Limited time offer 20% OFF StudySoup Subscription details

CSU - BC 103 - Class Notes - Week 17

Created by: Caroline Hurlbut Elite Notetaker

> > > > CSU - BC 103 - Class Notes - Week 17

CSU - BC 103 - Class Notes - Week 17

0 5 3 35 Reviews
This preview shows pages 1 - 2 of a 3 page document. to view the rest of the content
background image Osmoregulation & Excretion osmosis requires semi-permeable membrane hypertonic solution - higher solute concentration, lower H2O concentration —>desiccation of cell hypotonic solution - lower solute concentration, higher H2O concentration             —>swelling of cell isotonic solution - same concentration of solute/H2O on both sides of membrane net movement of water is toward more solute ex. marine fish are hypotonic to sea water and sea water is hypertonic to marine fish osmoconformers vs osmoregulators  osmoconformers: isoosmotic with environment but differ in specific solutes in  tissues (mostly marine invertebrates)  osmoregulators: expend energy to control water uptake or loss in hypo/ hypertonic environment (all other aquatic animals)  marine vs freshwater osmoregulation —marine fish are hypoosmotic to environment and must expend energy to lose  salt/ions and avoid water loss —freshwater fish are hyperosmotic to environment and must expend energy to  lose water and avoid solute loss terrestrial animals - challenge is desiccation —have body coverings and use physiological and behavioral mechanisms to  avoid water loss —3 ways to get water A. ingest it from food
B. drinking free water
C. metabolic production (cellular respiration)
—3 ways to lose water A. gas exchange (lose water through moist epithelia)
B. urination and defecation (lose nitrogenous wastes)
transport epithelia - specialized cells for moving particular solutes into/out of body 
(ex. salt glands and kidneys)
nitrogenous wastes created by metabolism of proteins —must be excreted in solution—>water loss
—nitrogen removed in the form of highly toxic ammonia, can be transformed into 
urea or uric acid (low toxicities and require less water to excrete, but also require more 
waste products depend on phylogeny and habitat —most aquatic animals produce ammonia
—mammals and most amphibians produce urea
—most reptiles produce uric acid
excretory process —filtration: body fluid comes into contact with transport epithelium membrane  and hydrostatic pressure drives water and small solutes across membrane (filtrate) —reabsorption: valuable molecules actively transported back into body fluids
background image —secretion: additional wastes actively transported into waste fluid
—excretion: fluid wastes removed from body
excretory system in mammalian kidney —kidneys: set of tubes that create large surface area for exchange of water and  solutes via transport epithelia —kidneys receive blood from renal vein, most blood is filtered and reabsorbed  into blood fluid, remaining fluid leaves body as urine tubules arranged into nephrons, where filtration, reabsorption, and secretion occur Glomerulus and Bowman’s capsule: filtrates collected
proximal tubule: valuable molecules transported out of filtrate and reabsorbed
loop of Henle 
A. descending limb: water flows out of filtrate
B. ascending limb: solutes move out of filtrate into medulla, filtrate 
becomes more dilute as it ascends distal tubule: regulates K+ and NaCl concentration in body fluids via  reabsorption and secretion collecting duct: water flows out of filtrate and travels back through medulla flow of water through kidney creates concentration gradient types of nephrons cortical: reach short distance into medulla
juxamedullary: extend deep into medulla, critical for concentrating urine

This is the end of the preview. Please to view the rest of the content
Join more than 18,000+ college students at Colorado State University who use StudySoup to get ahead
School: Colorado State University
Department: Biology
Course: Biology of Organisms-Animals and Plants
Professor: Jennifer Dewey
Term: Fall 2016
Name: Life 103 Week 13
Description: Methods of gas exchange, osmoregulation and excretion, and the excretory process in mammalian kidneys.
Uploaded: 04/22/2016
3 Pages 26 Views 20 Unlocks
  • Better Grades Guarantee
  • 24/7 Homework help
  • Notes, Study Guides, Flashcards + More!
Recommended Documents
Join StudySoup for FREE
Get Full Access to CSU - LIFE 103 - Class Notes - Week 17
Join with Email
Already have an account? Login here
Log in to StudySoup
Get Full Access to CSU - LIFE 103 - Class Notes - Week 17

Forgot password? Reset password here

Reset your password

I don't want to reset my password

Need help? Contact support

Need an Account? Is not associated with an account
Sign up
We're here to help

Having trouble accessing your account? Let us help you, contact support at +1(510) 944-1054 or

Got it, thanks!
Password Reset Request Sent An email has been sent to the email address associated to your account. Follow the link in the email to reset your password. If you're having trouble finding our email please check your spam folder
Got it, thanks!
Already have an Account? Is already in use
Log in
Incorrect Password The password used to log in with this account is incorrect
Try Again

Forgot password? Reset it here