IntroductionTISSUE

Vs.

Terminology

epi- -crine macr- erythro- leuko- thrombo- intra- Derm- Histo-

chondro- oss- vas- hyal- sub- pseudo: false, fake stratum: layers

Introduction: Levels of organization

•Seven levels of organization?

•Please write them by INTRODUCTION.

What are tissues?

What are tissues?

• Tissues are cells that are organized into groups and layers.

• All can have different forms, which means… (?)

Four types of tissue:

Types of Tissues

1. Epithelial-covers

2. Connective-connect/support (most abundant)

3. Muscle-movement

4. Nervous-control

Epithelium:

Covers the body, most organs and has a free surface to external and internal spaces.

Characteristics

1. High rate of regeneration

2. Usually avascular (no blood supply)

3. Attached to the basement membrane

Functions

1. Protection

2. Absorption

3. Receive stimuli

4. Form smooth surfaces

5. Secretion: exocrine, endocrine

TYPES

• Epithelial cells are classified by shape and number of layers.

• Squamous, Cubodial, and Columnar

• Simple vs stratified

Types

• Simple: one layer, usually diffusional, ciliated and/or grandular.

1. Squamous

2. Cubodial

3. Columnar

4. Pseudostratified

SIMPLE SQUAMOUS

- Flat thin cell

- Simple (1 layer)- Found:

- Linings of lungs- Inside of blood vessels- Line body cavities

(mouth)- Outer layers of skin.

SIMPLE CUBOIDAL

- Cube shaped cells- Simple (1 layer thick)- Found:

- Lining of ovaries- Kidney tubules- Ducts: (pathways of

glands, sweat glands)

SIMPLE COLUMNAR

- Column shaped- Simple (1 layer)- Ciliated Found:

- Female tubes- Non-Ciliated- Lines the stomach

and intestines.

4. Pseudo stratified : false or fake stratified, looks like more than 1 layer because it has cilia and goblet cells.

• Stratified: more than 1 layer, could be more than 1 kind of shape, it’s named from the top layer.

STRATIFIED SQUAMOUS

– Thick for protection

- Stratified (layered)

- Found:- Skin

- Esophagus

- Oral Cavity

STRATIFIED CUBODIAL

• - Thick for protection

• Stratified (layered)

• Found:

– Mammary glands

– Sweat glands

– Salivary glands

– Pancreas

Stratified Columnar

Usually found on top of cubodial.

Found: Vas deferens, urethra, pharynx

Transitional

- look different upper cells able to change shape.

- Tissues that expand and contract.

- Found in urinary track.

1. Exocrine: secreted onto the surface of the skin and/or digestive track.

Ex. Sweat, enzymes, milk

Grandular: secretes

2. Endocrine: secreted into the surrounding tissues and blood. aka. Hormones (which regulate cells, tissues, organs)

Pseudocrine (ductless goes to blood into capillaries)