Anatomy and Physiology Introductory Foundations

This flashcard set covers essential vocabulary from Anatomy and Physiology, including levels of organization, homeostatic control mechanisms, anatomical terminology, chemical foundations of life, and cellular transport mechanisms.

Anatomy

science that studies the form and composition of the body’s structures

Physiology

science that studies the chemistry, biochemistry, and physics of the body’s functions

Cell

smallest independently functioning unit of all organisms; in animals, a cell contains cytoplasm, composed of fluid and organelles

Tissue

group of similar or closely related cells that act together to perform a specific function

Organ

functionally distinct structure composed of two or more types of tissues

Organ System

group of organs that work together to carry out a particular function

Organism

living being that has a cellular structure and that can independently perform all physiologic functions necessary for life

Homeostasis

steady state of body systems that living organisms maintain

Set Point

ideal value for a physiological parameter; the level or small range within which a physiological parameter such as blood pressure is stable and optimally healthful, that is, within its parameters of homeostasis

Normal Range

range of values around the set point that do not cause a reaction by the control center

Sensor (also, receptor)

reports a monitored physiological value to the control center

Control Center

compares values to their normal range; deviations cause the activation of an effector

Effector

organ that can cause a change in a value

Negative Feedback

homeostatic mechanism that tends to stabilize an upset in the body’s physiological condition by preventing an excessive response to a stimulus, typically as the stimulus is removed

Positive Feedback

mechanism that intensifies a change in the body’s physiological condition in response to a stimulus

Anatomical Position

standard reference position used for describing locations and directions on the human body

Anterior (ventral)

describes the front or direction toward the front of the body

Posterior (dorsal)

describes the back or direction toward the back of the body

Superior (cranial)

describes a position above or higher than another part of the body proper

Inferior (caudal)

describes a position below or lower than another part of the body proper; near or toward the tail (in humans, the coccyx, or lowest part of the spinal column)

Medial

describes the middle or direction toward the middle of the body

Lateral

describes the side or direction toward the side of the body

Proximal

describes a position nearer to the point of attachment or the trunk of the body

Distal

describes a position farther from the point of attachment or the trunk of the body

Superficial

describes a position nearer to the surface of the body

Deep

describes a position farther from the surface of the body

Plane

imaginary two-dimensional surface that passes through the body

Sagittal Plane

two-dimensional, vertical plane that divides the body or organ into right and left sides

Frontal Plane

two-dimensional, vertical plane that divides the body or organ into anterior and posterior portions

Transverse Plane

two-dimensional, horizontal plane that divides the body or organ into superior and inferior portions

Oblique Plane

two-dimensional, vertical plane that intersects the body at an angle and is not parallel of perpendicular to any of the other three commonly used planes

Dorsal Cavity

posterior body cavity that houses the brain and spinal cord; also referred to the posterior body cavity

Ventral Cavity

larger body cavity located anterior to the posterior (dorsal) body cavity; includes the serous membrane-lined pleural cavities for the lungs, pericardial cavity for the heart, and peritoneal cavity for the abdominal and pelvic organs; also referred to as anterior body cavity

Cranial Cavity

division of the posterior (dorsal) cavity that houses the brain

Spinal Cavity (vertebral cavity)

division of the dorsal cavity that houses the spinal cord

Thoracic Cavity

division of the anterior (ventral) cavity that houses the heart, lungs, esophagus, and trachea

Abdominopelvic Cavity

division of the anterior (ventral) cavity that houses the abdominal and pelvic viscera

Pleura

serous membrane that lines the pleural cavity and covers the lungs

Pericardium

sac that encloses the heart

Peritoneum

serous membrane that lines the abdominopelvic cavity and covers the organs found there

Matter

physical substance; that which occupies space and has mass

Element

substance that cannot be created or broken down by ordinary chemical means

Atom

smallest unit of an element that retains the unique properties of that element

Proton

heavy subatomic particle having a positive charge and found in the atom’s nucleus

Neutron

heavy subatomic particle having no electrical charge and found in the atom’s nucleus

Electron

subatomic particle having a negative charge and nearly no mass; found orbiting the atom’s nucleus

Atomic Number

number of protons in the nucleus of an atom

Mass Number

sum of the number of protons and neutrons in the nucleus of an atom

Isotope

one of the variations of an element in which the number of neutrons differ from each other

Electron Shell

area of space a given distance from an atom’s nucleus in which electrons are grouped

Valence Shell

outermost electron shell of an atom

Ion

atom with an overall positive or negative charge

Cation

atom with a positive charge

Anion

atom with a negative charge

Ionic Bond

attraction between an anion and a cation

Covalent Bond

chemical bond in which two atoms share electrons, thereby completing their valence shells

Molecule

two or more atoms covalently bonded together

Compound

substance composed of two or more different elements joined by chemical bonds

Polar Molecule

molecule with regions that have opposite charges resulting from uneven numbers of electrons in the nuclei of the atoms participating in the covalent bond

Hydrogen Bond

dipole-dipole bond in which a hydrogen atom covalently bonded to an electronegative atom is weakly attracted to a second electronegative atom

Chemical Energy

form of energy that is absorbed as chemical bonds form, stored as they are maintained, and released as they are broken

Reactant

one or more substances that enter into the reaction

Product

one or more substances produced by a chemical reaction

Synthesis Reaction

type of anabolic reaction in which two or more atoms or molecules bond, resulting in the formation of a larger molecule

Decomposition Reaction

type of catabolic reaction in which one or more bonds within a larger molecule are broken, resulting in the release of smaller molecules or atoms

Activation Energy

amount of energy greater than the energy contained in the reactants, which must be overcome for a reaction to proceed

Catalyst

substance that increases the rate of a chemical reaction without itself being changed in the process

Enzyme

protein or RNA that catalyzes chemical reactions

Inorganic Compound

substance that does not contain both carbon and hydrogen

Solution

homogeneous liquid mixture in which a solute is dissolved into molecules within a solvent

Acid

compound that releases hydrogen ions ($H^+$) in solution

Base

compound that accepts hydrogen ions ($H^+$) in solution

pH

negative logarithm of the hydrogen ion ($H^+$) concentration of a solution

Buffer

solution containing a weak acid or a weak base that opposes wide fluctuations in the pH of body fluids

Organic Compound

substance that contains both carbon and hydrogen

Carbohydrate

class of organic compounds built from sugars, molecules containing carbon, hydrogen, and oxygen in a $1\text{-}2\text{-}1$ ratio

Lipid

class of nonpolar organic compounds built from hydrocarbons and distinguished by the fact that they are not soluble in water

Protein

class of organic compounds that are composed of many amino acids linked together by peptide bonds

Amino Acid

building block of proteins; characterized by an amino and carboxyl functional groups and a variable side-chain

Adenosine Triphosphate (ATP)

nucleotide containing ribose and an adenine base that is essential in energy transfer

Cell Membrane (plasma membrane)

membrane surrounding all animal cells, composed of a lipid bilayer interspersed with various molecules

Intracellular Fluid (icf)

fluid in the cytosol of cells

Extracellular Fluid (ecf)

fluid exterior to cells; includes the interstitial fluid, blood plasma, and fluid found in other reservoirs in the body

Selective Permeability

feature of any barrier that allows certain substances to cross but excludes others

Concentration Gradient

difference in the concentration of a substance between two regions

Passive Transport

form of transport across the cell membrane that does not require input of cellular energy

Diffusion

movement of a substance from an area of higher concentration to one of lower concentration

Facilitated Diffusion

diffusion of a substance with the aid of a membrane protein

Osmosis

diffusion of water molecules down their concentration gradient across a selectively permeable membrane

Hypertonic

describes a solution concentration that is higher than a reference concentration

Isotonic

describes a solution concentration that is the same as a reference concentration

Hypotonic

describes a solution concentration that is lower than a reference concentration

Active Transport

form of transport across the cell membrane that requires input of cellular energy

Sodium-Potassium Pump (also, Na+/K+ ATP-ase)

membrane-embedded protein pump that uses ATP to move $Na^+$ out of a cell and $K^+$ into the cell

Endocytosis

import of material into the cell by formation of a membrane-bound vesicle

Phagocytosis

endocytosis of large particles

Receptor-Mediated Endocytosis

endocytosis of ligands attached to membrane-bound receptors

Exocytosis

export of a substance out of a cell by formation of a membrane-bound vesicle

Cytoplasm

internal material between the cell membrane and nucleus of a cell, mainly consisting of a water-based fluid called cytosol, within which are all the other organelles and cellular solute and suspended materials

Cytosol

clear, semi-fluid medium of the cytoplasm, made up mostly of water