Description : The action potential of a neuron a. is initiated by efflux of Na+ b. is terminated by efflux of K+ c. declines in amplitude as it moves along the axon d. results in a transient reversal of the ... the cell membrane e. is not associated with any net movement of Na+ or K+ across the cell membrane
Last Answer : is terminated by efflux of K+
Description : A semi permeable membrane is stretched across a chamber filled with water. The membrane is only permeable to water. 60 mg of salt is added to the left side of the chamber. Which of the following will ... right side (C) Water will move toward the left side (D) salt will move toward the left side
Last Answer : (C) Water will move toward the left side
Description : Osmosis is a. movement of solvent across a semipermeable membrane from an area where the hydrostatic pressure is high to an area where the hydrostatic pressure is low b. movement of solute across a ... area in which it is in high concentration to an area in which it is in low concentration
Last Answer : movement of solvent across a semipermeable membrane from an area in which it is in high concentration to an area in which it is in low concentration
Description : $ Positive diffusion occurs against the concentration gradients. ! Osmosis does not require a semi-permeable membrane.
Last Answer : $ Positive diffusion occurs against the concentration gradients. ! Osmosis does not require a semi-permeable ... D. If both As and R are wrong.
Description : What is the meaning of selectivity permeable?
Last Answer : Selective permeability refers to the function of plasmamembranes that is needed to maintain homeostasis in a cell andprevent foriegn substances from entering through the cellswalls.Some molecules can pass, some are blocked
Description : A striking feature of living cells is a marked difference between the composition of the cytosol and the extracellular milieu. Which of the following statement(s) concerning the mechanisms of maintenance ... d. The selectivity of cell membranes relates only to ions and not organic compounds
Last Answer : Answer: a The survival of the cell requires that cytosolic composition be maintained within narrow limits, despite the constant influx of nutrients and the simultaneous outflow of waste. A ... be altered drastically as a result of regulatory or signaling processes that occur within the cell
Description : A tube of uniform cross sectional sectional area `1 cm^(2)` is closed at one end with semi permeable membrane. A solution having 6g glucose per 100 ml
Last Answer : A tube of uniform cross sectional sectional area `1 cm^(2)` is closed at one end with semi permeable membrane. A ... k^(-1)`, density of Hg=13.8 g/cc)
Description : The process of diffusion of one liquid into the other through a semi permeable membrane is called (A) Viscosity (B) Osmosis (C) Surface tension (D) Cohesion
Last Answer : Answer: Option B
Description : Which of the following statement(s) is/are true concerning water movement across cell membranes? a. Water moves only actively through cell membrane transport proteins b. For most cells of ... cells such as the glomerulus of the kidney actively transport water to maintain hydrostatic pressure
Last Answer : Answer: b, c The energetics of water transport across cell membranes is simplified by the fact that water moves only passively due to gradients of hydrostatic pressure or water ... water is distributed at equilibrium. Water distribution is determined entirely by solute to solute distribution
Description : What process moves materials through a cell from areas low concentration to areas of high concentration?
Last Answer : active transport
Description : Which of the following criteria does not pertain to facilitated transport? (a) Transport saturation (b) Uphill transport (c) Requirement of special membrane proteins (d) High selectivity
Last Answer : (b) Uphill transport
Description : A key process in metabolism is the transport of hydrogen ions (H+) across a membrane to create a concentration gradient. Explain which arrangement of hydrogen ions (unequal concentration or equal concentration) allows work to be done.
Last Answer : It is clear that an unequal concentration, not an equal one, would be the only possibility that work will be done; the unequal concentration of hydrogen ions would allow them to flow across the membrane and increase not only entropy but also work.
Description : Substances insoluble in a membrane are carried across the membrane with the concentration gradient by means of a carrier molecule in a process known as: a) osmosis. b) diffusion. c) active transport. d) facilitated diffusion.
Last Answer : ANSWER: D -- FACILITATED DIFFUSION.
Description : What is a semi-permeable membrane? -Biology
Last Answer : answer:
Description : Why is the cell membrane considered a semi-permeable membrane? -Biology
Description : what is a selectively permeable membrane -Biology
Description : What is the selectively permeable membrane of the cell? -Do You Know?
Description : $ The cell membrane helps in pinocytosis and phagocytosis. ! Cell membrane is permeable.
Last Answer : $ The cell membrane helps in pinocytosis and phagocytosis. ! Cell membrane is permeable. A. If both As and ... wrong D. If both As and R are wrong.
Description : What do the terms selective permeability and semi permeable to have to do with the cell membrane?
Last Answer : Need answer
Description : Mitochondrial membrane is permeable to (A) Short chain fatty acids (B) Medium chain fatty acids (C) Long chain fatty acids (D) All of these
Last Answer : Answer : A
Description : In all cells the cytoplasm is externally bounded by a semi - permeable membrane. It is known 4s ..........0+5
Last Answer : Cell membrane/Plasma membrane
Description : What is selectively permeable membrane?
Last Answer : A membrane which controls the movement of materials passing through it is called a selectively permeable membrane. It allows some but not all substances to pass through it.
Description : Plasma membrane in resting condition is very permeable to a. K b. Cl c. Both d. None of them
Last Answer : Cl
Description : When a neuron is in resting state i.e., not conducting any impulse, the axonal membrane is (a) comparatively more permeable to Na+ ions and nearly impermeable to K+ ions (b) equally permeable to both ... + and K+ ions (d) comparatively more permeable to K+ ions and nearly impermeable to Na+ ions.
Last Answer : (d) comparatively more permeable to K+ ions and nearly impermeable to Na+ ions.
Description : Which of the following statements regarding mitochondrial membrane is not correct ? (a) The outer membrane resembles a sieve. (b) The outer membrane is permeable to all kinds of molecules. (c) ... in the outer membrane. (d) The inner membrane is highly convoluted forming a series of infoldings.
Last Answer : (c) The enzymes of the electron transfer chain are embedded in the outer membrane.
Description : Which of the following statements regarding mitochondria is incorrect? (a) Mitochondrial matrix contains single circular DNA molecule and ribosomes. (b) Outer membrane is permeable to monomers of ... transport are embedded in outer membrane. (d) Inner membrane is convoluted with infoldings.
Last Answer : (c) Enzymes of electron transport are embedded in outer membrane.
Description : This antihelminthic agent makes the membrane permeable to calcium ions. a. Mebendazole b. Pentamidine c. Ivermectin. d. Praziquantel
Last Answer : d. Praziquantel
Description : What is the selectively permeable membrane of the cell?
Last Answer : Plasma lemma
Description : 11. Which of the following theories explain that plasma membrane is selectively permeable: (a) Unit membrane theory (b) Cascade theory © Sandwich theory (d) Fluid Mosaic theory
Last Answer : Answer: d Fluid Mosaic theory
Description : There are two properties of the cell necessary to maintain nonequilibrium cellular composition; the first is selectivity and the second is energy conversion. Which of the following statement(s ... transported via secondary active transport include hydrogen ions, calcium, amino acids and glucose
Last Answer : Answer: c, d The selectivity of the plasma membrane, although impressive, cannot account for the nonequilibrium composition of living cells. A cell can be maintained in a nonequilibrium state only by ... to drive the transport of a second species such as protons, calcium, amino acids, or glucose
Description : The β adrenergic blocker having β1 selectivity, intrinsic sympathomimetic activity and membrane stabilizing property is: A. Carvedilol B. Atenolol C. Acebutolol D. Metoprolol
Last Answer : C. Acebutolol
Description : The β adrenergic blocker having β 1 selectivity, intrinsic sympathomimetic activity and membrane stabilizing property is: A. Carvedilol B. Atenolol C. Acebutolol D. Metoprolol
Description : _________ is defined as the geometric mean of the relative rejections and the relative recoveries of two minerals. (A) Separation efficiency (B) Selectivity index (C) Concentration ratio (D) None of these
Last Answer : (B) Selectivity index
Description : Active and passive transports across cell membrane differ in (a) passive transport is nonselective (b) passive transport is along the concentration gradient while active transport is due to metabolic ... (d) passive transport is confined to anions while active transport is confined to cations.
Last Answer : (b) passive transport is along the concentration gradient while active transport is due to metabolic energy
Description : What causes image interference? A. Low gain B. High IF C. Poor front-end selectivity D. Low signal-to-noise ratio
Last Answer : C. Poor front-end selectivity
Description : ______________________ has the advantage of being high in selectivity, low cost, immediacy, and interactive capabilities. 1. Direct mail 2. Outdoor 3. Online 4. Radio 5. None of these
Last Answer : Online
Description : What area around it so has a high concentration of sodium ions are the result the cell membrane expands and burst which problem was the cell most likely having?
Last Answer : What is the answer ?
Description : Catalyst carriers (A) Have very high selectivity (B) Increase the activity of a catalyst (C) Provide large surface area with a small amount of active material (D) Inhibit catalyst poisoning
Last Answer : (C) Provide large surface area with a small amount of active material
Description : A high surface area to volume ratio in cells is important because it (a) Enables efficient transfer of wastes, nutrients and gases across the cell membrane (b) Prevents overproduction of cell ... self and non-self (d) Provides for better structural support to cope with external physical pressure
Last Answer : Ans:(a)
Description : Synthetic rubber (A) Deforms, if stretched to double of its original dimension (B) Is brittle at low temperature (C) Is softer at higher temperature (D) Is highly permeable to air & water and is readily attacked by chemicals & atmospheric gases
Last Answer : (D) Is highly permeable to air & water and is readily attacked by chemicals & atmospheric gases
Description : Methicillin resistant staphylococci do not respond to ß-lactam antibiotics because (a) They produce a ß-lactamase which destroys methicillin and related drugs (b) They elaborate an amidase which destroys ... low affinity for ß-lactam antibiotics (d) They are less permeable to ß-lactam antibiotics
Last Answer : Ans: C
Description : Methicillin resistant staphylococci do not respond to β-lactam antibiotics because: A. They produce a β-lactamase which destroys methicillin and related drugs B. They elaborate an amidase which destroys ... low affinity for β-lactam antibiotics D. They are less permeable to β-lactam antibiotics
Last Answer : C. They have acquired penicillin binding protein which has low affinity for β-lactam antibioti
Description : In liquid extraction, if the selectivity is unity, then (A) Separation of the constituents is the most effective (B) No separation will occur (C) Amount of solvent required will be minimum (D) Solvent flow rate should be very low
Last Answer : (B) No separation will occur
Description : In passive transport materials move from an area of higher concentration to an area of lower concentration through a cell membrane.?
Last Answer : yes
Description : Which ion moves freely through the plasma membrane a. Na b. Cl c. k d. HCo3
Description : The process by which cell can take in fluid and molecules too large to be carried across the plasma membrane by active transport is called a. phagocytosis b. Pinocytosis c. absorption d. diffusion
Last Answer : Pinocytosis
Description : If the concentration of the dye was decreased would the distance it moves increase?
Last Answer : decrease it the right answer
Description : Pick out the wrong statement. (A) Critical moisture content is not a property of the material itself (B) A sharp increase in pressure drop gives an indication of the flooding in a ... unity (D) Dehydration of ethyl alcohol is most economically done by molecular distillation at very high vacuum
Last Answer : (D) Dehydration of ethyl alcohol is most economically done by molecular distillation at very high vacuum
Description : In autocatalytic reactions, (A) One of the reactants acts as a catalyst (B) One of the products acts as a catalyst (C) Catalysts have very high selectivity (D) No catalyst is used
Last Answer : (B) One of the products acts as a catalyst