ANATOMY AND PHYSIOLOGY ITissue Types

Key Terms• Histology:

• the study of tissues.

• Tissues:

• groups of cells which are similar in structure and which perform common or related functions.

Four Basic Kinds of Tissues

•Epithelial Tissue•Connective Tissue•Muscle Tissue•Nervous Tissue

Epithelial Tissue• Epithelial Tissue Locations:

• Covers the body• Lines the cavities, tubes, ducts and blood vessels

inside the body• Covers the organs inside body cavities

• Epithelial Tissue Functions:• Protection from physical & chemical injury,• Protection against microbial invasion,• Contains receptors which respond to stimuli,• Filters, secretes & reabsorbs materials and• Secretes serous fluids to lubricate structures.

Connective Tissue• Connective Tissue:

• Most abundant & widely distributed tissue

• Connective Tissue Functions:• Connects, binds and supports structures,

• Tendons, ligaments, etc.

• Protects & cushions organs and tissues,• Insulates (fat) and• Transports substances (blood).

Muscle Tissue• Muscle Tissue:

• Associated with the bones of the skeleton, the heart and in the walls of the hollow organs of the body.

• Muscle Tissue Functions:• Movement• Locomotion• Maintains posture• Produces heat• Facial expressions• Pumps blood• Peristalsis

Nervous Tissue

• Nervous Tissue:• Main component of the nervous system,

ie., brain, spinal cord & nerves.

• Nervous Tissue Functions:• Regulates & controls body functions• Generates & transmits nerve impulses • Supports, insulates and protects impulse generating neurons.

• Specific tissue types & representative cell types we will review:

• epithelial• Squamous• Cuboidal• Columnar

• connective• Adipose• Bone• Hyalaine cartilage

• muscle• Skeletal• Cardiac• smooth

• nervous

Squamous Epithelium

• Simple – one cell thick

Forms solid layer of cells which line blood vessels, body cavities & cover organs in body cavities

Stratified – multiple Stratified – multiple layerslayers Forms epidermis

Cuboidal Epithelium

• Simple – one cell thick• Roughly cube shaped

Line ducts in kidneys, etc, where reabsorption and secretory activities take place.

Duct

Cuboid Cells

Duct

Cuboid Cells

Columnar Epithelium

• Simple – one cell thick• Column shaped (long & narrow)

• Line digestive tract where reabsorption & secretion occurs.

Pseudostratified – Pseudostratified – gives the gives the appearance of appearance of more than one more than one layer of columnar layer of columnar epithelial cellsepithelial cells

• Specific Connective Tissue Types:

• Adipose• Bone• Hyalaine cartilage

Connective - Adipose

• Honeycomb or chickenwire appearance

Stores energy (fat)Stores energy (fat) InsulatesInsulates Supports & protects Supports & protects

organsorgans

Connective - Bone

• Tree ring-like appearance

Supports & protects Supports & protects Mineral storageMineral storage Fat storageFat storage Blood cell Blood cell

productionproduction

Connective – Hyaline Cartilage

Supports while Supports while providing flexibilityproviding flexibility

Absorbs Absorbs compression compression between bones in between bones in joints (articular joints (articular cartilage)cartilage)

Holds open Holds open respiratory respiratory passages passages

Most abundant type Most abundant type of cartilage in bodyof cartilage in body

• Specific Muscle Tissue Types:• muscle (skeletal)

Muscle - Skeletal• Muscle fibers (cells) long, parallel & cylindrical

• With many nuclei (multinucleate)

Striations (cross Striations (cross stripes run stripes run perpendicular to perpendicular to the cellsthe cells

Produce voluntary Produce voluntary movementmovement

LocomotionLocomotion HeatHeat

Specific Nervous Tissue Types Nervous – Neuron

Branching cells with Branching cells with many long many long processesprocesses

Large central Large central nucleusnucleus

Transmit impulses Transmit impulses from one area of from one area of the body to other the body to other areasareas

Regulate activities Regulate activities through neuron through neuron impulsesimpulses