p.2
Electrolytes and Fluid Compartments in the Body
What is the common unit for expressing blood glucose concentration in the United States?
Milligrams per deciliter (mg/dL).
p.10
Water as a Solvent and Its Biological Importance
How do water molecules interact with inorganic cations like Na+ and K+?
The oxygen atom of water interacts with them to form a hydration shell.
p.12
Water as a Solvent and Its Biological Importance
What are hydrogen bonds and their role in water?
Hydrogen bonds are strong enough to dissolve polar molecules in water and separate charges, yet weak enough to allow movement of water and solutes.
p.1
Chemical Foundations of Biochemistry
What are proteins made of?
Linear chains of amino acids that fold into complex three-dimensional structures.
p.3
Water as a Solvent and Its Biological Importance
Why is water important for molecule transport?
It is crucial for the transport of molecules and heat.
p.3
Water as a Solvent and Its Biological Importance
What role does water play in the body?
Acts as a solvent for substances like K+, glucose, ATP, and proteins.
p.3
Acids, Bases, and Buffers in Biological Systems
What do many compounds produced in the body release or accept?
Hydrogen ions, acting as acids or bases.
p.3
pH Regulation and Homeostasis
What is homeostasis?
The maintenance of a constant environment for cells.
p.2
Electrolytes and Fluid Compartments in the Body
What is the relationship between mM and mEq/L for ions?
1 mEq/L = mM × valence of ion.
p.7
Metabolic Diseases and Enzyme Dysfunction
What does Dianne's liver metabolize in ketoacidosis?
Fatty acids to ketone bodies such as acetoacetic acid and β-hydroxybutyric acid.
p.13
Electrolytes and Fluid Compartments in the Body
What role do semi-permeable cellular membranes play in fluid distribution?
They allow water to move freely while restricting other molecules.
p.10
Water as a Solvent and Its Biological Importance
What surrounds chloride and bicarbonate ions in solution?
A hydration shell of water molecules.
p.6
Water as a Solvent and Its Biological Importance
How does water contribute to heat dissipation in the body?
By absorbing and dissipating heat.
p.1
Role of Molecules in Cellular Function
What is the significance of protein structure in biochemistry?
It determines the protein's function and fate.
p.7
Electrolytes and Fluid Compartments in the Body
What is the total body water percentage in adults?
Roughly 50% to 60% of body weight.
p.1
Chemical Foundations of Biochemistry
What is the molar concentration of glucose in Dianne A.'s blood with a glucose level of 684 mg/dL?
3.8 mM (using the molecular weight of glucose).
p.13
Acids, Bases, and Buffers in Biological Systems
What does the dissociation constant for water (Kd) express?
The relationship between hydrogen ion concentration [H+], hydroxide ion concentration [OH-], and the concentration of water [H2O] at equilibrium.
p.9
Water as a Solvent and Its Biological Importance
How is the amount of oxygen quantified in a Clark electrode?
By measuring the current flow, which corresponds to the amount of oxygen that has reached the cathode.
p.14
Acids, Bases, and Buffers in Biological Systems
What characterizes acidic solutions?
They have a greater hydrogen ion concentration and a lower hydroxide ion concentration than pure water (pH < 7.0).
p.8
Water as a Solvent and Its Biological Importance
What property of water allows it to form hydrogen bonds?
The dipolar nature of the water (H2O) molecule.
p.5
Acids, Bases, and Buffers in Biological Systems
What determines the acidity of a solution?
The concentration of hydrogen ions (H+).
p.7
Electrolytes and Fluid Compartments in the Body
Why do obese people tend to have a lower percentage of body water?
Because fat has relatively little water associated with it.
p.13
Acids, Bases, and Buffers in Biological Systems
What is the ion product of water (Kw)?
The product of [H+] and [OH-], which is always constant.
p.13
Electrolytes and Fluid Compartments in the Body
What is osmolarity?
The total concentration of all dissolved molecules, including ions, organic metabolites, and proteins, usually expressed as milliosmoles (mOsm) per kg of water.
p.5
Water as a Solvent and Its Biological Importance
What is the role of water in the body?
Water is distributed between intracellular and extracellular compartments, including interstitial fluids, blood, and lymph.
p.8
Water as a Solvent and Its Biological Importance
What is the significance of water being dipolar?
It allows water to act as an effective solvent.
p.12
Electrolytes and Fluid Compartments in the Body
What are the major electrolytes in extracellular fluid (ECF)?
Na+ and Cl- are the major electrolytes in ECF.
p.5
Case Studies in Metabolic Disorders
What were the laboratory findings for Dianne A. upon admission?
Blood pH of 7.08, presence of ketone bodies in blood and urine, and blood glucose level of 648 mg/dL.
p.1
Chemical Foundations of Biochemistry
Why is understanding the roles and interactions of different chemicals important in medicine?
It enables our bodies to function properly.
p.1
Nomenclature and Properties of Compounds
What are some classes of compounds that are important in biochemistry?
Carbohydrates and enzymes.
p.7
Acids, Bases, and Buffers in Biological Systems
What do the ketone bodies dissociate to produce?
Anions (acetate and β-hydroxybutyrate) and hydrogen ions.
p.13
Electrolytes and Fluid Compartments in the Body
What is osmotic pressure?
The force required to keep the same amount of water on both sides of a membrane.
p.14
Acids, Bases, and Buffers in Biological Systems
What are examples of weak acids?
Organic acids containing carboxylic acid groups, such as acetic acid and β-hydroxybutyric acid.
p.5
Metabolic Diseases and Enzyme Dysfunction
What are metabolic acids generated from normal metabolism?
CO2, lactic acid, and ketone bodies.
p.9
Water as a Solvent and Its Biological Importance
What happens when oxygen reaches the cathode in a Clark electrode?
Electrons are attracted from the anode, reducing oxygen to water.
p.6
Water as a Solvent and Its Biological Importance
Why must most compounds in the body interact with an aqueous medium?
In order to function properly.
p.13
Electrolytes and Fluid Compartments in the Body
How does water distribute between different fluid compartments?
According to the concentration of solutes, or osmolarity, of each compartment.
p.5
pH Regulation and Homeostasis
What mechanisms does the body use to protect against acidity?
Buffers, expiration of CO2 through the lungs, and excretion of NH4+ and other ions through the kidneys.
p.14
Acids, Bases, and Buffers in Biological Systems
What are examples of strong acids?
Inorganic acids like sulfuric acid (H2SO4) and hydrochloric acid (HCl).
p.12
Electrolytes and Fluid Compartments in the Body
What is the osmolarity of isotonic saline solution?
Approximately 290 mOsm/kg H2O.
p.5
Acids, Bases, and Buffers in Biological Systems
What is a buffer?
A mixture of an undissociated acid and its conjugate base that resists changes in pH.
p.9
Water as a Solvent and Its Biological Importance
What is the basic mechanism used by blood-gas analyzers to measure pO2 and pCO2?
Through the use of specific gas-permeable membranes.
p.9
Water as a Solvent and Its Biological Importance
What occurs when CO2 crosses the membrane in a Severinghaus electrode?
CO2 interacts with bicarbonate, altering the equilibrium among CO2, carbonic acid, and bicarbonate.
p.10
Water as a Solvent and Its Biological Importance
Which atoms in organic molecules contribute to their solubility in water?
Electronegative atoms, generally oxygen or nitrogen.
p.6
Water as a Solvent and Its Biological Importance
What role does water play in biological systems?
It acts as a solvent, bathes cells, dissolves and transports compounds, and participates in chemical reactions.
p.1
Metabolic Diseases and Enzyme Dysfunction
What condition is characterized by high concentrations of carbohydrates in the blood?
Hyperglycemia, often seen in diabetes mellitus.
p.5
pH Regulation and Homeostasis
How much acid does the body produce from normal metabolism?
Approximately 13 to 22 mol/day.
p.14
Acids, Bases, and Buffers in Biological Systems
How are acids classified during metabolism?
As weak acids or strong acids based on their degree of dissociation.
p.14
Acids, Bases, and Buffers in Biological Systems
What is the significance of pKa?
It is the pH at which 50% dissociation of an acid occurs.
p.14
Acids, Bases, and Buffers in Biological Systems
What is the relationship between weak acids and their conjugate bases?
A weak acid (HA) dissociates into a hydrogen ion and an anionic component (A−), called the conjugate base.
p.12
Electrolytes and Fluid Compartments in the Body
What is the role of glucose in intravenous saline solutions?
Glucose provides fuel for the individual when added to saline solutions.
p.3
pH Regulation and Homeostasis
What can significant deviations from a constant environment lead to?
Conditions like acidosis or dehydration, which may be life-threatening.
p.3
Water as a Solvent and Its Biological Importance
What does this chapter describe regarding water?
The role of water in the body and the buffer systems used to protect against acids and bases.
p.1
Metabolic Diseases and Enzyme Dysfunction
What is the role of enzymes in metabolic diseases?
They can malfunction, leading to various metabolic disorders.
p.14
Acids, Bases, and Buffers in Biological Systems
What characterizes basic solutions?
They have a lower hydrogen ion concentration and a greater hydroxide ion concentration (pH > 7.0).
p.8
Water as a Solvent and Its Biological Importance
What gives the oxygen atom in water a partial negative charge?
The attraction of shared electrons towards the oxygen atom in the covalent bond.
p.5
Acids, Bases, and Buffers in Biological Systems
What is the Henderson-Hasselbalch equation used for?
To relate the pH of a solution, the Ka of an acid, and the extent of its dissociation.
p.7
Electrolytes and Fluid Compartments in the Body
How does age affect body water percentage?
Older people have a lower percentage of body water than younger people.
p.9
Water as a Solvent and Its Biological Importance
What electrode is used to determine pCO2?
A Severinghaus electrode.
p.10
Water as a Solvent and Its Biological Importance
Why can polar organic molecules and inorganic salts dissolve readily in water?
Because water forms hydrogen bonds and electrostatic interactions with these molecules.
p.8
Electrolytes and Fluid Compartments in the Body
What does extracellular water include?
Fluid in plasma and interstitial water.
p.1
Cellular Communication and Signaling
What is the relationship between cellular function and communication?
Cells communicate through chemical messengers to carry signals.
p.13
Acids, Bases, and Buffers in Biological Systems
What are acids and bases in terms of hydrogen ions?
Acids donate hydrogen ions (H+) to a solution, while bases accept hydrogen ions.
p.12
Electrolytes and Fluid Compartments in the Body
Why is saline used instead of water for rehydration?
Saline maintains osmolarity similar to plasma, preventing large shifts of water or swelling.
p.12
Water as a Solvent and Its Biological Importance
What happens to hydrogen bonding in water when heat is added?
Hydrogen bonding decreases, allowing water to absorb heat without significant temperature change.
p.9
Water as a Solvent and Its Biological Importance
How does the change in pH relate to the measurement of pCO2?
The change in pH is directly proportional to the amount of CO2 gas that has entered the electrode.
p.6
Metabolic Diseases and Enzyme Dysfunction
What did Percy V. discover Dennis V. doing?
Dennis V. had a mouthful of aspirin.
p.1
Metabolic Diseases and Enzyme Dysfunction
How do pharmacologic drugs treat metabolic diseases?
By correcting the malfunction of enzymes and proteins.
p.7
pH Regulation and Homeostasis
What effect does the dissociation of ketone bodies have on blood pH?
It lowers blood and cellular pH below the normal range.
p.12
Water as a Solvent and Its Biological Importance
What allows water to resist temperature changes?
The structure of water, including its high heat of fusion and thermal conductivity.
p.7
Electrolytes and Fluid Compartments in the Body
How does body water percentage differ between genders?
Women tend to have a lower percentage of body water than men.
p.9
Water as a Solvent and Its Biological Importance
What advancements have improved the portability of blood-gas analyzers?
Improved manufacturing techniques allowing the use of microelectrodes and tiny circuit boards.
p.7
Metabolic Diseases and Enzyme Dysfunction
What happens when the amount of insulin Dianne injects is inadequate?
She remains in a condition similar to a fasting state despite ingesting food.
p.8
Electrolytes and Fluid Compartments in the Body
What is transcellular water?
A small, specialized portion of extracellular water including gastrointestinal secretions, urine, sweat, and fluid that has leaked through capillary walls.
p.12
Water as a Solvent and Its Biological Importance
What is the significance of hydration shells?
Hydration shells surround anions and cations, facilitating their movement through water.
p.9
Water as a Solvent and Its Biological Importance
How does oxygen diffuse in a Clark electrode?
Oxygen diffuses through a membrane specific for oxygen permeability and reaches the cathode.
p.13
Electrolytes and Fluid Compartments in the Body
What happens when the osmolarity of blood and interstitial fluid is too high?
Water moves out of the cells.
p.5
Case Studies in Metabolic Disorders
What condition did Dianne A. experience that led to her hospitalization?
She was in a coma due to severe insulin deficiency and high blood glucose levels.
p.9
Water as a Solvent and Its Biological Importance
What is a hydrogen bond?
A weak non-covalent interaction between the hydrogen of one molecule and an electronegative atom of another.
p.8
Water as a Solvent and Its Biological Importance
What happens to the electron density in water molecules?
The electron cloud lies above and below the plane formed by the water molecule.
p.13
Acids, Bases, and Buffers in Biological Systems
What is the pH of pure water?
7, which indicates it is neutral.
p.5
pH Regulation and Homeostasis
What is the significance of bicarbonate in the body?
It acts as a buffer to maintain pH in body fluids.
