two cells

344. Choose the best characterization of myasthenia gravis

345. indicate the major inhibitory neurotransmitter in the adult brain

346. According to Van’t Hoff’s law:

347. how the osmotic pressure (according to the Vant Hoff’s law) depends on the solute concentration c:

348. When cells are suspended in a hypotonic solution:

349. When in the isolated system entropy increases:

350. When the degree of order in the isolated system increases

351. The internal energy of a thermodynamic system consists of

352. According to the first law of thermodynamics

353. According to the first law of thermodynamics the change of the internal energy (deltaU) of any thermodynamic system is

354. According to the first law of thermodynamics the change of the internal energy (delta-U) of any thermodynamic system is:

355. When in the isolated system entropy increases:

356. In the equilibrium state:

357. What will be the concequences of an increase in the excitable cell’s input resistance?

358. According to the fluid mosaic model biological membranes are:

359. Ultrasound frequency increased by 100% indicates how much changed the acoustic impedance within a homogenous medium

360. In the harmonic movement a particle is oscillating around the equilibrium point and A denotes the amplitude i.e. the maximum absolute distance of particle from the equilibrium point. Indicate the situation in which the absolute value of the harmonic force (F) is reaching its maximum: (y – distance from equilibrium point, -A ≤ y ≤ A).

361. Intensity of electrical field E

362. Indicate the necessary condition for creation of positon-negaton pair

363. The energy of a hydrogen bond

364. The energy of a hydrogen bond is:

365. The phenomenon of viscocity in liquids can be described as fallows:

366. What happens to the optical power of a lens if its curvature radii gets 50% shorter?

367. The optical power of the eye system is approximately:

368. The ultrasonograph emits a pulse of ultrasound wave into the examined soft tissue at time t=0. The echo is detected at 0,1 ms. Assuming the sound velocity in the soft tissue 1500m/s indicate the distance between the ultrasonograph’s head and the tissue from which the sound was reflected.

369. If the medium density increases two times but the speed of acoustic wave propagation does not change then the acoustic impedance is:

370. The current density for a considered ion is:

371. In the electrolyte, local intensity of electric field

372. In an electrophysiological experiment the number of moles of electrical charges per membrane surface unit and per unit time is determined. The name of the physical quantity measured in this experiment is:

373. The ultrasonograph emits a pulse of ultrasound wave into the examined soft tissue at time t=0. The echo is detected at 0,1 ms. Assuming the sound velocity in the soft tissue 1500m/s indicate the distance between the ultrasonograph’s head and the tissue from which the sound was reflected.