Question | Answer |
What does not happen during excretion? | no filtration |
What organ do vertebrates have for osmoregulation and excretion? | kidneys |
How does the anatomy work? | Urine passed into ureter that leads to urinary bladder.
-emptied through urethra. |
What is the outer region of kidneys called? What's the inner? | Cortex, medulla |
What are nephrons? | Individual units of kidneys, coiled up. |
What are the 2 types of nephrons? | cortical nephrons
juxtamedullary nephorns. |
Where does the filtration of blood occur? | glomerulus. |
What does Bowmans capsule do? | surround glomerulus. |
How will filtrate travel? | proximal tubule-down&up loop of henle-through distal tubule-> drain through collecting duct. |
Whats step 1 in filtration? | blood pressure forces stuff out of glomerulus in Bowmans capsule. |
Step 2&3 in reabsorbtion and secretion? | filtrate enters proximal tubule; Na+ pumped out. |
4 steps of excretion? | 1. filtration- water, amino acids etc, filtered out.
2. reabsorbtion-not wasted things are reabsorbed.
3. secretion- access is added to filtrate.
4. excretion- filtrate is expelled from body. |
What invertebrates have excretory systems? | protonephridia in plathyhelmentes. |
What excretory system is in mollusca? | metanephridia, ciliated opening drains fluid from coelom. |
What do insects produce? | malphigian tubule- connect excretory system to tigestive tract. |
What is urine concentration controlled by? | hormones. |
What does Aldosterone cause? | distal tubules to release more salt than H2O. |
What is not reduntant? | ADH& RAAS |
Where is urethra in males? | Penis |
Where is urethra in females? | has it's own opening. |
What do kidneys spend more off than most organs? | energy |
What are the steps once filtrate enters loop of Henle and does down? | environment gets progressively more hyperosmotic.
-epithelial walls are permeable to H2O but not salts.
-H2O leaves filtrate through aquaporin channels. |
What happens on ascending limb in loop of henle? | environment gets progressively more hypoosmotic.
-walls are permeable to salt but not H2O.
- salt diffuses.
-filtrate become more diluted. |
What happens in the situal tubule? | a lot of selective transport. |
What happens in collecting duct? | H2O is absorbed, but how much depends on hormones. |
What happens in step 4, excretion? | the renal pelvis collects urine
-urine flows through ureters-> urinary bladder-urethra. |
What are nephron types? | juxtameduallary (go deeper in medulla) |
When blood pressure drops, cells release? | ranin, interacts with angiotensin, decreasing blood flow. |
What does 2nd hormone system monitor? What is used? | blood pressure, aldosterone (RAAS) |
What happens if blood osmolarity drops? | less ADH is release, more dilute urine. |
Where do we find increased numbers of aquaporin channels? | collecting ducts of nephrons. |
What happens if osmolarity of blood rises? | ADH is released. |
What's produced in the hypothalamus? | anit-diuretic hormone (ADH). |
What are the 3 types of nitrogen waste from ammonia? | 1. ammonia
- cheap, but very toxic (needs lots H2O) aquatic animals.
2. Urea
- less cheap& less toxic (amphibians, mammals)
3. Uric acid
- least cheap, not toxic (birds&reptiles) |
In what chemical form is the waste? | ammonia (NH3) |
What do animals produce? | nitrogenous waste, from breakdown of proteins, nucleic acids. |
What does osmoregulation cost a lot of?
What is the specialized tissue called? | energy expensive& transport epithelia |
What 2 ways can animals loose H2O? | Urine&feces, evaporation across skin |
What are 3 ways land animals gain water? | drinking, eating, byproduct of mentabolism. |
What risk to terrestrial animals face? | dehydration. |
What did the water bear develop? | anhydrobiosis. he can loose 98% of water. |
What problem do fresh water fish have? | their tissues are hyperosmotic to water (take in a LOT of H2O) |
What's special about sharks? | their tissue stores high amounts of urea. TMAO which protects against urea. |
What is an osmoregulator? | maintainging an osmolarity different than seawater. |
What is a stenhaline environment? | When the animal lives in either salt or fresh water. |
What does a euryhaline environment mean? | Where fresh and saltwater meets. |
What do you call an animal that keeps internal osmolarity the same as environment? | Osmoconformers. |
An equal amouint of solutes? | isoosmatic. |
Few solutes? | hypoosmotic. |
many solutes? | hyperosmotic. |
Where does H2O want to move during osmosis? | towards area of higher osmolarity. |
systems for what are compled to osmoregulation? | systems for excretion. |
What is one of the most important aspects of homeostasis? | osmoregulation. |
What balance do metabolic reactions require? | water and ions. |