419 Final - PollEverywhere Exam Questions & Answers

419 Final - PollEverywhere Exam Questions & Answers-(Lecture 1) Which cells in the body do not contain the entire genome? A. Lymphocytes B. Erythrocytes C. Beta Cells D. Neurons E. None of the above - B. Erythrocytes (Lecture 1) The secretion of hormones by the pituitary gland is an example of: A. Autocrine signaling B. Paracrine signaling C. Endocrine signaling D. Direct signaling across gap junction E. None of the above - C. Endocrine Signaling (Lecture 1) Two balloons are charged with an identical quantity and type of charge: -6.25 nC. They are held apart at a separation distance of 61.7 cm. Determine the magnitude of the electrical force of repulsion between them. A. 9.23x10-7 B. 10.34x10-6 C. 5.34x10-7 D. 15.89x10-7 E. None of the above - A. 9.23x10-7 (Lecture 2) Blood flows through an artery with a diameter of 5 mm at a velocity of 9 cms/. If the diameter of the artery then decreases to 3mm, what is the new velocity? - 25cm/s (Lecture 2) One liter of water of water contains 55.5 moles of water. Accordingly, the concentration of water in 1 liter of water is 55.5M. Water dissociation produces 10-7 M [H+] and 10^-7 M of [OH-]. Calculate Keq - 1.80x10-16 (Lecture 2) Voltage across a barrier is 80mV, and the barrier is permselective to K+. What is the K concentration ratio across the barrier? - Kin/Kout = 20.08 (Lecture 2) Solution A and Solution B are separated by a membrane whose permeability to urea is 2x10-5 cm/sec and whose surface area is 1 cm2. The concentration of urea in A is 10 mg/mL, and the concentration of urea in B is 1 mg/mL. The partition coefficient for urea is 10-3, as measured in an oil-water mixture. What are the initial rate and direction of net diffusion of urea? - Jx = 18x10-5 cm*m/s from A --> B (Lecture 2) The Na+ permeability of a lipid bilayer is 1x10-12 cm/s. If the [Na+] in plasma is 150 mM and in the cell is 15 mM. What is the rate of Na+ leakage into the cell? - Jx = 1.35x10-13 cm*m/s (Lecture 3) There are a variety of transporters for glucose that are called GLUT (for glucose transporter). The GLUT-1 transporter imports glucose into a variety of cell types. This is an integral membrane protein with a molecular weight of 45 kDa. Its Km for glucose is 1.5 mM. Glucose is typically about 100 mg% in the extracellular fluid. At what fraction of Qmax will glucose be transported at this concentration? - 0.78Qmax (Lecture 3) Where does the energy come from for movement of materials by passive transport? - Concentration gradient (Lecture 3) Where does the energy come from for movement of materials by primary active transport? - ATP (Lecture 3) Energy for secondary transport comes from concentration gradients. (T/F) - False, comes from the electrochemical gradient (Lecture 3) What method provides the fastest transport? A. Membrane channels B. Pumps C. Carriers - A. Membrane channels (Lecture 4) The concentration of nonpenetrating solutes in a solution, not the total osmolarity determines its tonicity - iso-, hypo- or hypertonic. (T/F) - True (Lecture 4) Solutes that readily diffuse through lipid bilayers (penetrating solutes) do not contribute to the tonicity of a solution. (T/F) - True (Lecture 4) What happens to an RBC placed in a hypoosmotic solution? A. Shrinks B. Swells C. Doesn't change D. Not enough information. - D. Not enough information (Lecture 4) The osmolarity of a solution of 50 mmol/L MgCl2 is closest to the osmolarity of which of the following: A. 50 mmol/L NaCl B. 100 mmol/L urea C. 150 mmol/L NaCl D. 150mmol/L urea - D. 150mmol/L urea (Lecture 4) Blood volume must be restored in a person who has lost large amounts of blood due to serious injury. This is often accomplished by infusing isotonic NaCl solution into the blood. Why is this more effective than infusing an iso-osmotic solution of a penetrating solute, such as urea? - Urea equilibrates so you won't get the same effect you need to get