Histology Part 1 (Lab 2)

What are the four primary tissue types?

Epithelial, connective, muscular, and nervous.

How must a specific tissue be named?

Use its full name, such as simple columnar epithelial tissue.

What are the characteristics of epithelial tissue?

Cellular, polar, avascular, and regenerative.

What are the functions of epithelial tissue?

Protection, absorption, secretion, and sensation.

Where is epithelial tissue found?

It covers internal and external surfaces, openings, and passageways.

How is epithelial tissue classified?

By the number of cell layers and the shape of its cells.

What do simple and stratified mean?

Simple has one layer; stratified has multiple layers.

What does squamous mean?

Flat cells that are much wider than they are tall.

What does cuboidal mean?

Cube-shaped cells with approximately equal height and width.

What does columnar mean?

Column-shaped cells that are taller than they are wide.

What identifies simple squamous epithelial tissue?

Flattened cells create a short path for rapid diffusion.

Where is simple squamous epithelial tissue found?

Lungs, kidneys, and the linings of blood vessels.

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Simple squamous epithelial tissue

What identifies simple cuboidal epithelial tissue?

Cuboidal cells allow passive transport, active absorption, and secretion.

Where is simple cuboidal epithelial tissue found?

Kidney tubules and smaller ducts of exocrine glands.

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Simple cuboidal epithelial tissue

What identifies non-ciliated simple columnar epithelial tissue?

Apical microvilli increase surface area for absorption and secretion.

Where is non-ciliated simple columnar epithelial tissue found?

Lining the digestive tract.

What identifies ciliated simple columnar epithelial tissue?

Apical cilia move material parallel to the tissue surface.

Where is ciliated simple columnar epithelial tissue found?

Bronchi, uterus, and uterine tubes.

What are goblet cells?

Single-celled glands that secrete mucins, which become mucus when exposed to water.

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Simple columnar epithelial tissue

What is the function of stratified squamous epithelial tissue?

Many layers provide mechanical protection and abrasion resistance.

Where is stratified squamous epithelial tissue found?

Skin, mouth, esophagus, and vagina.

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Stratified squamous epithelial tissue

What identifies stratified cuboidal epithelial tissue?

Usually two layers; protects and transports secretions in large gland ducts.

Where is stratified cuboidal epithelial tissue found?

Large ducts of mammary, salivary, and sweat glands.

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Stratified cuboidal epithelial tissue

What identifies stratified columnar epithelial tissue?

A rare tissue that provides protection and secretion.

Where is stratified columnar epithelial tissue found?

Male urethra and large ducts of exocrine glands.

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Stratified columnar epithelial tissue

What is the function of pseudostratified columnar epithelial tissue?

Secretion and propulsion of mucus.

Where are the two forms of pseudostratified columnar epithelial tissue found?

Ciliated in the trachea; non-ciliated in male ejaculatory ducts.

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Pseudostratified columnar epithelial tissue

What identifies transitional epithelial tissue?

It permits stretching.

Where is transitional epithelial tissue found?

Urinary bladder and ureters.

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Transitional epithelial tissue

What characterizes connective tissue?

Specialized cells embedded within a non-living matrix.

What makes up the connective tissue matrix?

Ground substance and protein fibers.

What makes up ground substance?

Interstitial fluid, cell-adhesion proteins, and proteoglycans.

What protein fibers occur in connective tissue?

Collagen, elastin, and reticulin.

What are the functions of connective tissue?

Framework, protection, support, energy storage, and immunity.

How is connective tissue classified?

By cell types, ground-substance composition, and protein-fiber types.

What are the three main divisions of connective tissue?

Connective tissue proper, supporting connective tissue, and fluid connective tissue.

How do loose and dense connective tissue differ?

Loose tissue has loosely arranged fibers; dense tissue has fibers in dense bundles.

What identifies areolar connective tissue?

Mostly fibroblasts with macrophages, mast cells, white blood cells, and all three fiber types.

What are the locations and functions of areolar connective tissue?

Forms lamina propria and wraps and cushions most organs.

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Areolar connective tissue

What identifies adipose connective tissue?

Modified areolar tissue dominated by adipocytes.

What are the functions and locations of adipose connective tissue?

Energy storage, cushioning, and insulation under skin and in the abdomen and breasts.

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Adipose connective tissue

What identifies reticular connective tissue?

Lymphocytes, mast cells, and stem cells supported by branching reticulin fibers.

Where is reticular connective tissue found?

Lymph nodes, bone marrow, and spleen.

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Reticular connective tissue

What identifies dense regular connective tissue?

Fibroblasts and collagen fibers arranged in long, parallel bundles.

What are the locations and function of dense regular connective tissue?

Tendons and ligaments; provides strength against force along one axis.

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Dense regular connective tissue

What identifies dense irregular connective tissue?

Fibroblasts and collagen bundles oriented in many directions.

What are the locations and function of dense irregular connective tissue?

Dermis, digestive submucosa, and capsules; resists force from many directions.

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Dense irregular connective tissue

What identifies cartilage?

Chondrocytes in lacunae within a rubbery matrix; completely avascular.

What identifies hyaline cartilage?

A relatively uniform matrix that provides cushioning, support, and reinforcement.

Where is hyaline cartilage found?

Ends of long bones, ribs, and trachea.

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Hyaline cartilage

What identifies elastic cartilage?

A matrix with many branched elastin fibers.

Where is elastic cartilage found?

External ear and epiglottis.

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Elastic cartilage

What identifies fibrous cartilage?

Parallel collagen fibers provide tensile strength and shock absorption.

Where is fibrous cartilage found?

Intervertebral discs and the knee joint.

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Fibrous cartilage

What identifies bone tissue?

Osteocytes in lacunae within a vascular matrix containing calcium, phosphorus, and collagen.

What are the function and forms of osseous connective tissue?

Supports and protects organs; occurs as compact and spongy bone.

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Osseous connective tissue

What identifies blood?

Red and white blood cells in a fluid matrix containing mainly albumin.

Where is blood found, and how do its cells stain?

In cardiovascular vessels; red cells stain pink and white cells stain purple.

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Blood

What identifies lymph?

Lymphocytes in a fluid matrix with small amounts of dissolved protein in lymphatic vessels.

What are the characteristics of muscle tissue?

Long, slender cells with actin and myosin; excitable and contractile.

What is the function of muscle tissue?

Moves skeletal elements and material within hollow organs.

What identifies skeletal muscle?

Long, multinucleate cells with obvious striations and nuclei flattened at the edges.

Where is skeletal muscle found, and how is it controlled?

In skeletal muscles; produces voluntary movement.

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Skeletal muscle

What identifies smooth muscle?

Spindle-shaped cells with one central nucleus and no visible striations.

Where is smooth muscle found, and what does it do?

In organ and vessel walls; involuntarily propels substances through passageways.

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Smooth muscle

What identifies cardiac muscle?

Striated, branched, uninucleate cells.

Where is cardiac muscle found, and what are intercalated discs?

Only in the heart; intercalated discs are junctions between cells.

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Cardiac muscle

What two broad cell categories compose nervous tissue?

Neurons and glia, also called neuroglia.

What are the roles of neurons and glia?

Neurons are excitable functional cells; glia support the nervous system.

What is the function of nervous tissue?

Fast integration and communication between body systems.

Where is nervous tissue found?

Brain, spinal cord, and peripheral collections of cell bodies called ganglia.

What features identify nervous tissue on the listed slide?

Large triangular neuronal bodies, tangled projections, and small purple glial nuclei.

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Nervous tissue