Human Physiology: Body Temperature Quiz

Body Fluids

• Body fluid comprises 60% of an adult human body, predominantly a water solution of ions and other substances.
• Total body water (TBW) amounts to 42 liters in a 70 kg adult male.
• Physiological factors impacting TBW include body fat content (obese individuals have lower TBW), sex (females generally have less TBW than males) and age (young people usually have higher TBW compared to older ones).

Physiological level of TBW

• A table depicting TBW percentage of body weight across different developmental stages (fetus, infant, male, and female).

Distribution of TBW in a healthy adult 70 kg male

• A diagram depicting the distribution of total body water (TBW) in a 70 kg male, illustrating the intracellular fluid (ICF) and extracellular fluid (ECF) components, including plasma and interstitial fluid.

Human circulatory system

• A diagram illustrating the human circulatory system and pulmonary and systemic circuits.

Distribution of TBW in a healthy adult 70 kg male

• A table delineating the fluid compartments in a healthy 70 kg adult male, encompassing percentage of body weight, fraction from total body water (TBW), and respective fluid volumes in liters. The table also includes important notes regarding each compartment.

Transcellular fluid as a minor ECF Compartment

• A series of images illustrating various forms of transcellular fluids.

Transcellular fluids as a minor ECF Compartment

• A summary describing transcellular fluids as minor components of extracellular fluid (ECF). It highlights that these fluids occupy specific cavities in the body, performing specialized functions.

Exchange between compartments

• A diagram illustrating the dynamic exchange of fluid between intracellular fluid (ICF) and interstitial fluid (ISF) via plasma membranes, and between plasma and ISF through capillary walls.

Ionic composition of different fluids

• The composition of intracellular and extracellular fluids differ significantly in their specific ion concentrations. Plasma and interstitial fluids are relatively similar in composition but differ in the presence of plasma proteins.

Ionic composition of different compartments

• Comparison of ionic compositions in intracellular fluid (ICF) and extracellular fluid (ECF). ICF has high K+ and low Na+, the opposite is true of ECF. Protein concentration differences also exist.

Student Activity (True or False)

• A series of true/false statements regarding body fluid concepts and the properties of ICF and ECF

Movement of water between different compartments

• Description of hydrostatic pressure, a force exerted by fluid within a closed compartment and influences water movement.
• Description of osmosis, the movement of water across a semipermeable membrane from an area of high water concentration to one of low water concentration.

Movement of water between different compartments

• Diagram explaining the hydrostatic and oncotic forces acting on the flow of water through capillaries.

Movement of water between different compartments

• A diagram and description of osmosis, clarifying the solvent movement based on solute concentration differences.

Osmosis

• Water’s movement across a semipermeable membrane is described.
• Osmosis is explained as the net diffusion of water across the membrane from a region of high water concentration (low solute concentration) to a region of low water concentration (high solute concentration).

Osmosis

• Definition and description of osmotic pressure and how it relates to the concentration of solutes.

Osmosis

• Definition of osmolarity as the measure of solute concentration in a solution. Solutes that break down into ions are more osmotically active than non-ionizing solutes.

Osmosis

• Definition and description of osmolarity, comparing its significance to non-ionizing solutes and how it is influenced by solute dissociation into ions.

Osmosis

• Definition of osmolarity and the relationship between osmotic pressure and osmolarity at a specific temperature.

Osmosis

• Calculation formula for determining plasma osmolarity.
• Description of how various substances—blood urea nitrogen (BUN), glucose levels, and renal function—impact plasma osmolarity.

Tonicity

• Explanation of the concept of tonicity, classifying solutions relative to plasma into isotonic, hypertonic, and hypotonic categories.

Tonicity

• Diagram comparing effects of isotonic, hypertonic, and hypotonic solutions on red blood cells; including descriptions of cell shrinkage, swelling/rupture.
• Explanation of normal osmolality of extracellular and intracellular fluids.

Gibbs-Donnan Effect

• Description of the Gibbs-Donnan effect, stating that the presence of an impermeable ion on one side of a membrane predictably affects the distribution of other diffusible ions.
• Elaboration on how the effect influences the distribution of ions in the body, including discussions of equilibrium and electrical differences between intracellular and extracellular fluids.

Filtration

• Definition of filtration in terms of water and solute movement across a porous membrane from high to low pressure.
• Explanation of filtering forces and reabsorbing forces and how they relate to fluid exchange across capillaries.
• Description of factors affecting the rate of filtration, including pressure gradients, surface area and permeability of membranes.

Ultrafiltration

• Definition of ultrafiltration as a specialized type of filtration at glomeruli of kidneys.

Movement of water across membranes

• Explanation of how water moves within the body by describing osmosis through phospholipid bilayer and the presence of water channels called aquaporins.

Student Activity (True or False)

• A set of true/or false questions related to osmosis, vesicular (active) transport, and filtration.

Action Potential

• Discussion of resting membrane potential, emphasizing its negative value and how it is established in excitable tissues.

Action Potential

• Discussion of the ionic basis of action potential, specifically highlighting the role of Na+ and K+ channels in creating the membrane potential changes.

Action Potential

• Explanation of phases of action potential, including the latent period, depolarization, repolarization, and afterhyperpolarization.
• Explaining roles of voltage-gated sodium and potassium channels in the process.

Action potential of a neuron

• Description of the mechanism that initiates action potentials.
• Explaining the ionic basis involved in action potential initiation and propagation.

Action Potential, Excitability, and Refractory Periods

• Description of the phases of excitability including absolute refractory and relative refractory phases, highlighting their importance.

Propagation of Nerve Impulse (Conduction of Action Potential)

• Description of how action potentials propagate in unmyelinated and myelinated nerves (saltatory conduction).

Action potential of a neuron

• Characteristics of action potentials, including all or none law, constant amplitude, and propagation along nerves.

Local potential

• Explanation of how threshold stimuli produce action potentials, whereas subthreshold stimuli elicit graded potentials (also known as local potentials or electrotonic potentials) that do not propagate.

Local potential

• Comparison of local potentials and action potentials, distinguishing between their amplitude, propagation, and summability characteristics.

Receptors overview

• Discussion of intracellular and extracellular receptors, and their varying significance in diverse body systems.

Signal Transduction

• Overall description of the signalling process by which a chemical messenger activates a series of intracellular steps resulting in a cellular response.

Signal transduction

• Description of how lipid-soluble chemical messengers act on cytoplasmic receptors (intracellular receptors), influencing gene activity.

Signal transduction

• Description of how water-soluble chemical messengers signal through surface receptors, triggering various intracellular responses.
• Overview of three types of signal receptors: ligand-gated receptor-channels, receptor-enzyme complexes, and G-protein-coupled receptors; also defining these as types of receptors that initiate signal transduction.

Signal transduction

• Explaining and describing the activation of cAMP second-messenger pathway, along with discussing the consequences this may produce within a cell.

Signal transduction

• Description and discussion on how the signal cascades, intracellular mediators and receptors combine to affect cellular responses.

• Discuss the mechanisms of shutting down the responses of signal transduction pathways, noting the reversing effects of protein kinases using protein phosphatases on the specific protein.

• Receptors overview of different types of receptors, and their roles in various body functions.

Signal transduction

• A summary and description of how receptor number adjusts in response to various stimulatory factors.

Clinical Note

• Illustrative examples of receptor participation in physiological conditions and how drugs target receptors to treat disorders, such as asthma and stomach acid abnormalities.

Clinical Note: Receptor Diseases

• Description of how certain diseases arise from the presence of antibodies that target specific receptors in body tissues and the consequential effects.

Student Activity (True or False)

• A concise set of true/false statements related to receptor activity and function.

Test your knowledge on the physiological aspects of body temperature in this quiz. Explore what increased body temperature indicates, its associated conditions, potential symptoms, and common physiological responses. Perfect for students of human biology and health sciences.