Osmoregulation Flashcards
Osmoregulation is a strategy that animals have to….
control ion and water balance
How do animals ensure that the properties of their extracellular fluids keep their cells happy?
osmoregulation
What is a solution?
combos of solvent (usually water and solutes)
what is the difference between molarity and osmolarity?
molarity: levels of a PARTICULAR solute
osmolarity: lumps ALL of the different solute and gets a different total (it is not particular)
Semipermeable membrane permit the movement of ___________ but not _________?
water, solutes
When two compartments are seperated by an osmotic gradient there is a tendacy for what?
to move around and neutralize those gradients
What is the osmotic pressure?
a force that it produced from the movement of water in response to osmotic gradients
When would the movement of solutes stop with a osmotic gradient?
once the osmotic pressure forcing water to the higher osmolarity equals the force of gravity trying to make the two sides the same
What matters to the cell is _______ not ________?
tonicity, osmolarity
Hyportonic solutions cause a cell to ______?
swell
Hypertonic solutions cause a cell to _______?
shrink
Describe tonicity.
describes the effects of a solution on a cell’s volume
Isosmotic means?
a solution having the same osmotic pressure as blood, when the osmolarity outside of the cell is equal to the osmolarity inside the cell (cell is isosmotic to the solution and solution is isosmotic to the cell)
You always talk about what a _______ does to a cell?
solutionn
tonicity always refers to the _______ around the cell
solution
what does hyperosmotic mean?
when extracellular fluid osmolarity is greater than that of the intracellular fluid
wha does hypoosmotic mean?
A solution will be hypertonic to a cell if its solute concentration is higher than that inside the cell, and the solutes cannot cross the membrane
In your tissues, the osmolarity of your blood and extracellular fluid, including interstatial fluid, is the same as…..?
the osmolarity of your cells
higher osmolarity outside the cells would……?
draw water from the cells
What would happen if cells were to shrink?
it would pull the cells away from each other, and tear their protein-protein connection and result in tissue damage and loss of integrity of the epithelial cells
Drinking too much water means your cells would find themselves in what type of solution?
hypertonic
What would our cells being in a hypertonic solution for too long cause?
cause the blood vessels and cells to be deprived of blood flow
What is ECF?
extracellular fluid
Osmoregulation is about how animals control ______ and _______ movement in and out of its ________?
ion, water, ECF
Why do animals that live in the intertidal regions of the ocean experience very rapid changes in osmolarity?
effects of the sun evaporating or being dilutes
A salt water fish is in a __________ environment
hypertonic
A fresh water fish is in a ___________ environment
hypotonic
Both fresh and salt water fish have similar tissues that control ion and water movement but their movements go in __________ directions.
opposite
Salt water fish need to get rid of _______?
salt
Fresh water fish need to obtain _______ and get rid of excess ________
ions, water
Epithelial tissues are involved in what type of movement? give an example of some epithelial tissues
involved in ion movement, found in gills, kidneys, and the intesine
The main difference between fresh water fish and salt water fish is…..?
which transporter they express in which of their tissues
What are osmoregulators?
animals that are able to maintain a constant internal osmolarity in the face of a changing external osmolarity
What are osmoconformers?
they permit their internal osmolarity to change in response to external osmolarity
What is an animal that is a Eurahyaline?
animals that can tolerate wide ranges in external osmolarity (means can tolerate many salts)
What is an animal that is a Stenohaline?
can only live in narrow ranges of salts
What do the terms euryhaline and stenohaline report on?
the tolerance to external changes, not what is going on internally
Salmon in preparation for their transition from fresh water to salt water do what?
-completely remodel their tissue
-gills, kidneys, and intestine convert from ion collectors to ion excreters by replacing ion transporters and altering the cellular composition
What are transport epithelia?
externally facing tissues with the main job of moving ions in and out of the body (ex. gills, lungs, kidneys, intestine)
What do cells that are required for transport all have in common (4 characteristics)?
-polarity in transporters
-tight cell to cell connections
-diverse cell types
-abundant mitochondria
What do polarity in transporters mean?
to get transport moving from one side of the cell to the other, you need two different transporters on the two sides: inner basal membrane and the outer apical membrane
Why are tight cell to cell junctions important?
prevent water and ions from leaking
Why are diverse cell types important?
some cells need to specialized for a different type of transport
Why is abundant mitochondria important?
since all of this ion movement requires energy, they usually have lots of mitochondria, for aerobic production of ATP
Describe a flame cell.
-system is composed of one cell that wraps around itself
-makes a tubule
-uses its flagellum to create a current to bring fluids into the tubule
-fluid moves into the tubule and gets collected them excreted from the body
How are flame cells doing the same thing as the kidney?
uses its own version of tubules to collect and fine tune the nature of excess ions and wastes
Describe malpighian tubules.
-long, blunt tubes that connect to the gut
-collect ions from the surrounding interstitial fluid and excrete them via the gut
-excreting water while feeding allows it to compress blood meal into protein meal
Describe the kidney, its general pathway, and function (this is a long one- good luck)
-blood vessels (glomerulus) enter the mouth of the kidney tubule (Bowman’s capsule)
-low molecular weight solutes and fluids leave the body, across and between the endothelial cells (filtration) and drain into a tubule for processing
-fluid moves through the tubule and is modified by the transport epithelia, reclaiming useful molecules from urine and release them into the interstatial fluid to be collected by surrounding blood vessels
*this is missing a lot, but what I reccommend is go through the transcript for full info and be able to look and label and describe a diagram for this
What is the nephron?
A nephron is the basic structural and functional unit of the kidneys that regulates water and soluble substances in the blood by filtering the blood, reabsorbing what is needed, and excreting the rest as urine.
how is the nephron split?
tubules and glomerus
Glomerulus is another word for….?
blood vessels
The proximal tubule is where the _______ goes to once collected by the _______?
fluid, capsule
Describe the peritubular capillaries.
-responsible for maintaining an osmotic gradient that is essential for making urine
-it is a capillary bed that collected the material that has been removed from the tubules as urine is processed
The loop of henle is….?
the proximal tubule that runs down the depths of the kidney then back up near the surface of the kidney
Why are blood vessels in the Bowman’s capsule the size of a capillary?
to maximize movement of fluid from blood to the tubule (but not considered a capillary)
The fluid from the collecting ducts empties into where?
ureter (then sent to the urinary bladder)
in the proximal tube is where you start to recover valuable ______?
ions
the proximal tube can also be the place to remove what?
drugs, excess, and soluble vitamins
Aquaporins and their relatives permit diffusion of _______ and _______?
water, urea
as fluids move into the descending limb of the loop Henle, the only transporters of importance to excretion are _________ _________?
water channels
as water leaves, the osmolarity _________ in the urine, but the deeper you go down into the descending limb the _________ the osmolarity.
increases, higher
The gradient is produced and maintained by the _________ that collect ________ from around the _________
capillaries, fluids, tubule
why do tubules benefit from the gradient?
use them to ensure there is a favorable gradient for water movement until you hit the bottom of the loop
as the tubule goes back to the surface of the cell it no longer makes what? and what does it make instead
-stops making aquaporins
-instead makes transporters needed to recover NaCl
where does fine tuning of the urine occur?
distal tubule and collecting ducts
Why would the distal tubule and collecting ducts be the target of various hormones that govern urine production?
it is part of urine fine tuning
the energy demands of the transport processes (primary and secondary active transport) depend on __________ and _________ _________ created and maintained by interplay ___________ cells of the tubule
electrochemical, osmotic gradients, epithelial
what does the energy demands depend on as well?
the interstitial fluid that contains the recovered material and the blood vessels that carry the recovered materials back to the circulation
the greater the need for water conservation the _______ the loop of _______ which permits formation of ____________ urine
longer, Henle, concentrated
the loop of henle runs through?
the depth of the kidney, from the cortex to medulla, creating and utilizing an osmotic gradient
kidneys?
maintain ion and water balance
what happens when there is an increase in osmolarity in the blood? (when salt in blood is too high)
-water is drawn from the cells, and increases the blood volume
-at tissue level, cells shrink (not good)
-organ level, there is an increase in blood volume which affects blood pressure which effects heart function
the hypothalamus detects this and stimulates secretion of ADH (antidiuretic hormone)
-ADH travels to the kidney (this hormone also increases the ability of collecting ducts to recover water)
-hypothalamus has axons to increase thirst
-and all of this works to restore osmolarity, and this is when the signalling cascade is turned off by neg feedback
When osmolarity is too high what happens?
the hypothalamus detects this and stimulates secretion of ADH (antidiuretic hormone)
what is a duiretic?
increases urine production
what is an antidiuretic?
reduces urine volume
What happens when osmolarity is too high because too much salt was consumed?
-this process is different
-heart notice blood volume increased, sends signals to kidney to get rid of salt
-increased blood volume is sensed by atrium, and experiences more stretching
-causes more blood in heart
-responds by secreting ANP (atrial natruiretic peptide) which increases Na excretion
ADH is secreted from?
posterior pituitary
RAAs pathway allows us to respond to…?
reduced blood pressure that might arise from dehydration (Low blood volume and high osmolarity) and also responds to blood loss (normal osmolarity reduced/lower volume)
when vessels going into glomerulus sense low blood pressure or volume what happens?
they release enzyme renin
what does renin activate?
the peptide hormone angiotensin (which is produced by the liver)
where does angiotensin go to and trigger what?
-goes to adrenal gland
-triggers release of the steroid aldosterone
what does aldosterone do?
go to the kidney, and increase recovery of water and sodium, which increases blood volume and pressure
