Anatomy and Physiology - Chapters 1, 2, and 3

Vocabulary practice flashcards covering Introduction to Anatomy & Physiology, Chemical Level of Organization, and Cellular Level of Organization.

Homeostasis

The presence of a relatively constant internal environment, maintained through physiological adjustments to preserve stability in variable external conditions.

Gross Anatomy

The visual study of large body structures and features that can be seen without magnification, such as organs and limbs; also known as macroscopic anatomy.

Microscopic Anatomy

The study of body structures that cannot be seen without magnification, such as cells and molecules.

Receptor

A sensor component in homeostatic regulation that detects environmental changes or stimuli.

Control Center

An integration center component in homeostatic regulation that processes information received from a receptor and sends out response commands.

Effector

A component in homeostatic regulation that carries out an action in response to a command from the control center to restore normal conditions.

Negative Feedback

The primary homeostatic mechanism in which the body senses a change and activates effector mechanisms to reverse that change, bringing conditions back to the set point.

Positive Feedback

A homeostatic mechanism that enhances or amplifies a sensed change in the same direction, temporarily moving the body away from the set point to accomplish a specific task.

Epithelial Tissue

A primary tissue type that covers exposed body surfaces, lines internal passageways and chambers, and produces glandular secretions.

Connective Tissue

A primary tissue type that fills internal spaces, provides structural support, and stores energy, characterized by cells surrounded by an extracellular matrix composed of protein fibers and ground substance.

Muscle Tissue

A primary tissue type specialized to contract forcefully to produce active skeletal movement, maintain blood flow, move materials internally, and stabilize body temperature.

Nervous Tissue

A primary tissue type specialized to conduct electrical impulses and carry information or instructions throughout the body.

Histology

The microscopic study of tissues.

Supine

Position describing a body lying down in the anatomical position face up.

Prone

Position describing a body lying down in the anatomical position face down.

Matter

Anything that takes up space and has mass.

Atom

The smallest stable unit of matter, composed of subatomic particles including protons, neutrons, and electrons.

Proton

A subatomic particle with a positive electrical charge ($p^+$) located within the nucleus of an atom.

Neutron

An uncharged or neutral subatomic particle ($n$ or $n^0$) located within the nucleus of an atom.

Electron

A subatomic particle with a negative electrical charge ($e^-$) orbiting the nucleus in the electron cloud.

Atomic Number

The total number of protons contained in the nucleus of an atom.

Mass Number

The total combined number of protons and neutrons in the nucleus of an atom.

Isotope

Atoms of the same element that contain an identical number of protons but a variable number of neutrons.

Valence Shell

The outermost electron shell of an atom whose electrons determine the atom's chemical reactivity and bonding properties.

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 electrical attraction between oppositely charged ions following an electron transfer.

Covalent Bond

A chemical bond formed when atoms stabilize their valence shells by sharing electrons.

Nonpolar Covalent Bond

A covalent bond in which shared electrons are shared equally between atoms, producing an electrically neutral molecule.

Polar Covalent Bond

A covalent bond featuring unequal sharing of electrons, giving specific regions of the molecule slight positive or negative charges.

Hydrogen Bond

A weak attraction between a partial positive charge on a hydrogen atom of one polar molecule and a partial negative charge on another molecule.

Electrolytes

Soluble inorganic ions that conduct an electrical current in solution and are essential for cellular electrical activity, fluid balance, and pH balance.

Hydrophilic

Refers to molecules that are attracted to and readily interact with or dissolve in water ('water loving').

Hydrophobic

Refers to nonpolar molecules that do not readily interact with or dissolve in water ('water fearing').

Acid

A solute that acts as a proton donor by releasing hydrogen ions ($H^+$) in solution, resulting in a pH below $7.0$.

Base

A solute that acts as a proton acceptor by removing hydrogen ions ($H^+$) from solution or releasing hydroxide ions ($OH^-$), resulting in a pH above $7.0$.

Buffer

A compound that stabilizes the pH of a solution by removing or adding $H^+$ ions to resist changes in pH.

Decomposition Reaction

A chemical reaction that breaks larger molecules into smaller fragments by cleaving chemical bonds.

Synthesis Reaction

A chemical reaction that creates new chemical bonds to assemble smaller molecules into larger, more complex structures.

Activation Energy

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

Enzyme

A specialized protein that acts as a biological catalyst to lower the activation energy of chemical reactions without being consumed in the process.

Monosaccharides

Simple sugar carbohydrates containing 3 to 7 carbon atoms, such as glucose, that serve as immediate energy sources.

Polysaccharides

Complex carbohydrates formed by long chains of covalently bonded monosaccharides, such as starch or glycogen.

Triglycerides

Lipids consisting of three fatty acid chains bound to a single molecule of glycerol, used for long-term energy storage, insulation, and protection.

Phospholipids

Amphiphilic lipids composed of a hydrophilic phosphate head and two hydrophobic fatty acid tails, forming the structural basis of cell membranes.

Denaturation

An irreversible change in a protein's three-dimensional shape caused by extreme environmental changes like high temperature or pH shifts, leading to loss of function.

Adenosine Triphosphate (ATP)

The primary high-energy compound in cells, consisting of adenine, ribose, and three phosphate groups, used to store and transfer cellular energy.

Cytosol

The fluid portion of the cytoplasm, also known as intracellular fluid (ICF), containing dissolved nutrients, ions, and proteins.

Nucleus

The central membranous organelle that stores and processes genetic information (DNA), controls cellular operations, and directs protein synthesis.

Ribosomes

Nonmembranous organelles composed of RNA and proteins that synthesize polypeptide chains during protein synthesis.

Rough Endoplasmic Reticulum (RER)

A membranous network studded with fixed ribosomes that functions in synthesizing, modifying, and packaging proteins.

Smooth Endoplasmic Reticulum (SER)

A membranous network lacking ribosomes that synthesizes lipids, steroid hormones, and carbohydrates, as well as storing materials and detoxifying cells.

Golgi Apparatus

An organelle consisting of stacks of flattened membranous chambers (cisternae) that modifies, packages, and ships products from the RER in vesicles.

Lysosomes

Vesicles produced by the Golgi apparatus containing digestive enzymes that break down damaged organelles, debris, and extracellular pathogens.

Peroxisomes

Vesicles containing degradative enzymes that break down fatty acids and organic compounds while neutralizing toxic byproducts like hydrogen peroxide.

Mitochondria

Double-membraned organelles responsible for producing approximately $950\%$ of cellular ATP through aerobic metabolism.

Microvilli

Nonmembranous, finger-like extensions of the plasma membrane supported by microfilaments that increase cell surface area for absorption.

Centrioles

Short, cylindrical microtubule structures located in the centrosome that organize and coordinate DNA movement during nuclear division.

Cilia

Long, cylindrical membrane projections supported by microtubules that move fluids and secretions across cell surfaces.

Diffusion

The passive physical movement of solutes from an area of higher concentration to an area of lower concentration down a concentration gradient.

Osmosis

The net diffusion of water molecules across a selectively permeable membrane toward the side with a higher solute concentration.

Hypotonic Solution

A solution with a lower solute concentration than the cytoplasm of a cell, causing water to enter the cell via osmosis, leading to swelling and possible lysis.

Hypertonic Solution

A solution with a higher solute concentration than the cytoplasm of a cell, causing water to move out of the cell via osmosis, leading to crenation.

Isotonic Solution

A solution with a solute concentration equal to that of the cytoplasm, producing no net osmotic movement of water.

Facilitated Diffusion

A passive carrier-mediated transport process in which a transmembrane carrier protein moves a specific solute across the plasma membrane down its concentration gradient.

Active Transport

A carrier-mediated transport process that consumes energy (ATP) to move solutes across a membrane against their concentration gradient.

Endocytosis

An active vesicular process that imports bulk materials or fluids into the cell by forming membrane-bound vesicles.

Exocytosis

An active vesicular process that exports cellular wastes or secretory products out of the cell by fusing internal vesicles with the plasma membrane.

Gene

A functional unit of heredity containing all the DNA nucleotides required to produce a specific functional protein.

Transcription

The nuclear process of protein synthesis in which RNA polymerase uses a DNA strand as a template to form a complementary messenger RNA (mRNA) strand.

Translation

The cytoplasmic process of protein synthesis in which ribosomes read mRNA codons and tRNA molecules supply matching amino acids to construct a polypeptide chain.

Mitosis

The division of a somatic cell's nucleus that produces two genetically identical daughter cells, each containing 46 chromosomes.

Meiosis

The specialized cell division occurring only in reproductive cells that produces four genetically unique daughter cells (gametes), each containing 23 chromosomes.

Cytokinesis

The physical division of the cytoplasm into two distinct daughter cells during cell division, characterized by the formation of a cleavage furrow.