Anatomy & Physiology: Introduction and Chemical Level of Organization

Vocabulary practice flashcards covering introductory anatomical terminology, body planes, homeostatic feedback loops, chemical bonding, and biomolecular structures from Chapter 1 and Chapter 2.

Gross Anatomy

The branch of anatomy that examines large structures that can be dissected for physical examination.

Cytology

The microscopic study of body cells and their internal structures.

Histology

The microscopic study of tissues.

Pathophysiology

A subdiscipline of physiology focusing on the function of a body system during disease or injury.

Anatomic Position

The standard reference position characterized by an upright stance, feet parallel and flat on the floor, upper limbs at the sides, palms facing anteriorly, head level, and eyes looking forward.

Coronal Plane

A vertical plane that divides the body or an organ into anterior (front) and posterior (back) parts.

Transverse Plane

A horizontal plane that divides the body or an organ into superior (top) and inferior (bottom) parts.

Midsagittal Plane

A vertical plane that divides the body or an organ into equal left and right halves.

Homeostasis

The ability of an organism to maintain a consistent internal environment in response to changing internal or external conditions.

Autoregulation

A homeostatic mechanism occurring when a cell, tissue, organ, or organ system self-adjusts in response to an environmental change.

Receptor

The component of a homeostatic control system that detects a stimulus or environmental change.

Effector

The structure in a homeostatic control system that brings about cellular or physiological changes to alter the stimulus.

Negative Feedback Mechanism Graph

A graph representing a system where the resulting action moves in the opposite direction of the stimulus, maintaining the variable fluctuating within a normal range around a set point.

Positive Feedback Mechanism Graph

A graph illustrating a process where a stimulus is reinforced to move a variable in the same direction until a climactic event occurs, after which homeostasis is restored.

Atom

The smallest particle that exhibits the unique characteristics of a chemical element.

Isotopes

Versions of an element that contain the same number of protons but different numbers of neutrons.

Half-Life

The time required for half of a given amount of a radioactive isotope to undergo decay.

Cation

A positively charged ion formed when an atom loses one or more electrons.

Anion

A negatively charged ion formed when an atom gains one or more electrons.

Ionic Bond

A chemical bond created by the electrostatic attraction between oppositely charged cations and anions following electron transfer.

Covalent Bond

A strong chemical bond created when atoms share pairs of valence electrons.

Amphipathic Molecules

Molecules that contain both polar (hydrophilic) and nonpolar (hydrophobic) regions.

Hydrogen Bond

A weak attraction formed between a partially positive hydrogen atom and a partially negative atom in polar molecules.

Hydrolysis

A catabolic decomposition reaction that breaks down complex molecules through the addition of a water molecule.

Dehydration Synthesis

An anabolic reaction that combines smaller molecules into larger ones, resulting in the production of a water molecule.

Catabolism

The collective term for decomposition reactions in the body that break down molecules and release energy.

Anabolism

The collective term for synthesis reactions in the body that require energy to form new chemical bonds.

Enzymes

Biological catalysts that lower the activation energy required for biochemical reactions without being consumed or altered.

Exergonic Reaction

A chemical reaction that produces a net release of energy because the energy released exceeds the activation energy.

Endergonic Reaction

A chemical reaction that absorbs net energy because the activation energy required is greater than the energy produced.

Electrolytes

Soluble inorganic compounds whose dissociated ions conduct electrical currents in solution.

Hydrophilic

Substances such as charged ions and polar molecules that readily dissolve in or interact with water.

Hydrophobic

Substances such as nonpolar molecules, fats, and oils that do not interact with or dissolve in water.

Acid

A proton donor that dissociates in water to release $H^+$ and an anion, increasing the concentration of free $H^+$.

Base

A proton acceptor that binds free $H^+$ when added to a solution, decreasing the concentration of free $H^+$.

Buffer

A chemical substance or system that helps prevent drastic changes in $pH$ by accepting or donating $H^+$ ions.

Glycogenesis

The formation of glycogen from individual glucose monomers, performed by liver and skeletal muscle cells to store excess glucose.

Glycogenolysis

The hydrolysis of stored glycogen into individual glucose monomers to meet cellular energy needs.

Gluconeogenesis

The metabolic process in which the liver creates new glucose from non-carbohydrate precursors.

Isomers

Molecules that possess identical molecular formulas but differ in their structural arrangements.

Triglycerides

Lipids consisting of one glycerol molecule linked to three fatty acid chains, serving as the primary form for long-term energy storage.

Eicosanoids

A class of locally acting lipids derived from dietary arachidonic acid, including leukotrienes and prostaglandins.

Steroids

Lipids composed of hydrocarbons arranged in a characteristic four-ring structure, serving as cell membrane components and signaling hormones.

Peptide Bond

A covalent bond formed via dehydration synthesis between the carboxylic acid group of one amino acid and the amine group of another.

Primary Structure

The specific linear sequence of amino acids joined together by peptide bonds in a polypeptide chain.

Secondary Structure

The localized folding or coiling of a polypeptide chain into alpha helixes or beta sheets due to hydrogen bonding.

Tertiary Structure

The overall three-dimensional shape of a protein, stabilized by interactions among the functional R groups of amino acids.

Quaternary Structure

The structural complex formed by the interaction and assembly of two or more separate polypeptide chains.

Protein Denaturation

A major conformational shape change in a protein caused by extreme temperature or $pH$, resulting in a loss of biological function.

Adenosine Triphosphate (ATP)

A high-energy nucleotide composed of adenosine and three phosphate groups, serving as the principal energy currency of the cell.