Kidneys & Homeostasis Flashcards
What is homeostasis
Homeostasis is the maintenance of a constant internal environment
What are some conditions that must be kept constant within the body
- blood glucose
- core body temperature
- blood solute potential.
Why is homeostasis important
Homeostasis is important so that cells can function efficiently even if:
* external conditions fluctuate
* the body has different levels of
activity
What is negative feedback
Negative feedback is a system that restores conditions to a set point when it detects a deviation. This results in narrow fluctuations around the set point
How does negative feedback work
Each condition has a set point. Deviations are detected. A control centre sends impulses to an effector (muscle or gland), which returns conditions to the set point – this is negative feedback
What are the three main visible parts of the kidney
- Cortex
- Medulla - organised into triangalur renal pyramids
- Pelvis
What artery supplies the kidney
Renal Artery
What transfers urine to the bladder
The ureter
Where are the glomerulus, Bowman’s capsule, pct and dct located
The Cortex
Where are the loop of henle and the collecting duct located
The Medulla
What is ultrafiltration
Blood is filtered in the glomerulus and Bowman’s capsule under pressure
Which small molecules are forced out of the glomerelus
water, glucose, salts and urea
What are the filtering layers at the Bowman’s capsule
- Fenestrations between epithelial cells of capilliary
- Pores in the basement membrane - molecular seive
- Filtration slits in the podocyte cells
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