Unit 6

Tissue

Group of similar cells working together for a specific function

Microscopic study of tissues

Histology

4 primary tissue types

Epithelial, connective, muscle, nervous

Function of epithelial tissue

Covers body surface, lines cavities, forms glands

Function of connective tissue

Supports, protects and binds body structures together

Function of muscle tissue

Excitable tissue that contracts to produce movement

Function of nervous tissue

Excitable tissue that transmits nerve impulses

Types of muscle tissue

Skeletal - voluntary muscle attached to bones

Smooth - involuntary muscle found in organs and blood vessels

Cardiac muscle - muscle tissue found only in the heart

What is the main function of epithelial tissue?

Covering and lining body surfaces (internal cavities and passageways) + forms glands

What body systems are lined by epithelium and exposed to the outside world?

Respiratory, digestive, urinary, reproductive system

A type of epithelium lining blood vessels and internal body cavities

Endothelium

Thin membranes covering organs and lining body cavities

Serous membranes

The exposed surface of an epithelial cell

Apical surface

The surface attached to underlying tissue

Basal surface

What does anchor epithelium to connective tissue?

Basal lamina

What forms the basement membrane?

Basal lamina and reticular lamina

Epithelial tissues are… (blood wise)

Avascular

How does epithelium receive nutrients?

Diffusion from underlying tissues

Hair-like projections in the apicial surface

Cilia (moves substances across the cell surface)

Shedding of damages or dead epithelial cells

Sloughing off

What is secretion?

Release of substances from cell

What does the small intestine epithelium secrete?

Digestive enzymes

What do respiratory epithelial cells secrete?

Mucus (traps microorganisms and particles)

What is glandular epithelium?

Epithelium specialized for secretion

What are the 3 basic epithelial cell shapes

Squamous - flattened and thin

Cuboidal - box-shaped, as tall as wide

Columnar - taller than wide

Epithelium with one cell layer, all cells touch the basal lamina

Simple epithelium

Epithelium with multiple cell layer

Stratified epithelium

Also stratified appearance with one cell layer

Psuedostratified

Form of specialized stratified epithelium in which the shape of the cells can vary

Transitional

Simple squamous epithelium - location and function

L: air sacs of lungs and the lining of the heart, blood vessels, and lymphatic vessels

F: allow materials to pass through by diffusion and filtration, secretes lubricating substances

Simple cuboidal epithelium - location and function

L: In ducts and secretory portions of small glands and in kidney tubules

F: Secrets and absorbs

Simple columnar epithelium - location and function

L: ciliated tissues are in bronchi, uterine tubes, and uterus;

Smooth are in the digestive tract, bladder

F: absorbs, secrets mucous and enzymes

Pseudostratified columnar epithelium - location and function

L: Ciliated tissue lines the trachea and much of the upper respiratory tract

F: secreted mucus, ciliated tissue moves mucus

Stratified squamous epithelium - location and function

L: lines the esophagus,mouth, vagina

F: protects against abrasion

Stratified cubodial epithelium - location and function

L: sweat glands, salivary glands, and the mammal glands

F: protective tissue

Stratified columnar epithelium - location and function

L: male urethra and the ducts of some glands

F: secrets and protects

Transitional epithelium - location and function

L: lines the bladder, urethra and ureters

F: allows the urinary organs to expand and stretch

What surrounds connective tissue cells?

Matrix - extracellural material surrounding cells

Main components of connection tissue matrix

Ground substance and protein fibres

What is ground substance?

Amorphous material filling the space between the space between cells and fibres

Functions of connective tissue

Support and connection other tissues (bones, tendons)

Protection

Transport (blood and lymph)

What connect muscles to bones

Tendons (сухожилия)

What is lymph?

Fluid connective tissue involved in transport and immunity

What tissue store fat?

Adipose tissue (жировая ткань)

Main function of adipose tissue

Energy storage and insulation (изоляция - тепло)