Physiology and Pathophysiology Basic Principles

Comprehensive vocabulary flashcards covering the basic principles of Physiology and Pathophysiology, including cellular structure, biomolecules, homeostatic mechanisms, and acid-base balance.

Physiology

The science that deals with the functioning of the organism, conceived as a result of the human desire to understand ourselves and the universe.

Pathophysiology

A branch of medicine that explains why and how diseases occur, their symptoms, and their 'history,' divided into initial, clinical, and resolution phases.

Level of Organization

The structural hierarchy of the human body consisting of the chemical level (atoms and molecules), cellular level, histic (tissue) level, organic level, systemic level, and organism level.

Cell

The basic structural, functional, and genetic unit of all living beings, capable of independent reproduction and nutrition.

Cell Classification

The four main types of cells: neurons, muscle cells, epithelial cells, and connective tissue cells.

Biomolecules

Molecules synthesized by living organisms containing carbon atoms; the four basic types are carbohydrates, lipids, proteins, and nucleotides.

Carbohydrates

Molecules composed of carbon, hydrogen, and oxygen in a $1:2:1$ ratio, with the general formula $(CH_2O)_n$ or $C_n(H_2O)_n$..

Monosaccharides

The simplest carbohydrates, including glucose, fructose, galactose, deoxyribose, and ribose.

Polysaccharides

Complex carbohydrates consisting of multiple sugar units, such as cellulose, starch, and glycogen.

Lipids

A diverse group of biomolecules containing primarily carbon and hydrogen atoms joined by nonpolar covalent bonds, often with an oily or greasy consistency.

Cholesterol

An essential lipid vital for cell membrane structure and the production of steroid hormones ($\text{cortisol}$, $\text{estrogens}$, $\text{testosterone}$), vitamin D, and bile acids.

HDL (High-Density Lipoprotein)

The 'good cholesterol' that helps eliminate excess cholesterol from arterial walls and transports it back to the liver.

LDL (Low-Density Lipoprotein)

The 'bad cholesterol' that transports cholesterol to the arteries; excess levels can penetrate the arterial wall.

Proteins

Polymers of amino acids that contain a central carbon, an amino group, a carboxyl group, a hydrogen, and a residual group ($R$).

Protein Structure levels

The four levels of organization: primary (straight cable), secondary (coiled), tertiary (loops), and quaternary (two cables coiled together).

Body Fluids

Aqueous liquids constituting more than $60 \text{\%}$ of body weight, essential for nutrient transport, waste elimination, and homeostasis.

Intracellular Fluid (ICF)

The fluid located inside the cells, comprising approximately $40 \text{\%}$ of total body weight.

Extracellular Fluid (ECF)

The fluid outside the cells, comprising approximately $20 \text{\%}$ of body weight, divided into plasma ($5 \text{\%}$) and interstitial fluid ($15 \text{\%}$).

Homeostasis

The self-regulation process by which living beings maintain a stable internal environment (temperature, pH, glucose, water) despite external changes.

Negative Feedback

The primary mechanism of homeostasis where the body detects deviations and activates mechanisms to restore balance, such as blood glucose control or pH levels.

Positive Feedback

A mechanism that reinforces a stimulus, such as breastfeeding, blood clotting, or uterine contractions during childbirth.

pH (Potential of Hydrogen)

A measure of acidity or alkalinity on a scale of $0$ to $14$, representing the concentration of hydrogen ions ($H^+$) where $7$ is neutral.

Acidosis

A physiological state where the blood pH falls below $7.35$, which can be metabolic or respiratory in origin.

Alkalosis

A physiological state where the blood pH rises above $7.45$, which can be metabolic or respiratory in origin.

Passive Transport

Transport of substances across the cell membrane following the electrochemical gradient with no energy expenditure, such as simple or facilitated diffusion.

Active Transport

Transport of substances against the electrochemical gradient requiring energy (ATP), including primary transport (e.g., $Na^+/K^+$ pump) and secondary transport (cotransport/countertransport).

Mitochondria

Energetic organelles surrounded by two membranes where cellular respiration occurs to produce ATP.

Ribosomes

Small organelles found free in the cytosol or attached to the RER that function to manufacture proteins.

Fluid Mosaic Model

The structural description of the plasma membrane, composed of a phospholipid bilayer with dispersed proteins, cholesterol, and carbohydrates.