Human Anatomy & Physiology - Chapter 1

These flashcards cover key vocabulary terms and definitions related to Human Anatomy and Physiology, essential for understanding the content of the textbook.

Homeostasis

The ability to maintain a stable internal environment despite changes in external conditions.

Anatomy

The study of the structure of body parts and their relationships to one another.

Physiology

The study of the function of body parts and how they work together.

Tissue

Groups of similar cells that have a common function.

Cell

The smallest unit of life that can carry out all life processes.

Organ System

A group of organs that work together to perform complex functions for the body.

Negative Feedback Mechanism

A process that counteracts a change in a variable, returning it to its set point.

Positive Feedback Mechanism

A process that enhances or increases the change in a variable away from its set point.

Molecule

Two or more atoms bonded together.

Ion

An atom or molecule that has gained or lost one or more electrons, resulting in a net charge.

Covalent Bond

A chemical bond formed by the sharing of a pair of electrons between atoms.

Ionic Bond

A chemical bond formed through the transfer of electrons from one atom to another, resulting in electrically charged ions.

Hydrogen Bond

A weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in the other.

ATP (Adenosine Triphosphate)

The primary energy carrier in cells, used to store and transfer energy.

Dehydration Synthesis

A chemical reaction that combines small molecules (monomers) into larger molecules (polymers) while releasing water.

Hydrolysis

A chemical reaction that breaks down larger molecules into smaller molecules (monomers) by adding water.

pH Scale

A measure of the acidity or basicity of a solution, ranging from 0 (acidic) to 14 (basic), with 7 being neutral.

Electrolyte

Ionic compounds that dissociate into ions in solution and can conduct an electric current.

Organ

A discrete structure composed of at least two tissue types that performs a specific functional role for the body.

Organism

The highest level of biological organization, representing the sum total of all structural levels working together to maintain life.

Organelle

Small, specialized structures within a cell, such as mitochondria or ribosomes, that perform specific functions.

Metabolism

The sum total of all chemical reactions that occur within the body's cells.

Receptor

A sensor that monitors the environment and responds to changes (stimuli) by sending information to the control center.

Control Center

The component of a feedback system that determines the set point, analyzes input, and coordinates an appropriate response.

Effector

The component that carries out the control center's response to the stimulus, either depressing or enhancing it.

Enzyme

A biological catalyst, typically a protein, that speeds up the rate of chemical reactions without being consumed.

Organic Compound

A molecule that contains carbon and is typically found in or produced by living systems.

Inorganic Compound

Substances that generally lack carbon-hydrogen bonds, such as water (H_{2}O), salts, and many acids and bases.

Protein

Large organic molecules composed of amino acids that play many critical roles in the body, including structure, function, and regulation.

Carbohydrate

Organic molecules such as sugars and starches that serve as the primary source of energy for the body.

Lipid

Hydrophobic organic molecules, including fats and oils, used for long-term energy storage, insulation, and forming cell membranes.

Nucleic Acid

Large molecules, such as DNA and RNA, that are responsible for the storage and expression of genetic information.

Atom

The smallest unit of matter that retains the properties of an element, consisting of protons, neutrons, and electrons.

Anabolism

The metabolic process of building up larger, complex molecules from smaller ones, requiring an input of energy.

Catabolism

The metabolic process of breaking down complex molecules into simpler ones, resulting in the release of energy.

Superior (Cranial)

A directional term meaning toward the head end or upper part of a structure; above.

Inferior (Caudal)

A directional term meaning away from the head end or toward the lower part of a structure; below.

Anterior (Ventral)

A directional term meaning toward or at the front of the body; in front of.

Posterior (Dorsal)

A directional term meaning toward or at the back of the body; behind.

Sagittal Plane

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

Frontal (Coronal) Plane

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

Transverse Plane

A horizontal plane that divides the body or an organ into superior (upper) and inferior (lower) portions.

Buffer

A chemical substance or system that minimizes changes in pH by accepting or donating hydrogen ions (H^{+}).

Activation Energy

The minimum amount of energy required to initiate a chemical reaction.

Phospholipid

A specialized lipid molecule with a hydrophilic head and hydrophobic tails, acting as the primary component of cell membranes.