Osmoregulation in Fish

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What mechanism do marine fish use to conserve water and remove excess salt?

Producing a dilute urine

Excreting salt through the kidneys

Drinking water and producing a concentrated urine (correct)

Removing salt through the skin

What adaptation allows some aquatic invertebrates to survive in temporary pools with limited water?

Hyperosmotic regulation

Osmosis

Hypoosmotic regulation

Anhydrobiosis (correct)

How do terrestrial animals replace lost water?

Through photosynthesis

By drinking water and eating hydrating foods (correct)

Through the process of cellular respiration

By absorbing water from the air

What type of cells are specialized for moving solutes in specific directions?

Transport epithelia Signup and view all the answers

How do aquatic organisms release ammonia?

Across the whole body surface or through gills Signup and view all the answers

What is the main form of nitrogenous waste excreted by insects, land snails, and many reptiles?

Uric acid Signup and view all the answers

What is the primary function of nasal glands in marine birds?

Removing excess sodium chloride from the blood Signup and view all the answers

What type of environment do freshwater fish live in, and how do they regulate their body fluid?

Hypotonic environment, hyperosmotic regulation Signup and view all the answers

What is the primary function of the glomerulus in the nephron?

Production of a protein-free filtrate Signup and view all the answers

What is the purpose of the descending limb of the loop of Henle?

Permeable to water and impermeable to NaCl Signup and view all the answers

What is the function of the proximal convoluted tubule in the nephron?

Reabsorption of 60% of the filtrate (H2O, glucose, amino acids, and vitamins) Signup and view all the answers

What is the function of metanephridia in annelids?

Filtration of body fluids Signup and view all the answers

What is the function of antennal glands in crustaceans?

Production of a protein-free ultrafiltrate from the blood Signup and view all the answers

What is the function of Malpighian tubules in insects and spiders?

Secretion of insoluble uric acid Signup and view all the answers

What is the function of protonephridia in flatworms and nematodes?

Collecting body fluids through collecting tubules and the action of a flame cell Signup and view all the answers

What is the function of the nephron in vertebrate kidneys?

Filtration, reabsorption, secretion, and excretion Signup and view all the answers

What is the primary function of osmotic regulation in animals?

To regulate the concentration of solutes within cells Signup and view all the answers

Which of the following marine invertebrates is an example of an osmotic conformer?

Spider crab Signup and view all the answers

What is anhydrobiosis, and in which organisms is it commonly found?

A state of dormancy in aquatic invertebrates when water is scarce Signup and view all the answers

What is the primary function of transport epithelia in animals?

To facilitate the transport of solutes and water across the epithelial layer Signup and view all the answers

Which of the following organisms is an example of a stenohaline species?

Spider crab Signup and view all the answers

What is the primary mechanism of nitrogenous waste management in fish?

Gill excretion Signup and view all the answers

What is the primary difference between euryhaline and stenohaline species?

Their tolerance to changes in salinity Signup and view all the answers

Which of the following is NOT a characteristic of hypertonic environments?

Higher water concentration Signup and view all the answers

Study Notes

Osmotic Regulation

Osmosis: movement of water molecules from areas of high water concentration to areas of low water concentration
Environment classification:
- Hypertonic: higher solute and lower water concentration
- Hypotonic: lower solute and higher water concentration
- Isotonic: equal water and solute concentration (ideal for most animal cells)
Osmotic regulation: maintaining an isotonic environment internally

Marine Fish Osmotic Regulation

Hypertonic environment: constant water loss and salt uptake by hypoosmotic regulation
Strategies:
- Drinking water
- Producing concentrated urine
- Excreting salt through gills by active transport

Freshwater Fish Osmotic Regulation

Hypotonic environment: constant salt and mineral loss and water uptake by hyperosmotic regulation
Strategies:
- Drinking limited water
- Producing diluted urine

Terrestrial Animals

Water loss: evaporation, excretion in urine and feces
Water replacement: food, drinking, and metabolic water (from cellular respiration)

Anhydrobiosis

Adaptation in aquatic invertebrates to survive in temporary pools
Example: Tardigrades

Excretory Systems

Transport epithelia: specialized cells for solute movement
Function: regulate solute content of body fluids
Examples:
- Nasal glands of marine birds (remove excess sodium chloride from blood)

Nitrogenous Wastes

Aquatic organisms: release ammonia across body surface or gills
Mammals and adult amphibians: convert ammonia to urea in the liver
Insects, land snails, and reptiles: excrete uric acid

Excretory System Functions

Filtration: filtering body fluids
Reabsorption: reclaiming valuable solutes
Secretion: adding nonessential solutes and wastes to filtrate
Excretion: processed filtrate containing nitrogenous wastes

Invertebrate Excretory Systems

Protonephridia (flatworms, nematodes, rotifers): collects body fluids through collecting tubules
Metanephridia (annelids): more sophisticated system with two openings and blood vessel network
Antennal glands (green glands): reabsorbs salts prior to excretion
Malpighian tubules (insects and spiders): secrete insoluble uric acid

Vertebrate Kidneys

Functional unit: nephron
Physiological functions:
- Filtration
- Reabsorption
- Secretion
- Excretion

Nephron Function

Glomerulus: produces protein-free filtrate
Proximal convoluted tubule: reabsorbs 60% of filtrate (H2O, glucose, amino acids, and vitamins)
Descending limb of loop of Henle: permeable to water and impermeable to NaCl

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Learn about the osmoregulatory mechanisms of marine and freshwater fish, including how they maintain salt and water balance in their environment.