Anatomy, Physiology, and Chemical Basis of Life

Vocabulary flashcards covering anatomical terminology, body planes, cavities, atomic structure, isotopes, chemical bonding, pH balance, and metabolic concepts from Modules 1 and 2.

Distal

Describes a position in a limb that is farther from the point of attachment or the trunk of the body; for example, the crus is distal to the femur.

Superficial

Describes a position closer to the surface of the body; for example, the skin is superficial to the bones.

Deep

Describes a position farther from the surface of the body; for example, the brain is deep to the skull.

Section

A two-dimensional surface of a three-dimensional structure that has been cut.

Sagittal plane

A body plane that divides the body vertically into right and left sides.

Frontal plane (coronal plane)

A body plane that divides the body into anterior and posterior portions.

Transverse plane

A body plane that divides the body horizontally into upper and lower portions.

Dorsal cavity

The posterior main body compartment housing the cranial and spinal (vertebral) cavities.

Ventral cavity

The anterior main body compartment housing the thoracic and abdominopelvic cavities.

Serous membranes

Membranes such as the pleura, pericardium, and peritoneum that line walls and organs in thoracic and abdominopelvic cavities, reducing friction and providing protection.

Abdominal regions

Nine divisions of the abdomen created by two horizontal lines (below ribs and above pelvis) and two vertical lines dropped from the clavicles.

Abdominal quadrants

Four divisions of the abdomen created by one horizontal line and one vertical line intersecting at the umbilicus.

Protons

Subatomic particles that carry a positive charge and have a mass of $1$ mass unit.

Neutrons

Subatomic particles that carry a neutral charge and have a mass of $1$ mass unit.

Electrons

Subatomic particles that carry a negative charge and have low mass.

Hydrogen-1

A typical hydrogen atom whose nucleus contains $1$ proton and $0$ neutrons.

Deuterium ($^2\text{H}$)

A hydrogen isotope (Hydrogen-2) whose nucleus contains $1$ proton and $1$ neutron.

Tritium ($^3\text{H}$)

A hydrogen isotope (Hydrogen-3) whose nucleus contains $1$ proton and $2$ neutrons.

Element

A pure substance composed of atoms of one kind.

Atomic number

The number of protons in an atom, which determines its chemical properties.

Mass number

The total number of protons plus the number of neutrons in an atom.

Isotopes

Versions of elements based on differing mass numbers.

Radioisotopes

Isotopes with radioactive nuclei whose decay rate is expressed as a half-life.

Essential elements in the human body

Oxygen, Carbon, Hydrogen, and Nitrogen, which constitute the majority of body mass and serve as building blocks of life.

Organic molecules

Carbon-based compounds essential for life, including carbohydrates, proteins, lipids, and nucleic acids.

Covalent bonds

Chemical bonds formed by shared electrons between atoms.

Polar covalent bond

A covalent bond involving unequal sharing of electrons, creating molecules like water.

Nonpolar covalent bond

A covalent bond involving equal sharing of electrons, commonly found in lipids.

Hydrophilic

Water-loving compounds (hydro- = water, philos = loving) including ions and polar molecules that interact with water.

Hydrophobic

Water-fearing compounds (phobos = fear) including nonpolar molecules, fats, and oils that do not interact with water.

Hydrogen bonds

Weak chemical bonds essential for molecular stability, key in stabilizing DNA, proteins, and properties of water.

Acids

Substances that release $\text{H}^+$ ions, influencing stomach acidity.

Bases

Substances that accept $\text{H}^+$ ions or release $\text{OH}^-$ ions, key in neutralizing acids.

pH balance

A measure of acidity or alkalinity essential for enzyme activity and metabolic balance.

Buffers

Systems that stabilize the pH of solutions by neutralizing strong acids or strong bases, often involving a weak acid and its related salt.

Carbonic acid-bicarbonate buffer system

A major buffer system that plays a very important role in human pH control.

Metabolism

The collective chemical reactions occurring within an organism.

Catabolism

Energy-releasing metabolic reactions and pathways within an organism.

Anabolism

Energy-consuming metabolic reactions and processes within an organism.

Carbohydrates

Covalently bonded organic molecules containing Hydrogen, Carbon, and usually Oxygen that serve as primary energy sources.