Test Prep #2

Tissues

Group of cells similar in structure working together to perform a common function.

Four types of Tissue

1) Connective Tissue, 2) Epithelial Tissue, 3) Muscle Tissue, 4) Nervous Tissue.

Epithelial tissue

Covers exposed surfaces, lines internal passageways, and forms glands.

Apical Surface

The surface of epithelial cells that is always on top.

Goblet Cells

A unicellular gland responsible for the secretion of mucus.

Cilia

Hair-like structures used to move substances across epithelial surfaces.

Microvilli

Tiny projections that increase surface area for absorption and secretion.

Keratinized

Dead cells filled with keratin that protect against abrasion.

Basal Surface

The surface of epithelial cells that have a basement membrane.

Basement Membrane

A layer made of collagen and glycoprotein that supports epithelial tissue and determines exchange with connective tissue.

Avascular

Lacking blood vessels; epithelial tissues receive nutrients from connective tissue below.

Regeneration

The ability of epithelial tissue to quickly replace lost cells.

Nerve Endings

Sensory receptors usually present in high quantities in epithelial tissues.

Squamous Cell Epithelia

Epithelial cells that are thin and flat.

Cuboidal Epithelia

Epithelial cells that are square-shaped.

Columnar Epithelia

Epithelial cells that are tall and slender.

Simple Epithelium

A type of epithelium consisting of a single layer of cells.

Stratified Epithelium

A type of epithelium consisting of multiple layers of cells.

Simple Squamous Epithelium

Epithelial tissue specializing in absorption and diffusion found in lungs and kidney tubules.

Mesothelium

Epithelial tissue that lines body cavities.

Endothelium

Epithelial tissue that lines heart and blood vessels.

Simple Cuboidal Epithelium

Epithelial tissue found in glands and ducts.

Simple Columnar Epithelium

Epithelial tissue involved in absorption and secretion found in the stomach and intestines.

Stratified Squamous Epithelium

Epithelial tissue that protects against abrasion found in skin and mouth.

Stratified Cuboidal Epithelium

Epithelial tissue that lines sweat ducts and mammary glands.

Stratified Columnar Epithelium

Epithelial tissue that provides protection, found in mammary glands and urethra.

Transitional Epithelium

Epithelial tissue that can stretch and recoil, found in the bladder.

Pseudostratified Columnar Epithelium

Epithelial tissue that appears stratified but is not; found in the respiratory tract.

Endocrine Glands

Glands that release hormones directly into the blood, without ducts.

Exocrine Glands

Glands that produce secretions onto epithelial surfaces through ducts.

Merocrine Secretion

Secretion released by exocytosis from the Golgi apparatus.

Apocrine Secretion

Secretion involving part of the cell's cytoplasm being shed along with the product.

Holocrine Secretion

Secretion that occurs when gland cells burst, killing them.

Glandular Epithelium

Type of epithelium specialized for secretion.

Serous Glands

Glands that produce watery secretions.

Mucous Glands

Glands that secrete mucins.

Mixed Exocrine Glands

Glands that produce both serous and mucous secretions.

Connective Tissue

Connects epithelium to the rest of the body and provides structure.

Matrix

The extracellular material in connective tissue consisting of fibers and ground substance.

Collagen

Strong and flexible fibers found in connective tissue.

Elastic Fibers

Flexible fibers that can stretch and return to their original length.

Reticular Fibers

Fine collagen fibers forming a network in connective tissues.

Ground Substance

The medium in which connective tissue cells are embedded.

Blood

A type of connective tissue with a watery matrix.

Areolar Tissue

Loose connective tissue with hyaluronic acid that is viscous.

Cartilage

A type of connective tissue with a gel-like ground substance.

Bone

Hard connective tissue with a mineralized matrix.

Connective Tissue Proper

Tissues that connect and protect; includes loose and dense connective tissues.

Fluid Connective Tissues

Tissues that transport materials, like blood and lymph.

Supportive Connective Tissues

Tissues that provide structural strength, such as cartilage and bone.

Fibroblasts

Cells that synthesize the extracellular matrix and collagen in connective tissue.

Chondroblasts

Cells that produce cartilage.

Osteoblasts

Bone-building cells.

Hemopoietic Stem Cells

Stem cells in blood that give rise to various blood cells.

Fibrocytes

Cells that maintain connective tissue fibers.

Macrophages

Large immune cells that engulf pathogens and damaged cells.

Adipocytes

Fat cells that store energy.

Mesenchymal Cells

Stem cells that respond to injury in connective tissue.

Melanocytes

Cells that produce the pigment melanin.

Mast Cells

Cells involved in inflammation and allergic responses.

Lymphocytes

Specialized immune cells in the lymphatic system.

Microphages

Small phagocytic blood cells.

Collagen Fibers

Most abundant fibers in connective tissue, strong and flexible.

Reticular Fibers

Fibers that resist force from multiple directions.

Elastic Fibers

Fibers that return to their original length after stretching.

Embryonic Connective Tissues

Tissues not found in adults; includes mesenchyme and mucous connective tissue.

Loose Connective Tissue

The packing material of the body, includes areolar, adipose, and reticular tissues.

Areolar Tissue

Loose connective tissue found beneath epithelium.

Adipose Tissue

Loose connective tissue that stores fat and prevents heat loss.

Reticular Tissue

Loose connective tissue providing support in organs like the spleen.

Dense Connective Tissue

Tightly packed connective tissue with high collagen content.

Dense Regular Connective Tissue

Tightly packed, parallel collagen fibers found in tendons and ligaments.

Dense Irregular Connective Tissue

Interwoven collagen fibers providing strength in various directions.

Elastic Tissue

Connective tissue consisting mainly of elastic fibers.

Cartilage

Gel-like ground substance for shock absorption.

Hyaline Cartilage

Most common type of cartilage, reduces friction between bones.

Elastic Cartilage

Cartilage that bends easily, found in external ear.

Fibrous Cartilage

Limits movement and provides support in joints.

Bone Tissue

Strong, calcified tissue that provides support and structure.

Periosteum

Connective tissue covering bone surfaces.

Fluid Connective Tissues

Blood and lymph; transport materials throughout the body.

Skeletal Muscle

Voluntary muscle with striations, control movement.

Cardiac Muscle

Involuntary muscle found in the heart.

Smooth Muscle

Involuntary muscle that lines internal organs.

Neural Tissue

Specialized tissue for conducting electrical impulses.

Neurons

Cells responsible for electrical communication in neural tissue.

Neuroglia

Supporting cells in nervous tissue that maintain homeostasis.

Cell Body (Soma)

Contains the nucleus and is part of a neuron.

Dendrites

Branching structures of a neuron that receive signals.

Axon

Long extension of a neuron that transmits electrical impulses.

Membranes

Physical barriers lining or covering body parts.

Mucous Membranes

Membranes that line cavities opening to the exterior; contain goblet cells.

Serous Membranes

Membranes lining closed body cavities, secreting serous fluid.

Cutaneous Membrane

Skin; the largest organ of the body.

Synovial Membranes

Membranes lining joint cavities and producing synovial fluid.

Integumentary System

The largest organ system comprised of skin and accessory structures.

Cutaneous Membrane

Skin; made of keratinized stratified squamous epithelium.

Subcutaneous Layer

Loose connective tissue beneath the dermis.

Keratinocytes

Majority of cells in the epidermis, produce keratin.

Stratum Basale

Lowest layer of the epidermis where cell division occurs.