Excretion Flashcards
Two waste gases that plants produce
Oxygen- as a product of photosynthesis
Carbon dioxide- as a waste product of respiration
What do the kidneys do
- to regulate volume and concentration of urine
- remove waste and regulate body water content
general structure of kidney
-contains cortex and medulla
-renal artery carries blood to kidney
-renal vein carries blood away from kidney
- each kidney contains nephrons
- renal pelvis where urine made in the nephron drains into
-the ureter carries fluid from kidneys to the bladder
3 waste products produced in the body
- Urea
-carbon dixide
-excess salt and water
3 excretory organs
-lungs
-kidneys
-skin
role of ureter
Carries urine from the kidneys to the bladder for excretion
nephron parts
-glomerulus
- the bowmanns capsule ( which covers the glomerulus- the cup thing)
-proximal convoluted tubule
-loop of Henle
-Distal convoluted tubule
-collecting duct
urethra
leads bladder out of the body
Ultrafiltration
removes all small molecules from the blood including glucose,water ,mineral ions and urea. The large cells and protein are too big and so stay in the blood.
process of ultrafiltration
- Blood enters kidney through the renal artery into arterioles
- the arteriole to the glomerulus is smaller than the arteriole away meaning higher pressure
- forces fluid through capillary wall and the basement membrane to form glomerular filtrate in the Bowman’s capsule
components of glomerular filtrate
- urea
- salts
- water
- glucose
selective reabsorption
movement of different amount of substances into the blood to prevent excretion of useful substances like glucose which provide energy.
ADH
Antidiuretic hormone
when is ADH released
when the body lacks water
How does ADH affect the collecting duct?
makes the collecting duct more permeable to water so that more water is reabsorbed from the filterate
what is excretion?
Removal of METABOLIC waste
negative feedback loop when dehydration is detected
-thirst signals activated
-more ADH released (water retained by kidneys)
- urine is less dilute and has a smaller volume as a result and is more concentrated
Describe negative feedback loop when overhydration is detected
-less ADH is released
-Dilute urine is made
- salts are retained
Componets of urine
-water
-urea
- ions
test for protein
Biuret
Test for glucose
Benedicts
put in 60-70’c heat for 5 minutes
Osmoregulation
Keeping the water and salt content of internal environment constant
Where is ADH produced from?
pituitary gland
Where does ultrafiltration happen?
Bowmanns capsule
