Water Balance In Animals

1. Keep in mind the concepts of osmolarity and tonicity. There will be another osmolarity problem on the final.

A) Osmolarity is the measure of resistance of a solution to flow freely due to the presence of solutes.

C) Osmolarity and tonicity are terms that can be used interchangeably to describe the concentration of solutes in a solution.

B) Tonicity is a measure of the color intensity of a solution based on the concentration of solutes.

Osmolarityis an easily measurable characteristic, by e.g. freezing pointdepression.In simple terms it is the total concentration of solutes(includingions) in a solution, and this does not depend on whether thesolutescan cross cell membranes or not. Tonicity relates to the osmoticGRADIENTdue to solutes that affects a semi-permeable membrane ( i.e.amembrane that is permeable to water); ONLY solutes that do not crossthemembrane contribute to this effect.

Osmolarity and tonicity are distinct concepts that have specific definitions and applications in understanding the behavior of solutions in different contexts. It's important to differentiate between these terms in order to accurately interpret and analyze the characteristics of a solution.

Explanation

Osmolarity and tonicity are distinct concepts that have specific definitions and applications in understanding the behavior of solutions in different contexts. It's important to differentiate between these terms in order to accurately interpret and analyze the characteristics of a solution.

2. We covered three major environments - marine, terrestrial, and freshwater. Explain what problems animals face in each, in terms of ion and water balance. Which one is the birthplace of animals? Which is the birthplace of vertebrates?

Fresh water- about 100 mOsm

Terrestrial- Land. Losing air and water through mouth.

Marine- salt water about 1000 mOsmAnimallife probably evolved hereish is constantlylosing water through osmosis This can beminimized by waterproofing the fish through skin, mucous layer, scalesCannotminimize water loss through gills, skin, digestive systemHow can we gainwater back?Eating,drinking but gain saltFishhas to find a way to get rid of salt Don'tproduce very much urine b/cuz Constantlydehydrated Fresh water- about 100 mOsmVertebratesevolved hereDon't drink waterProduce copiousdilute urineMain problem is lossof ionsUse gills to getions back Terrestrial- LandLosing air and water through mouth

Marine- Animals drink water constantly losing water through osmosis.

3. How do fish cope with the problems of freshwater and saltwater?

Lose salt throughthe gills; pumps send salt outThey drink the waterand they have salt glands orpumps which pump salt out of the creature and on to the skinMarine mammal -exceedingly good kidney to get rid of salt or it never drinks; dietary water; very good at conserving water
Water uptake by osmosis and ion active uptake in gills

Fish have specialized organs that produce salt to counteract the effects of freshwater or saltwater

Fish absorb salt through their skin and gills, helping to maintain balance

Fish rely solely on their external environment to regulate salt levels without any internal mechanisms

Fish have developed various mechanisms to cope with the challenges of living in freshwater and saltwater environments, including regulating salt levels through gills, drinking water, using salt glands or pumps, and having specialized kidneys. The incorrect answers do not accurately reflect the common strategies employed by fish.

Explanation

Fish have developed various mechanisms to cope with the challenges of living in freshwater and saltwater environments, including regulating salt levels through gills, drinking water, using salt glands or pumps, and having specialized kidneys. The incorrect answers do not accurately reflect the common strategies employed by fish.

4. Identify the correct label for the parts of a nephron.

SUNGLASSES

UMBRELLA

PICTURE

BANANA

The correct answer to label the parts of a nephron is 'pICTURE'. This is a common mnemonic device used to remember the parts of a nephron - proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting duct.

Explanation

The correct answer to label the parts of a nephron is 'pICTURE'. This is a common mnemonic device used to remember the parts of a nephron - proximal convoluted tubule, loop of Henle, distal convoluted tubule, and collecting duct.

5. Explain why nitrogen excretion is a problem, and the three ways animals solve it. Why is nitrogen excretion not a problem for plants?

If you have an aminoacid you can uses it for energy or other purposesNH2 is difficult tolet go of because it may produce nh3 in the blood which is toxicPlants can turn nh3back into amino acidsTo get rid ofammonia dissolve it in water to get rid of itFish: to get rid of1 g of ammonia 300 ml of h2o is neededMammal: to get ridof 1 g N 50 ml of h2o is needed (needs ATP)Uric acid is reallytoxic and not soluble in water To excrete 1g Ntakes less than 10 ml water

To excrete nitrogen, animals only require minimal amounts of water which makes the process efficient.

Nitrogen excretion is not a problem for plants because they do not produce ammonia as a byproduct of metabolism.

Animals excrete nitrogen by converting it into a gas and releasing it into the atmosphere.

The correct answer explains the challenges of nitrogen excretion for animals and the specific mechanisms they use to solve it, highlighting the differences between animals and plants in this regard.

Explanation

The correct answer explains the challenges of nitrogen excretion for animals and the specific mechanisms they use to solve it, highlighting the differences between animals and plants in this regard.