44_Lecture_Presentation 2023

Page 1: Vasey’s Trillium

• Habitat: Open sunny area

• Description: Features characteristic deep pink/red flower with three petals and distinctive leaves.

Page 2: Painted Trillium

• Location: Porter’s Creek Trail

• Date: 4/13/12

• Habitat: Mid-level Woodland

• Description: Contains 3 large white petals with a ring of color radiating from the center.

Page 3: Little Sweet Betsy

Page 4: Chapter 44

• Source: Pearson Education, Inc (2017)

Page 5: A Balancing Act

• Physiological Systems: Operate in a fluid environment.

• Water and Solutes: Must maintain relative concentrations within narrow limits.

• Osmoregulation: Controls concentrations of solutes and balances water gain/loss.

Page 6: Osmoregulation in Different Environments

• Desert and Marine Animals: Face desiccating environments leading to rapid water depletion.

• Freshwater Animals: Conserve solutes and absorb salts from environment.

• Excretion: Removal of nitrogenous metabolites and other waste products.

Page 7: Concept 44.1: Osmoregulation Overview

• Osmoregulation Process: Balancing the uptake and loss of water and solutes.

• Driving Force: Movement of water and solutes driven by concentration gradients across plasma membrane.

Page 8: Osmosis and Osmolarity

• Osmosis: Water enters/leaves cells by osmosis.

• Osmolarity: Solute concentration determines water movement across selectively permeable membranes.

  • If isoosmotic, water crosses membrane at equal rates in both directions.

Page 9: Movement of Water in Solutions

• Difference in Osmolarity: Water flows from hypoosmotic to hyperosmotic solutions.

  • Definitions:

    • Hypo-: Below concentration.

    • Hyper-: Above concentration.

Page 10: Selectively Permeable Membranes

• Water Movement:

  • Hyperosmotic Side: Higher solute concentration & lower free water concentration.

  • Hypoosmotic Side: Lower solute concentration & higher free water concentration.

Page 11: Osmoregulatory Challenges and Mechanisms

• Water Balance Methods:

  • Osmoconformers: Isoosmotic with surroundings; do not regulate osmolarity.

  • Osmoregulators: Expend energy to manage water uptake/loss.

Page 12: Animal Variations

• Stenohaline Animals: Cannot tolerate significant external osmolarity changes.

• Euryhaline Animals: Can survive significant variations in osmolarity.

Page 13: Marine Animals

• Invertebrates: Most are osmoconformers (isosmotic).

• Vertebrates: Many are osmoregulators; marine bony fishes are hypoosmotic to seawater.

• Water Management: Drink seawater and eliminate excess salts through gills and kidneys.

Page 14: Osmoregulation in Sharks

• Nitrogenous Waste: Coupled with osmoregulation through urea elimination.

• Urea Concentration: High in sharks, balanced with TMAO to prevent toxicity.

• Water Intake: Gained via food and absorption; excess water is excreted in urine.

Page 15: Osmoregulation in Marine Fish

• Water/Gain: Through food and seawater.

• Osmotic Water Loss: Through gills and body surface.

• Salt Excretion: Through gills with minimal urine loss.

Page 16: Osmoregulation in Freshwater Animals

• Water Intake: Constantly absorbed from a hypoosmotic environment.

• Salt Loss: Occurs through diffusion, managed by drinking minimal water and excreting dilute urine.

• Salt Replenishment: Through diet and gill absorption.

Page 17: Osmoregulation in Freshwater Fish

• Water/Salt Management: Gains water through gills and food; excretes large volumes of dilute urine.

Page 18: Animals in Temporary Waters

• Adaptation: Some aquatic invertebrates enter anhydrobiosis, losing almost all body water during dormancy.

  • Example: Tardigrades can reduce water content dramatically.

Page 19: Water and Salt Gains and Losses in Land Animals

• Gains Water:

• Loses Water:

• Gains Salt:

• Loses Salt:

Page 20: Water and Salt Regulation in Land Animals

• Prevent Water Loss: Strategies to minimize dehydration.

• Prevent Salt Loss: Adaptations to maintain salt levels.

Page 21: Adaptations for Terrestrial Survival

• Body Coverings: Protect against dehydration.

• Behavioral Adaptations: Nocturnal lifestyles, drinking moist food, and metabolic water production are crucial.

Page 22: Energetics of Osmoregulation

• Energy Expenditure: Varies based on osmolarity differences and transportation difficulty.

Page 23: Transport Epithelia in Osmoregulation

• Function: Specialized epithelial cells facilitate controlled solute movement.

• Location: Arranged in tubular networks, such as in nasal glands of marine birds functioning to remove excess salts.

Page 24: Transport Epithelia Illustration

• Figure: Nasal salt gland and its function.

Page 25: Detailed Illustration of Transport Epithelia

• Structure: Involves secretory cells, blood flow components, and how salt is secreted.

Page 26: Nitrogenous Waste and Water Balance

• Impact of Waste Products: Affect overall water balance; includes nitrogenous breakdown products.

Page 27: Forms of Nitrogenous Waste

• Types: Ammonia, urea, uric acid.

• Toxicity and Energy Costs: Varied based on the type produced and habitat relevance.

Page 28: Ammonia as Waste

• Water Requirement: Needed in large quantities for excretion; toxic but requires low energy to produce.

Page 29: Ammonia Excretion in Aquatic Animals

• Common in: Most aquatic animals excrete ammonia with a high water requirement due to toxicity.

Page 30: Urea as Waste

• Excretion in Terrestrial Animals: Many mammals excrete urea, which is less toxic than ammonia and requires moderate water for elimination.

• Production Cost: Energetically more expensive than ammonia.

Page 31: Urea Characteristics

• Excretion in: Mammals, amphibians, and some marine species.

Page 32: Uric Acid as Waste

• Excretion in: Insects, snails, many reptiles (birds).

• Property: Uric acid is less toxic, excreted with minimal water.

Page 33: Uric Acid Production

• Energy and Water Characteristics: More energy-intensive to create but requires little water for excretion.

Page 34: Uric Acid and Gout

• Relation to Humans: Uric acid can be a byproduct of metabolism involved in conditions like gout.

Page 35: Summary of Nitrogenous Waste Types

• Chart: Displays nitrogenous wastes produced by various animal groups (aquatic, terrestrial).

Page 36: Excretory Processes

• Filtration Functions:

  • Filtration: Body fluid filtering

  • Reabsorption: Recovery of valuable solutes

  • Secretion: Addition of nonessential solutes & wastes

  • Excretion: Releasing processed wastes.

Page 37: Illustration of Excretory Processes

• Diagram: Breakdown of filtration, reabsorption, secretion, and excretion.

Page 38: Survey of Excretory Systems

• Overview: Excretory systems vary among animals, involving complex tubule networks.

Page 39: Protonephridia System

• Structure: Network of dead-end tubules capped by flame bulbs; excrete dilute fluids and support osmoregulation.

Page 40: Diagram of Protonephridia

• Function Illustrated: Explains the components and operations of protonephridia systems.

Page 41: Metanephridia

• Structure in Earthworms: Comprised of tubules for collecting coelomic fluid to create dilute urine for excretion.

Page 42: Components of Metanephridia

• Illustration: Components involved in metanephridia, showcasing fluid collection and urine production.

Page 43: Malpighian Tubules

• Function in Insects: Remove nitrogenous wastes from hemolymph and aid in osmoregulation; produce dry waste (mainly uric acid).

Page 44: Malpighian Tubules and Waste Removal

• Diagram Explained: Shows the anatomy and waste management of Malpighian tubules.

Page 45: Kidneys and Excretion

• Function in Vertebrates: Involved in both excretion and osmoregulation with complex tubule organization.

Page 46: Excretory Organ Structure

• Illustration: Overview of kidney anatomy, including key components supporting excretion.

Page 47: Kidney Structure Details

• Components: Renal cortex, medulla, arteries, and veins described with their roles.

Page 48: Nephron Types

• Categories: Cortical and juxtamedullary nephrons differing in function and structure.

Page 49: Nephron Organization

• Components Included: Afferent arteriole, Bowman's capsule, proximal and distal tubules outlined.

Page 50: Glomerular Components

• Filtration Structures: Detailed structures within the renal corpuscle contributing to filtration.

Page 51: Kidney Blood Vessels

• Blood Flow Overview: Illustrates the blood vessels associated with the kidney's filtration system.

Page 52: Nephron Animation

• Visual Aid: Representation of nephron function and organization in kidneys.

Page 53: Nephron Filtrate Composition

• Content in Filtrate: Salts, glucose, amino acids, vitamins, and nitrogenous wastes outlined.

Page 54: Animation of Bowman’s Capsule Function

• Educational Tool: Demonstrates processes occurring in Bowman’s capsule and proximal tubule.

Page 55: Reorganization of Nephron Components

• Functional Details: Outlines flow of filtrate through nephron structures.

Page 56: Proximal Tubule Function

• Reabsorption Process: Active and passive movement of ions and nutrients from filtrate to capillaries.

Page 57: Nephron Organization Overview

• Components Recap: Repeated exploration of nephron structures pertaining to excretory functions.

Page 58: Proximal and Distal Tubule Reabsorption

• Filtrate Composition Changes: Detailed changes occurring in filtrate composition in nephron.

Page 59: Distal Tubule Function

• Regulatory Role: Regulation of K+ and NaCl concentrations, contributing to pH balance.

Page 60: Descending Limb of Loop of Henle

• Water Reabsorption Process: Driven by osmotic gradients creating concentrated filtrate.

Page 61: Nephron Structure Review

• Circulation of Filtrate: Annotated flow-through nephron structures.

Page 62: Filtrate Composition in the Nephron

• Illustrates Filtration and Transport Processes: Highlights active and passive processes influencing osmolarity changes.

Page 63: Ascending Limb of Loop of Henle

• Salt Diffusion: Diffusion of salt without water; leads to dilute filtrate.

Page 64: Loop of Henle Explanation

• Educational Animation: Teaches fluid movement and concentration mechanisms in nephron.

Page 65: Nephron Structure Summary

• Visual Representation: Conveys nephron organization supporting excretory processes.

Page 66: Nephron Filtration Dynamics

• Components Overview: Annotation of nephron sections involved in filtration.

Page 67: Distal Tubule Roles

• Ion Concentration Regulation: Regulation of body fluid concentrations and pH.

Page 68: Collecting Duct Animation

• Visual Learning Tool: Explains collecting duct processes in urine formation.

Page 69: Nephron Organization Recap

• Summary of Nephron Components: Consolidates knowledge on nephron and urine processing.

Page 70: Nephron Structure

• Clear Visualization: Structured overview of nephron organization.

Page 71: Collecting Duct Functionality

• Urine Formation: Focus on solute and water reabsorption processes occurring in the duct.

Page 72: Solute Gradients in Kidney Function

• Water Conservation Mechanism: Energy expenditure facilitates hyperosmotic urine formation.

Page 73: Urine Concentration Process

• Volume Decrease: Filtrate volume reduction through water and salt reabsorption effects.

Page 74: Countercurrent Multiplier Function

• Active Transport of NaCl: Maintains osmotic gradients for efficient kidney function.

Page 75: Collecting Duct and Osmolarity

• Water Extraction Process: Urine produced through osmosis relative to interstitial fluid osmolarity.

Page 76: Diagram of Osmolarity in Kidney Layers

• Osmolarity Levels: Changes in osmolarity values throughout kidney regions.

Page 77: Second Osmolarity Diagram

• Comparative Visuals: Illustrates osmolarity variation across kidney structures.

Page 78: Third Osmolarity Diagram

• Complex Osmolarity Changes: Graphical representation of solute movement and concentration levels.

Page 79: Adaptations of Vertebrate Kidneys

• Variation in Nephrons: Structural differences tailored for various habitats.

Page 80: Mammalian Nephron Adaptations

• Juxtamedullary Nephrons: Enhanced water conservation in terrestrial environments.

Page 81: Case Study - Vampire Bat

• Kidney Function Significance: Ability to quickly adjust urine concentration in blood-feeding mammals.

Page 82: Birds and Reptiles Adaptations

• Water Conservation: Short loops of Henle and uric acid excretion for effective water management.

Page 83: Adaptations in Freshwater Fishes and Amphibians

• Water Management Strategies: Emphasis on salt conservation and water reabsorption techniques.

Page 84: Marine Bony Fishes Kidney Function

• Adaptations for Thriving in Saline Environments: Reduced nephron count and filtration rates for water management.

Page 85: Osmoregulation in Marine Fishes

• Ion Transport Mechanisms: Importance of chloride cells for controlling salt excretion in gills.

Page 86: Hormonal Control in Kidneys

• Response Mechanism: Urine volume and osmolarity adjustments to salt and water availability.

Page 87: Homeostasis Regulation

• Nervous and Hormonal Interplay: Coordination of kidney functions for consistent blood pressure and volume.

Page 88: Antidiuretic Hormone (ADH) Function

• Mechanism of Action: ADH increases water reabsorption via aquaporin channels in collecting ducts.

Page 89: Neuroanatomy in ADH Regulation

• Hormonal Release Pathway: Illustrative diagram of neurosecretory pathways influencing ADH secretion.

Page 90: ADH Functionality in Cells

• Mechanism of Action: Binding of ADH leading to formation and insertion of aquaporin channels.

Page 91: Osmoreceptor Functionality

• Regulatory Feedback: Monitoring blood osmolarity to control ADH release effectively.

Page 92: Blood Osmolarity Changes

• Normal vs. Elevated Levels: Discusses physiological responses to osmolarity changes, particularly during dehydration.

Page 93: Osmoreceptor Triggering Mechanism

• ADH Response Activation: Cascading effect leading to increased kidney water reabsorption during hyperosmolarity.

Page 94: Hydration during Increased Osmolarity

• Thirst Mechanism Activation: Links between osmoreceptors, thirst generation, and ADH influences.

Page 95: Animation on ADH Effect

• Educational Content: Visual presentation of ADH effects on kidney function.

Page 96: Alcohol's Impact on ADH

• Diuretic Effect: Inhibits ADH release leading to increased water loss and potential dehydration.

Page 97: Renin-Angiotensin-Aldosterone System (RAAS) Overview

• Feedback Mechanism Functioning: Describes the renin release triggered by blood pressure drops at glomeruli.

Page 98: Angiotensin II Role

• Physiological Impact: Raises blood pressure and stimulates aldosterone secretion to enhance blood volume.

Page 99: Blood Pressure and Volume Changes

• Physiological Impact Diagram: Steps that occur in response to drops in blood pressure or blood volume.

Page 100: Sensors in Blood Pressure Regulation

• Process Initiation: Juxtaglomerular apparatus (JGA) sensing blood pressure changes and initiating RAAS.

Page 101: Juxtaglomerular Operations

• Renin Release: Promotes the renal and systemic physiological adjustments following blood pressure drops.

Page 102: Sodium and Water Reabsorption Processes

• Effect of Aldosterone: Direct increase in sodium and water reabsorption, supporting blood pressure regulation.

Page 103: Homeostatic Regulation Overview

• Combined Actions of Hormones: Outlines how ADH and RAAS work together to manage fluid homeostasis in response to variable conditions.

Osmoregulation Overview

Osmoregulation is the physiological process that maintains the balance of water and solutes in an organism, crucial for maintaining homeostasis in varying environments. This process involves complex mechanisms that enable organisms to either regulate their internal osmolarity in relation to their external environment or conform to it.

Key Concepts

• Driving Force: The movement of water and solutes is primarily driven by concentration gradients across plasma membranes, determining how substances are exchanged between the intracellular and extracellular environments.

• Osmosis: Water moves in and out of cells via osmosis, a passive process influenced by the osmolarity, or concentration of solutes, in the surrounding fluid. Depending on the osmotic environment, cells can either swell (in hypotonic solutions) or shrink (in hypertonic solutions).

Mechanisms of Osmoregulation

1. Osmoconformers

• These organisms maintain isoosmotic conditions with their environment, whereby their internal osmolarity matches that of their surrounding aquatic environment. This strategy is common in many marine invertebrates.

2. Osmoregulators

• These organisms expend energy to control their internal osmotic conditions. They adjust their water and solute concentrations actively. Examples include:

  • Freshwater Animals: They tend to gain excess water from their hypoosmotic environment and thus need to excrete large volumes of dilute urine to maintain osmotic balance while absorbing salts actively, often through specialized gill cells.

  • Marine Animals: Many marine bony fishes are hypoosmotic to seawater. To manage the high salinity, they drink seawater and actively excrete the excess salts through their gills and kidneys, producing a small amount of concentrated urine.

Adaptations in Different Environments

• Desert and Marine Animals: Face extreme environments that lead to rapid water depletion. Adaptations often include water-storing capabilities and efficient excretory processes to minimize water loss.

• Freshwater Animals: Employ strategies for conserving solutes; they absorb salts from their hypoosmotic surroundings and excrete large quantities of dilute urine to counteract the osmotic influx of water.

Importance of Osmoregulation

Osmoregulation is vital for the survival and wellbeing of animals by affecting metabolic processes, behavioral adaptations, and overall ecological fitness. It plays a significant role in nutrient absorption, waste elimination, and maintaining stable conditions for cellular functions across diverse habitats. Understanding these mechanisms provides insights into how organisms adapt to their environments and the evolutionary paths they have taken in response to challenges posed by varying osmotic pressures.

Osmoregulation is the physiological process that maintains the balance of water and solutes in an organism, crucial for maintaining homeostasis in varying environments. This process involves complex mechanisms that enable organisms to either regulate their internal osmolarity in relation to their external environment or conform to it.

Key Concepts

• Driving Force: The movement of water and solutes is primarily driven by concentration gradients across plasma membranes, determining how substances are exchanged between the intracellular and extracellular environments.

• Osmosis: Water moves in and out of cells via osmosis, a passive process influenced by the osmolarity, or concentration of solutes, in the surrounding fluid. Depending on the osmotic environment, cells can either swell (in hypotonic solutions) or shrink (in hypertonic solutions).

Mechanisms of Osmoregulation

1. Osmoconformers

• These organisms maintain isoosmotic conditions with their environment, whereby their internal osmolarity matches that of their surrounding aquatic environment. This strategy is common in many marine invertebrates.

2. Osmoregulators

• These organisms expend energy to control their internal osmotic conditions. They adjust their water and solute concentrations actively. Examples include:

  • Freshwater Animals: They tend to gain excess water from their hypoosmotic environment and thus need to excrete large volumes of dilute urine to maintain osmotic balance while absorbing salts actively, often through specialized gill cells.

  • Marine Animals: Many marine bony fishes are hypoosmotic to seawater. To manage the high salinity, they drink seawater and actively excrete the excess salts through their gills and kidneys, producing a small amount of concentrated urine.

Adaptations in Different Environments

• Desert and Marine Animals: Face extreme environments that lead to rapid water depletion. Adaptations often include water-storing capabilities and efficient excretory processes to minimize water loss.

• Freshwater Animals: Employ strategies for conserving solutes; they absorb salts from their hypoosmotic surroundings and excrete large quantities of dilute urine to counteract the osmotic influx of water.

Importance of Osmoregulation

Osmoregulation is vital for the survival and wellbeing of animals by affecting metabolic processes, behavioral adaptations, and overall ecological fitness. It plays a significant role in nutrient absorption, waste elimination, and maintaining stable conditions for cellular functions across diverse habitats. Understanding these mechanisms provides insights into how organisms adapt to their environments and the evolutionary paths they have taken in response to challenges posed by varying osmotic pressures.