Human Anatomy and Physiology Midterm Review

Flashcards covering the essential vocabulary and concepts for the anatomy and physiology midterm, including chemistry, cell biology, tissues, and the integumentary and skeletal systems.

Levels of Organization

The structural hierarchy of the human body, ranging from atoms and molecules to cells, tissues, organs, systems, and the complete organism.

Negative Feedback

A homeostatic control mechanism that reverses a change in a controlled condition to maintain internal stability.

Positive Feedback

A homeostatic control mechanism that strengthens or reinforces a change in one of the body's controlled conditions.

Proton

A subatomic particle with a positive charge located in the nucleus of an atom.

Neutron

A subatomic particle with no charge (neutral) located in the nucleus of an atom.

Electron

A subatomic particle with a negative charge located in shells or orbitals surrounding the nucleus.

Atomic Number

The number of protons in the nucleus of an atom, identifying the element.

Mass Number

The sum of the number of protons and neutrons in an atom's nucleus.

Ion

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

Isotope

Atoms of the same element that have the same number of protons but different numbers of neutrons.

Inorganic Compounds

Biologically important substances that typically lack carbon-hydrogen bonds, such as water, salts, acids, and bases.

Organic Compounds

Carbon-containing compounds essential to life, including carbohydrates, lipids, proteins, and nucleic acids.

Saturated Fats

Lipids with hydrocarbon chains containing only single bonds, typically solid at room temperature.

Unsaturated Fats

Lipids with hydrocarbon chains containing one or more double bonds, typically liquid at room temperature.

Monosaccharide

The simplest form of carbohydrate (single sugar), such as glucose, serving as a building block for more complex sugars.

Disaccharide

A carbohydrate formed by the combination of two monosaccharides through dehydration synthesis.

Polysaccharide

Complex carbohydrates consisting of long chains of monosaccharides, such as glycogen or starch.

Catabolic

Chemical reactions that break down complex organic molecules into simpler ones, usually releasing energy.

Anabolic

Chemical reactions that combine simple molecules to form more complex structural and functional components, usually requiring energy.

Exergonic Reaction

A chemical reaction that releases more energy than it absorbs.

Endergonic Reaction

A chemical reaction that requires an absorption of energy to proceed.

Dehydration Synthesis

A chemical reaction where two molecules are bonded together with the removal of a water molecule.

Hydrolysis

A chemical reaction that breaks bonds between large molecules by the addition of water.

Enzymes

Biological catalysts, typically proteins, that speed up chemical reactions by lowering activation energy.

Acidic Solution

A solution with a pH below $7.0$ containing a higher concentration of hydrogen ions ($H^+$).

Basic (Alkaline) Solution

A solution with a pH above $7.0$ containing a lower concentration of hydrogen ions ($H^+$).

Interphase

The period of the cell cycle between divisions, consisting of three stages where the cell grows and replicates its DNA.

Mitosis

The process of nuclear division that results in two identical daughter nuclei, necessary for growth and tissue repair.

Plasma Membrane

A phospholipid bilayer with embedded proteins that regulates the transport of materials entering and exiting the cell.

Active Transport

The movement of substances across a cell membrane against a concentration gradient, requiring energy (ATP).

Passive Transport

The movement of substances across a cell membrane along a concentration gradient without the expenditure of cellular energy.

Tonicity

The ability of a surrounding solution to cause a cell to gain or lose water based on solute concentration.

Transcription

The process occurring in the nucleus where a specific sequence of DNA is copied into a complementary strand of RNA.

Translation

The process occurring at the ribosome where the mRNA sequence is used to assemble a specific sequence of amino acids into a protein.

Codon

A three-nucleotide sequence on messenger RNA (mRNA) that specifies a particular amino acid.

Anticodon

A triplet of nucleotides on transfer RNA (tRNA) that is complementary to a specific codon on mRNA.

Epithelial Tissue

Tissue characterized by closely packed cells arranged in layers (shapes and layers) that covers body surfaces and lines cavities.

Muscle Tissue

Tissue types (skeletal, cardiac, smooth) specialized for contraction and generating force.

Epidermis

The outermost, superficial layer of the skin composed of epithelial cells.

Dermis

The deeper layer of the skin containing connective tissue, blood vessels, and sensory receptors.

Subcutaneous Area

Also known as the hypodermis, the layer beneath the dermis containing adipose tissue and providing insulation/anchoring.

Osteoclasts

Cells that break down (resorb) bone matrix to release minerals into the blood.

Osteoblasts

Cells that function in bone formation by depositing bone matrix.

Osteocytes

Mature bone cells that maintain the daily metabolism of bone tissue.

PTH (Parathyroid Hormone)

The hormone that increases blood calcium levels by stimulating osteoclast activity.

Calcitonin

The hormone that helps lower blood calcium levels by inhibiting osteoclasts and encouraging calcium deposition in bone.

Compact Bone

Dense bone tissue composed of osteons that provides protection and support, usually found on the exterior of bones.

Spongy Bone

Bone tissue consisting of a lattice called trabeculae, found in the interior of bones and containing red bone marrow.