Chapter 10: Homeostasis Flashcards
List the structures in the excretory pathway, from where filtrate enters the nephron to the excretion of urine from the body.
- Bowman’s space
- proximal convoluted tubule
- descending limb of the loop of Henle
- ascending limb of the loop of Henle
- distal convulted tubule
- collecting duct
- renal pelvis
- ureter
- bladder
List the vessels in the renal vascular pathway, starting from the renal artery and ending at the renal vein.
- Renal artery
- Afferent arteriole
- glomrelus
- efferent arteriole
- vasa recta
- renal vein
What arm of the parasympathetic nervous system is responsible for contraction of the detrusor muscle.
The parasympathetic nervous system causes ontraction of the detrusor muscle.
What are the three processes by which solutes are exchanged between the filtrate and the blood? What happens in each process.
- Filtration is the moevement of solutes from blood into filtrate at Bowmans’s capsule.
- Secretion is the movement of solutes from blood into filtrate anywhere besides Bowman’s capsule.
- Reabsorption is the movement of solutes from filtrate into blood.
For each segment of the nephron listed below, what are its majorfunctions.
- Bowman’s capsule:
- Proximal convoluted tubule:
- Descending limb of the loop of Henle:
- Ascending limb of the loop of Henle:
- Distal convoluted tubule:
- Collecting Duct:
- Bowman’s capsule: The site of filtration, through which water, ions, amino acids, and vitmains, and glucose pass (essentially everything besides cells an proteins).
- Proximal convoluted tubule: Controls solute identity, reabsorbing vitamins, amino acids, and glucose, while secreting potassium and hyrogen ions, ammonia, and urea.
- Descending limb of the loop of Henle: important for water reabsorption, and uses the medullary concentration gradient.
- Ascending limb of the loop of Henle: important for salt reabsorption and dilution of the urine in the diluting segment.
- Distal convoluted tubule: like the PCT, is important for solute identity by reabsorbing salts while secreting potassium and hydrigen ions, ammonia, and urea.
- Collecting Duct: is important for urine concentration; its variable permeability allows water to be reabsorbed based on the needs of the body. Responsive to both Aldosterone and Antidiuretic Hormone (Vasopressin or ADH)
____ consists of smooth muscle , is contracted in its normal state. It is under involuntary control.
____ consists of skeletal muscle and is under voluntary control.
Internal Urethral Sphincter
External Urethral Sphincter
When the bladder is full, stretch receptors convey to nervous system that the bladder requires emptying. This causes the Parasympathetic neurons to fire, and the detrusor muscle contracts. This contraction also causes the internal sphincter to relax. This refles is known as the____.
Micturtition Reflex
The glomerulus is like a strainer. Small molecules will _____. Large molecules will _____.
- Small molecules will pass through the tiny pores (such a glucose, which is later reabsorbed)
- Large molecules will notpass through which as proteins and blood cells. If blood cells or proteins are found in the urine. This indicated a health problem at the glomeruls level.
Two main goals of the kidneys
- Keep what the body needs and lose what it doesnt needs.
- Concentrate the urine to conserve water.
- The horizontal structres are primarily focused on identity of the particles (Keep what the body needs and lose what it doesn’t)
- The segments that are vertical in the diagram are primarily focused on the volume and concentration of the urine (Concentrate the urine to conserve water).**
- Name the structures of each
- Bowman’s Capsule, Proximal Conculted tubule, and Distal Convuluted tubule.
- Loop of Henle and The Collecting Duct
MNEMONIC
Major waste products excreted in the urine: Dump the HUNK
- H+
- Urea
- NH3
- K+
Together, the vasa recta and nephron create a ____.
Countercurrent Multiplier System
This means that the flow of filtrate through the loop of Henle is in the opposite direction from the flow of blood through the vasa recta.
If the vasa recta and the nephron flowed in the same direction, what would happen?
They would quickly reach equilibrium and the kidney would be unable to reabsorb as much water.
By making the vasa recta flow in opposite directions, _____.
The filtrate is constatly being exposed to hypertonic blood cells, which allows maximum reabsorption of water.
What is special about the Ascending Limb Loop of Henle?
It is the only portion of the nephron that can produce urine that is more dilute then the blood. This is important in periods of over hydration and provides a mechanism for elimnating excess water.
Bicarbonate Buffer System Equation
- What happens to respitory systemnd Kidneys?
- If pH is too High
- If pH is too Low
- If pH is too High
- Prolonged vomitiing causes excessive loss of H+. The gastric mucosa produces and excess of HCO-3 to replace H+ lost by vomiting. Hypoventilation
- The kidneys can excrete more bicarbonate and increase the reabsorption of hydrgen ions.
- If pH is too Low
- increasing the respiratory rate blows off more CO2 and favors the conversion of H+ and HCO-3 to water and carbon dioxide, increasing the blood pH.
- The kidneys will excrete more hydrogen ion ad increase reabsorption of bicarbonate, resulting in a higher pH.
