Lecture 28: OVERVIEW AND GROSS STRUCTURE OF THE KIDNEY Flashcards
What portion of a male is water?
60%
What portion of a female is water?
55%
What is the reason for the differences in water content between males and females?
Males have more muscle which holds water while females have more adipose which holds less water
What is the total body water made up of?
1/3 extracellular fluid and 2/3 intracellular fluid
What is crucial?
Balance of water (and solutes) in the body
How does the urinary system maintain balance?
By filtering the blood and expelling:
- excess water
- excess salts
- wastes of metabolism
- many toxins and drugs
How much blood flows through the kidney per minute?
1200 ml
How much urine is produced by a typical person in a day?
800-2000ml
What is urine?
Waste product excreted to maintain balance within the body
What is found in normal urine?
Water, salts, urea, metabolites, hormones and small proteins
Is urine pH regulated?
No, not tightly (4.6-8) as it is influenced by what is being excreted
What is urine useful for?
A diagnostic tool for disease states
What is in abnormal urine?
Large proteins (too big to be filtered), RBC’s (too big to be filtered) and glucose (filtered but completely reabsorbed)
What does the urinary system need to be effective?
- delivery system for blood
- selective filtration system (based largely on size)
- filtrate recovery mechanism (reabsorption)
- system to return recovered, filtered fluid to the body
- system to remove filtrate from the body
- protection
- ability to communicate with relevant parts of the body
- adaptable to meet the body’s changing needs
What are the main components of the urinary system?
2 kidneys, 2 ureters, urinary bladder and urethra
What does the structure of the kidney allow?
- blood to be brought into close proximity with the nephron for filtering
- blood that has been filtered to leave the kidney
- a pathway for urine to be removed from the kidney, stored and then excreted
- protection
What vertebra are the kidneys between?
T12 and L3
What ribs are the kidneys near?
11th and 12th
Where does the convex side of the kidney face?
Laterally
What does the medial surface of the kidney have?
A concave notch called the hilum