Ch. 8 Components of the Urinary System Flashcards
COMPONENTS OF THE URINARY SYSTEM
.Where is urine made?
Where is urine stored?
What are the components of the urinary system?
2 Kidneys
2 Uterers
1 Urinary Bladder
1 Urethra
What’s the Kidney’s function?
- The Kidneys are responsible for making a fluid called urine. Once urine is made, the urine is released and then it goes to the ureters.
What is the Ureter?
What are the Ureters function?
- Small cuplike regions known as minor calyces that give rise to the renal pelvis.
- It propel the urine via peristalsis to the bladder.
What is the Urinary Bladder’s function?
- The Urinary Bladder stores urine until it’s time to be released.
- When it’s the appropriate time to release urine, the bladder contracts and expels the urine via the urethra on out of the body.
Define Micturition
- The process by which urine is released from the body.
What does urine consist of?
- Urine consists of waste products as well as substances that are in excess of the body’s needs.
CHARACTERISTICS AND COMPONENTS OF NORMAL URINE
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When does the body produce normal urine?
- When the body has a normal amount of hydration.
When is urine different than normal?
- When the body is dehydrated or overhydrated
What is the Volume of normal urine?
What color is it ?
What is its pH?
- 1.5 Liters per day
- Light Yellow (due to the pigment Urobilin)
- Typically Acidic (usually around pH 6)
Where does Urobilin come from?
- It comes from the conversion of the bile pigment bilirubin in the large intestine.
What color is Urine when the body is OverHydrated?
What color is Urine when you’re Dehydrated?
- Clear (due to a lot more water)
- Dark Yellow
Why is Urine typically Acidic?
- Urine is typically acidic because a main way of getting rid of acids from the body is by excreting some of the Hydrogen Ions into Urine
- ex: If you drink a lot of Orange Juice over a short period of time, some of the Hydrogen Ions from the citric acid in the orange juice will leave the body via urine.
What are the 3 Main components of Urine? Give examples for each.
- Nitrogenous wastes - Urea, Ammonia, Creatinine, Uric
Acid, Urobilin - Excess substances - Water, Electrolytes (ions)
- Other substances - Hormones, Ketones, and any
Drugs a person has taken
What is Urea?
Where is Urea derived from?
hint: derived same way as ammonia
Which Organ makes Urea?
Explain.
- Urea (the most common waste product in urine)
- Just like Ammonia, the catabolism (breakdown) of amino acids in hepatocytes, which are liver cells.
- The Liver makes urea!!!
- Explanation: from the liver, urea enters the bloodstream and the kidneys take up urea from the blood and put the urea into urine for excretion from the body.
What is the main COMPONENT of urine?
- WATER.
Where is Creatinine derived from?
Where is Uric Acid derived from?
- Creatinine comes from the breakdown of creatine phosphate in muscle
- Uric Acid comes from the breakdown of nucleic acids in body cells
What is Urobilin?
- Where is Urobilin derived from?
- A yellowish pigment that is responsible for the color of urine
- The pathway by which hemoglobin is broken down. This pathway involves the SPLEEN, LIVER, AND LARGE INTESTINE.
Give an example of the body being in excess of Electrolytes
- ex: If your body has too many sodium ions, then the excess sodium ions are put into the urine for excretion of the body. If the body does not have enough sodium ions, then little or no sodium ions enter the urine.
What are other Electrolytes that can be present in the urine?
- Potassium ions, Calcium ions, Hydrogen ions, and Bicarbonate ions.
In Summary: The concentrations of water and electrolytes in urine vary depending on what the body needs.
What are Hormones? What’s its quantity?
What happens to any Hormone present in blood?
- Present in very minute (small) quantities in urine
- It becomes part of the urine.Fun fact: That’s why a woman can find out she’s pregnant through a sample of her urine, and then testing it for the pregnancy hormone
Where do Ketones derive from?
What is the amount or quantity of Ketones in Urine?
When or under what conditions does the concentration of Ketones significantly increase?
- Ketone bodies are substances derived from the catabolism of Lipids in Liver cells
- Normally present in Trace amounts. These means that their concentration in urine is so small that you can just barely detect them.
- When a person has Diabetes or is Starving. A high concentration of ketones in the urine causes the urine to have a fruity or sweet odor.
POWERPHYS ACTIVITY
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The formation of urine by each kidney enables the body to regulate blood (water) volume, blood composition and blood pH. In this activity you will examine the effect of fluid intake on urine production.
OBJECTIVES
- Measure urine output and urine and plasma osmolarity (a measure of solute concentration), during different states of hydration.
- Discuss the homeostatic mechanisms involved in producing concentrated and dilute urine.
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Notes from Review
Ideally, daily water intake and water loss should be
equal.
Water Reabsorption by the Nephron:
- What is the functional unit of the kidney? Nephron.
- Normally, how many liters of filtrate do the kidneys
produce? 180L - How many liters of urine do the kidneys produce per
day? 1 - 2 L - How many liters of water are the kidneys reabsorbing
each day? - What percent of water reabsorption by the kidney nephrons is obligatory water reabsorption? 90%
- What percent of water reabsorption by the kidney nephrons is facultative water reabsorption? 10%
The functional unit of the kidney is the nephron.
- Nephron
- 180L
- 1-2 L
- Since the filtrate is mainly water, the nephrons are reabsorbing about 178-179 liters of water each day
- 90%
- 10%
worded: Each nephron filters blood and modifies that filtrate, via the processes of reabsorption and secretion, to form urine. Normally the kidneys produce 180 liters of filtrate but only 1 — 2 liters of urine per day. Since the filtrate is mainly water, the nephrons are reabsorbing about 178-179 liters of water each day. 90% of water reabsorption by the kidney nephrons is obligatory water reabsorption while only 10% is facultative water reabsorption.
Antidiuretic Hormone - ADH
- What does ADH do? function?
Regulates body water content - What happens if there is no ADH?
No Facultative Reabsorption & production of larger
dilute urine - What controls ADH’s secretion? Negative Feedback
- What happens when plasma osmolarity increases
even in the slightest?
-
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- Antidiuretic hormone (ADH) regulates body water content by controlling facultative water reabsorption. ADH increases the water permeability of the last part of the distal tubule and of the collecting ducts. Water reabsorption from the filtrate increases, resulting in a smaller volume of concentrated urine and less water loss in urine.
- The absence of ADH results in no facultative reabsorption of water and the production of a larger volume of dilute urine and greater water loss in urine.
- ADH secretion by the posterior pituitary is controlled by Negative Feedback.
- ADH is secreted in response to an increase in plasma and interstitial osmolarity (decrease in water content).
- When plasma osmolarity increases by as little as 1%, osmoreceptors in the hypothalamus respond by sending nerve impulses to the posterior pituitary resulting in the release of ADH.
- ADH causes facultative reabsorption of water resulting in a decrease in plasma osmolarity and a decrease in ADH secretion.
Measurement of Osmolarity
- What is used to measure plasma and urine osmolarity?
Osmometer - How does an osmometer work to measure osmolarity?
Freezing Point Depression
- Plasma and urine osmolarity is measured with an
osmometer.- An osmometer uses freezing point depression to measure osmolarity.
Fun Fact: Substances that have a high osmolarity freeze at a lower temperature than water.