BIOS 1710 SI Week 6 Session 1

Tuesday 7:05-8:05 Morton 326

Thursday 7:05-8:05 Morton 218

  1. Please describe the steps in excretion.
  1. Give a brief description of the excretory organs of flatworms, earth worms, and insects.
  1. What is the excretory organ in vertebrates? What is the functional unit of this organ?
  1. Describe how fluid moves through the vertebrate excretory system.
  1. Outside of the kidney:______::Inside of the kidney:______
  1. Where are the majority of nephrons located?
  1. Describe the following parts of the nephron
  2. Renal corpuscle:
  3. Proximal convoluted tubule:
  4. Loop of Henle:
  5. Distal convoluted tubule:
  6. Collecting duct:
  1. What are the four parts of the loop of Henle?
  1. What is the glomerulus? Why are its capillaries unique?
  1. ____% of the water that leaves as filtrate is reabsorbed each day.

_____% is absorbed in the proximal tubule.

  1. Why are microvilli important to the excretory system?
  1. If water isn’t reabsorbed by active or passive transport, how is it reabsorbed?
  1. It is well known that caffeine increases urine output, which of the following mechanisms could result in increased urine production?
  2. Increase in blood pressure
  3. Increased Na reabsorption from the proximal tubule
  4. Decreased Na reabsorption from the proximal tubule
  5. Both A and B
  6. Both A and C
  1. How is it possible that filtrate has the same osmolarity as blood plasma, but human urine is 4x more concentrated than blood plasma?
  1. How is the gradient in the loop of Henle created?
  1. Why are the vasa recta important in the role of maintaining the osmotic gradient of the loop of Henle?
  1. Which of the following statements about kidney function is NOT correct?
  2. The thin ascending limb of the loop of Henle is high permeable to salt
  3. Reabsorption of water and solutes takes place primarily in the proximal tubule
  4. The loop of Henle acts to maintain the osmotic gradients via a countercurrent exchanger with no energy required
  5. The descending limb of the loop of Henle is high permeable to water
  1. Fluid in the distal tubule is ______relative to the blood.
  1. Describe the osmolarities of fluid entering the distal tubule as opposed to urine.
  1. How is the amount of Na and Cl absorbed in the distal tubule controlled?
  1. Circle one and fill in the blank: Urine traveling down the collecting duct loses/gains water because of the ______.
  1. Describe how the permeability of the collecting duct is controlled by ADH.
  1. Describe how the kidneys help increase blood pressure when it is low.
  1. What do hormones respond to?
  1. Give five examples of hormones and their functions or what they respond to.
  1. Describe the process in hormonal regulation of metamorphosis of insects.
  1. If after the third instar JH is much reduced, what is likely to happen?
  2. The insect with shrink and die
  3. The insect will molt as usual but will not go through metamorphosis
  4. The insect will undergo premature metamorphosis
  5. Nothing, thyroid hormone controls metamorphosis in insects
  1. Give at least two examples of hormones underlying homeostasis in humans.
  1. Describe the process of glucose homeostasis/negative feedback (both when glucose is low and high).
  1. If someone’s glucose levels have fallen:
  2. They probably have diabetes
  3. Their pancreas will release glucagon
  4. Their pancreas will release insulin
  5. Both A and B
  6. Both A and C
  1. Describe an example of positive feedback in humans.
  1. What are the three types of hormones? How are they similar?
  1. Where do peptide and amine hormones bind? Why?