06.01 EXCRETORY SYSTEM
Mrs. Jessica Romito
SUMMARY, OBJECTIVES, AND STANDARDS
Review module
Review assessment
By the end of this class you will
STANDARDS�SC.912.L.14.47: Describe the physiology of urine formation by the kidney.��
URINARY FUNCTION
Urine made by the kidneys
Drains to
Bladder for temporary storage
Anything less than 800mL
600-800mL for an adult
Reaches capacity at/urge to urinate/unconscious control
Conscious control
More on the capacity of the bladder with references
THE KIDNEYS
FUNCTIONS:
MAIN FUNCTIONS:
NEGATIVE FEEDBACK LOOP
The regulation of water content takes place in the kidneys and is under the control of a hormone called ADH, antidiuretic hormone. Like most homeostatic mechanisms, the maintenance of water balance involves negative feedback.
URINE FORMATION
When the body is short of water, the HYPOTHALAMUS responds in two ways.
It's the kidneys' job to FILTER the blood and REGULATE its water content.
OSMOREGULATION
URINE FORMATION
It's the kidneys' job to FILTER the blood and REGULATE its water content.
URINE is a watery fluid that's produced in the kidneys.
Click here for a nice review of the anatomic structures for urine formation
URINE FORMATION
The urine trickles down the URETERS or tubes, connecting the kidneys to the bladder.
As more urine collects, the bladder expands.
The major waste product in urine is UREA.
It is formed in the liver from the breakdown of PROTEINS, which is not required by the body.
URINE FORMATION
The urea is transported in the blood to the kidneys.
Here it’s REMOVED and mixed with water and other substances removed from the blood to form urine.
There are millions of NEPHRONS in the kidney.
They are responsible for removing urea from the blood.
They are cleaning structures.
URINE FORMATION
Blood entering the kidney | Blood leaving the kidney |
High in urea | No urea |
High in oxygen | Low in oxygen (due to cell respiration) |
No carbon dioxide | High in carbon dioxide (due to cell respiration) |
Glucose levels high | Glucose present but lowering in concentration. (due to cell respiration) |
URINE FORMATION
Blood reaches the GLOMERULUS, where the narrow vessels create an area of relatively high pressure.
This forces the fluid part of the blood through the walls of the GLOMERULUS capillaries.
Blood cells and proteins are too large to pass through and remain in the blood, but the fluid passes through.
URINE FORMATION
The filtered fluid, or filtrate, trickles along the RENAL TUBULE, where much of the water, glucose, and salts are reabsorbed, ensuring the blood maintains its correct composition.
The toxic urea is left in the fluid.
URINE FORMATION
The remaining fluid then trickles into the collecting ducts and finally into the ureters.
Now called urine, it passes down the ureters and drips into the BLADDER.
ASSIGNMENT 06.01
Use the Urine Formation worksheet from page 2 of the module (went over the answers in this class).
Be able to fill in this table:
Component | Do you know… | Function |
ADH | Location? | |
Hypothalamus | Location? | |
Liver | Structure? | |
Nephrons | Structure? | |
Pituitary | Location? | |
Urea | Location? | |
Renal Tubule | Structure? | |
Glomerulus | Structure? | |
ASSIGNMENT 06.01
ASSESSMENT
Create a flow chart to represent and describe the process of urine formation in the kidneys. You can use any flow chart format that you wish but you must include the components below:
Keep in mind: the process of urine formation is NOT linear because there are multiple components involved, ie the brain, liver, and kidneys
This will affect your flow chart design.
Contact Information
Mrs. Jessica Romito
Phone Number: +1 (301) 485-9114
(text/call/WhatsApp)
Email: jromito@laurelsprings.com
Monday–Friday 8 am to 11 pm Eastern Time�5 am to 8 pm Pacific Time