Biophysics

374. Figure presents a dipole. The value of the electrical potential at the distance R on the solid line is V(R). What would be the value of the potential when increasing the distance three times (3R) on the same direction defined by the solid line in the figure?

375.The intensity of electrical field is defined as:

376. The current density (j) is defined as

377. Indicate in which units is measured the ECG signal:

378. Induction of magnetic field changed from 1 Tesla to 2 Tesla. Induce how the resonance frequency in the NMR phenomenon was affected

379. The conditions of the nuclear magnetic resonance for protons are met when

380. The number of orientations that magnetic moment of proton c…. External magnetic field is:

381. The magnitude of the chemical shift is:

382. Where are localized the acethylcholine receptors at the neuromuscular junction?

383. Synaptic transmission at the rod’s synapse occurs at its maximum rate

384. Choose the best characterization of myasthenia gravis

385. The intracellular concentration of chloride ions is increased while the extracellular one remains unchanged. Indicate how this change will affect the value of the equilibrium potential for chloride ions (VCl).

386. What happens to the membrane capacitance if its surface and thickness increase two fold (two times) ?

387. Indicate the name of the disorder characterized by the following symptoms: muscle fatigability, deficit of acetylcholine receptors at the muscular endplates :

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

389. For a thick lens (as in the eye) the distance between the image and the lens is measured as:

390. Enhancement of so called f-type current in the sinoatrial node will result in:

391. The total energy of a molecule is equal to:

392. Indicate a typical width of the synaptic cleft (distance between pre- and postsynaptic membrane) of a chemical synapse:

393. The chemiosmotic gradient that couples the oxidation/reduction processes occuring during the oxidative phosphorylation and the production of ATP is provided by

394. The chemiosmotic proton gradient that couples the oxidation/reduction processes occuring during the oxidative phosphorylation and the production of ATP created by:

395. Proper description of fluorescence and phosphorescence occurring after absorption of photon is given by:

396. During the processes of absorption and fluorescence the energy of the molecule is:

397. Find a true sentence describing fluorescence:

398. The phenomenon of diffusion is quantitatively described by:

399. The sound velocity in air and water are

400. Human ear shows the highest sensitivity for sounds characterized by:

401. Blood velocity in the vessels can be estimated when applying:

402. Indicate proper statement regarding X and gamma rays

403. The feature that a lens focuses the light not at a focal point but at a blurred spot is referred to as:

404. Typically, the wavelength of absorbed photon is:

405. The energy of interaction between the magnetic moment and the external magnetic field is minimal when:

406. In the MRI scanning, the gradients of magnetic field are used to:

407. Indicate where in the heart tissue, the propagation of excitability occurs with the lowest velocity

408. Sensory neurons are typically:

409. Indicate a typical width of the synaptic cleft (distance between pre- and postsynaptic membrane) of a chemical synapse:

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

411. Indicate the fastest mechanism of communication between two cells

412. Nicotinic Acetylcholine receptors are:

413. In myothonia congenita the skeletal muscle fibers are: