Podcast Beta
Questions and Answers
Why does ice float on liquid water?
What property of water allows it to have a stable environment for organisms?
What role does high latent heat play in water's behavior?
What does cohesion in water refer to?
Signup and view all the answers
What effect does high surface tension have on water?
Signup and view all the answers
Study Notes
Water Properties
- Incompressibility: This ensures that water can be used for support, like the turgor pressure in plants.
- Density: Water is most dense at 4°C. Ice (solid water) floats on liquid water due to a 9% decrease in density upon freezing, which insulates ponds and provides habitat for penguins.
- High Latent Heat: Water requires a lot of energy to change its state, making it a stable environment for organisms due to less evaporation and freezing.
- High Specific Heat Capacity: Water requires a lot of energy to change its temperature, making it a stable environment. This also helps in maintaining stable body temperature.
- High Surface Tension: Water's surface tension is due to cohesion (attraction between water molecules) and adhesion (attraction between water and other surfaces). This tension is responsible for things like water droplets formation.
- Amphoteric: Water can act as both an acid and a base, donating or accepting protons.
pH
- Acids: Release H+ ions in solution. Strong acids ionize completely, while weak acids only partially ionize.
- Bases (Alkalines): Release OH- ions in solution or accept protons. Strong bases ionize completely, while weak bases only partially ionize.
- Amphoteric Substances: Act as both acids and bases, like water and amino acids.
pH Importance
- Blood pH: 7.1 - 7.4 (any changes can be fatal)
- Urine pH: 6.8 (slightly acidic) Changes in pH can lead to the precipitation of salts and the formation of urinary stones.
- Gastric Juice pH: 1.5 - 2 (highly acidic) Increased acidity can lead to peptic ulcers, and decreased acidity can lead to hypoacidity.
- General: All reactions in living protoplasm occur in buffered media. Any pH abnormality can lead to illness and potentially fatal conditions.
Physiological Buffers
- Bicarbonate Buffer (H2CO3, NaHCO3): Most important buffer in the blood. It helps regulate pH by releasing or absorbing H+ ions.
- Phosphate Buffer (NaH2PO4, Na2HPO4): Main buffer of the urinary system.
- Hemoglobin Buffer: This buffer controls sudden additions of acid or base.
- Proteins and Amino Acids: Act as important buffers in blood and tissues.
Acid-Base Balance
- Body uses three mechanisms:
- Buffering agents
- Respiratory system
- Renal system
- Acidosis: Arterial pH below 7.35.
- Alkalosis: Arterial pH above 7.45
Types of Acidosis/Alkalosis
- Primary Respiratory Disturbances: Occur due to changes in CO2 levels.
- Primary Metabolic Disturbances: Occur due to changes in bicarbonate levels.
Acidosis
- Primary Respiratory Acidosis: Occurs when PCO2 is above 45 mmHg. Causes include acute and chronic pulmonary insufficiency.
- Primary Metabolic Acidosis: Occurs when bicarbonate levels are below 22 mEq/liter. Causes include diarrhea, carbonic anhydrase inhibitors, lactic acidosis, keto-acidosis, and aspirin poisoning.
Alkalosis
- Primary Respiratory Alkalosis: Occurs when PCO2 is below 35 mmHg. Causes include hyperventilation, fever, and high altitudes.
- ** Primary Metabolic Alkalosis:** Occurs when bicarbonate levels are above 29 mEq/liter. Causes include loss of gastric HCl, administration of diuretics.
Acidosis and Alkalosis Compensation
- Body compensates for acid-base imbalances by:
- Respiratory system: Adjusting CO2 levels.
- Renal system: Regulating bicarbonate levels.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.