Human Biology: Tissues, Organ Systems, and Homeostasis

Vocabulary flashcards based on Chapter 4 of Human Biology (Mader/Windelspecht), covering tissues, organ systems, anatomical terms, and homeostasis.

Tissue

A collection of cells of the same type that perform a common function.

Connective tissue

A major tissue type that binds and supports body parts.

Muscular tissue

A major tissue type specialized to contract to move the body and its parts.

Nervous tissue

A major tissue type that conducts nerve impulses.

Epithelial tissue

A major tissue type that covers body surfaces and lines body cavities.

Ground substance

Noncellular material between the cells in connective tissue that varies in consistency from solid to fluid.

Collagen fibers

Protein fibers in connective tissue that are flexible and strong.

Reticular fibers

Thin, highly branched collagen fibers that form a network in connective tissue.

Elastic fibers

Protein fibers containing elastin that stretch and recoil.

Fibroblast

A type of cell in connective tissue that divides to produce other types of cells and fibers.

Matrix

The combination of ground substance and protein fibers in connective tissue.

Adipocytes

Cells in adipose tissue that are filled with liquid fat.

Tendons

Dense fibrous connective tissue that connects muscles to bones.

Ligaments

Dense fibrous connective tissue that connects bones to bones at joints.

Cartilage

A type of supportive connective tissue that is more flexible than bone because it lacks mineralization of the matrix.

Lacunae

Small chambers in which chondrocytes and osteocytes are located.

Hyaline cartilage

The most common type of cartilage, containing fine collagen fibers; found in the nose, ends of long bones, and fetal skeleton.

Elastic cartilage

Cartilage containing many elastic fibers; found in the outer ear.

Fibrocartilage

Cartilage with strong collagen fibers found in the disks between vertebrae and the knee.

Osteons

Cylindrical structural units found in compact bone.

Plasma

The fluid matrix of blood.

Erythrocytes

Red blood cells that carry oxygen.

Leukocytes

White blood cells that fight infection.

Thrombocytes

Platelets, which are pieces of cells that clot blood.

Lymph

A fluid connective tissue derived from the fluids of surrounding tissues, contained in lymphatic vessels.

Skeletal muscle

Striated, voluntarily controlled muscle tissue attached to the skeleton by tendons.

Smooth muscle

Non-striated, spindle-shaped, involuntarily controlled muscle found in the walls of viscera and blood vessels.

Cardiac muscle

Involuntary, striated muscle found only in the walls of the heart with branched cells connected by intercalated disks.

Neuron

A specialized cell of the nervous tissue consisting of dendrites, a cell body, and an axon.

Dendrites

Parts of a neuron that carry information toward the cell body.

Axon

Part of a neuron that conducts nerve impulses away from the cell body.

Neuroglia

Cells in nervous tissue that support and nourish neurons, outnumbering them $9$ to $1$.

Basement membrane

A layer that anchors epithelial tissue on one side.

Simple squamous epithelium

A single layer of flattened cells found in the lungs and blood vessel walls for gas exchange.

Pseudostratified columnar epithelium

Epithelium that appears stratified but every cell touches the basement membrane; often has cilia and is found in the trachea.

Exocrine glands

Glands that secrete their products into ducts, such as sweat or salivary glands.

Endocrine glands

Glands that secrete hormones directly into the bloodstream and have no ducts.

Transitional epithelia

Epithelial cells that change shape from cuboidal to squamous in response to tension.

Ventral (Anterior)

Anatomical term referring to the front of the body.

Dorsal (Posterior)

Anatomical term referring to the back of the body.

Proximal

Anatomical term meaning closer to the trunk of the body when referring to an appendage.

Distal

Anatomical term meaning away from the trunk of the body when referring to an appendage.

Pleurae

Serous membranes that line the thoracic cavity and cover the lungs.

Pericardium

Serous membrane that forms the pericardial sac and covers the heart.

Peritoneum

Serous membrane that lines the abdominal cavity and covers its organs.

Meninges

Connective tissue membranes in the dorsal cavity that surround the brain and spinal cord.

Epidermis

The thin, outermost layer of the skin made of stratified squamous epithelium.

Melanocytes

Epidermal cells that produce melanin to provide skin color and protection from UV light.

Dermis

The thick, inner layer of the skin made of dense fibrous connective tissue containing collagen and elastic fibers.

Sebaceous glands

Oil glands that produce sebum to soften hair and skin and retard bacterial growth.

Sudoriferous glands

Sweat glands located in the dermis that help regulate body temperature.

Homeostasis

The maintenance of a relatively constant internal environment within a narrow range of normal values.

Negative feedback

The primary mechanism of homeostasis where the output of the system turns down or off the production.

Positive feedback

A mechanism that brings about a change in the same direction as the original stimulus, such as during childbirth.