Chapter 48 Osmoregulation

Fluid makes up what percentage of our body

45-75%, this is affected by age and tissue ratio (adipose to skeletal ratio)

Rank the ages that have the most to the least amount of body make up from fluid

infants>young>elderly

What percent of skeletal muscles is water

75%

Filtrate vs urine

Filtrate: urine which is able to be modified

Urine: cannot be modified anywhere

Do we lose muscle mass when get older?

yes

What percentage of water is adipose tissue

20%

Why is having alot of adipose tissue bad

makes you more susceptible to fluid imbalance

What percent of fluid is found intracellulary

around 60-65% (majority of fluids in the body found intracellularly)

How is extracellular fluid split

Majority and can vary: interstitial fluid (32%) and blood plasma (8%)
Minority and is static: synovial fluid, eye fluid, CSF, inner ear, and serous fluid

How is interstitial fluid formed

by blood plasma

what is plasma

medium of blood which transports: gases, waste products and

When we eat something salty, water comes from what to balance the salt levels

interstitial fluid.

What are the main electrolytes we look at

Na+, Cl-, Mg+2

What is osmosis

the movement of water (it follows ions) through a selectively permeable membrane

Wha pressure does osmosis create

osmotic pressure

What is osmotic pressure

Pressure exerted on hypertonic side of membrane to prevent movement of water from hypotonic side

How does the kidney help with osmoregulation

reclaim ions or get rid of them

What is osmoles

number of particles/L of solution

How much Osmoles are produces when 1mol NaCl is dissolved

1 mol of Na+ and 1 mol of Cl- so two osmoles

If we regulate particle number (osmoes) we must also regulate

water

To control water level what do we move

anything dissolved in water

What is a major macromolecule which is metabolized and what is the waste product

protein and nitrogenous wastes

What molecules/products are seen in the byproduct of metabolism

H2O, CO2, and nitrogenous waste

What are the major processes the kidney is involved in

pH regulation: metabolic regulation
RBC production: Erythropoietin
Blood pressure regulation: Reinin-aldosterone-angiotensin pathway

What are the nitrogenous wastes

Ammonia, Urea, and Uric acid

Main way nitrogenous waste is excreted

The kidney

Why is the kidney involved in the blood cell production

it’s a major user of oxygen

What nitrogenous waste needs the most energy to be produced

1) Uric Acid
2) Urea
3) Ammonia

The more energy a nitrogenous waste is needed produced the___ is needed to excrete

less water

How do we get rid of ammonia

it enters the liver to be apart of the urea cycle (MAMMALS)

What is the use of Urea

it actually helps establish an osmotic gradient in the interstitial fluid and maintain cell volume

What is so dangerous about uric acid

it precipitate in water to form crystals which can cause gout
(due to, to much uric acid and typically seen around joints)

What animals produce uric acid

animals found in the desert and birds
(due to low levels of water)

What animal makes ammonium

basically every animal, as long as you have access to water you can make ammonia
(aquatic or terrestrial dwellers)

How is creatinine produced

from creatine metabolism in muscle, the metabolism uses a nonprotein source

What is creatinine

waste product and it’s only secreted

What is the characteristic of ammonia’s toxicity

highly toxic it can disrupt pH and chemical reaction

Who can produce urea

aquatic and terrestrial animals, all animals that have access to water

What is the characteristic of urea’s toxicity

less toxic than ammonia it can interfere with chemical reactions, it’s still toxic to cells must animals have evolved to get around the toxicity

What animal habitat produces a lot of uric acid

habitats with limited/no access to water: terrestrial dwellers and shelled embryos

What is the characteristic of Uric Acid toxicity

least toxic, but it’s secreted as semisolid paste or dense pallets

What animals are seen to secrete uric acid

reptiles, birds, insects, some species of arboreal frogs, and cockroaches

What do cockroaches do with uric acid

recycle nitrogen source when on a low protein diet to retain water

What is osmoconformer

They are isotonic with the environment, (REDO)

What animals are osmoconformer

mainly invertebrates (star fishes, crabs, jelly fishes, lobsters)
sharks, skates and hagfish

Osmoregulators

maintains H2O and ionic composition independent of the environment, (REDO)

What animals are typically osmoregulator

vertebrates
marine invertebrates living in costal lagoons and estuaries.

What are two ways animals with no multicellular excretory structure regulate osmotic pressure

via organelles like contractile vacuoles
via specialized glands like renette glands

How are protists omsmogregulators

They have contractile vacuole to regulate water content, to result in regulation of osmotic pressure

How do nematodes go through ostomicregulation

they have a renette glands

How does renette gland work

they take up fluid, MAY get some ion regulation, it is not organized into the kidney and could be stand alone or connected by tubules.

the fluid goes to the body surface and leaves (ions may leave with fluid)

Where have seen something like the renette gland before

the antennal gland in crustascens (crayfish)

nephridia meaning

relating to kidney like structure

What type of animals have nephridial organs

invertebrates

What does nephridial organ do

seen in osmoregulation and excretion

What is the structure of nephridial organ

they are simple or branching tubules which is connected to the nephridiopores

What is nephridiopores

a surface opening found in invertebrates

Two types of nephridial organs found in invertebrates

protonpehridia and metanephridia

What animals have protonephria

acoelamtes and coelomates, platyhelminths and some annelids

(INSECTS)

If we want fluid to keep leaving a pore we need…

a current (seen in protonephrida, metanephridia and us)

What are the structures/characteristics involved with protonephridida

tubules, flame cells, excess fluid, hypoostmoic urine
closed internally by flame cells

What is the tubule structure characteristic of protonephridia

they have interstitial flame cells on the end of tubules and internal cilia which propel intersistial fluid into tubules

What do the flame cells in protonephrida do

they create a current, because they have cilia which beat to draw water in tubule

What is the placement of flamecell

hanging into the lumen, it has slit like openings with cilia that hangs down

What does the slits in the flame cells do

they act as hole to move interstitial fluid into excretory duct

In protonephridia is the fluid inside the tubule filtrate or urine

filtrate

In protonehphrdia how does urine leave

through the nephridapore

What is the composition of protonephrdia urine/waste

it is hypoostmic and most of their nitrogenous waste leaves across body surface

What kind of animals have a metanephridida

most annelids, mollusks and crustaceans, and coelomates

How is the tubule structure of metaphridida

it is open to the inside and outside end of the nephrdidapore

How is the current created in metanephridida

they have a funnel cell structure

What is the characteristics of funnel cell structure

open into intersititum and found on end of tubules they have cilia that extends out from the internal opening

What does the cilia do in the funnel cells structure of metanephridia

they beat to draw fluid into tubule

What is around the tubule of metanephridia

circulatory system which is able to add or take out things from the filtrate

What happens with when there is excess fluid in metanephrida

it still goes into the tubules but solutes from the coelem goes into the nephridpore

What does circulatory system around tubules in metanephridia allow for

for urine to be hypotonic, isotonic, and hypertonic

What is odd about metanephridida

there is intake of fluid one segment and modification in another segment

Insects have what kind of tubules

Malpighian tubules

Where is the malpighian tubules located in sects

intersititum and it extends from the gut wall and it closed to the interstitium

There is no cilia in malpighian tubules so how do we create a current

by moving ions into tubules so that water follows

How does the mapighian tubules work

ions (K-, Cl-) and uric acid is transported into lumen (via a pump) the lumen is now hypertonic so water follows, fluid is then modified (to a pallet due to pH) and passes along tubules, which it empties into gut where cells in the rectum can modify it

What kind of circulation does the mapighian tubules and gut have

counter current

What does impact on counter current flow of malpighian tubules and gut

water can be taken up from the gut

What kind of urine can malpighian tubules produce

all 3 types, hypotonic, isotonic, and hypertonic

All vertebrates have what type of osmoregulation and excretion

the same as us

In vertebrates what does the kidney do

main osmoregulatory and excretion organ,

we do have other structures which can excrete waste product it’s not the major one

How does kidney produce waste product

producing urine

How does digestive system get rid of waste product

through feces

How doe skin get rid of waste product

sweat

How do lungs get rid of waste products

exhaling air which contains water vapor and carbon dioxide

What is within the sweat that we excrete

water, ammonia, urea, and salt

A freshwater fish is what to their enviorment

hypertonic

The largest exposed surface to water of a fish

the gills

What does gills do in fish

we gain alot of water via osmosis but the gills help us with ion regulation

What does kidney of freshwater fish produce

large volume of dilute urine which is 10% nitrogenous waste

How does water move in freshwater fish

it moves inside of them but they are not drinking it, this cause a very dilute urine, and urine is hypertonic to the cell

(any water needed is taken up by the gills)

In saltwater fish what is the fish to the enviorment

hypotonic

Since we lose water to the environment what is the kidney production level

produce very little amounts of urine which is isotonic and it has small or no glomeruli