Today - Histology

• Banana’s • “learn what the body is

composed of….”• Is this really ANATOMY

1. What type of section is this?2. Where is this section taken (about)?3. Name the membrane layer surrounding organ X.4. Name the space that the arrow is pointing to.5. What is contained within that space?

X

Histology• What histological sections look like

• Epithelial, connective, nervous & muscle tissue– structure, function & location

• Epithelial tissue – simple and stratified

• Connective tissue – fibrous, supportive & fluid– Fibrous: dense & loose– Supportive: cartilage & bone

• Nervous and muscle tissue – brief introduction

What do histological sections look like?

Cells + matrix = tissues

1. Epithelial tissue2. Connective tissue3. Muscle tissue4. Nervous tissue

simple

stratified

Epithelial Tissue

Epithelial cells

Basement membrane

Simple squamous

Simple cuboidal

Simple columnar

Simple epithelial types

Pseudostratified columnar

cilia

Goblet cells

Another simple type……

Stratified squamous - non-keratinized - keratinized (skin)

Transitional (stratified)

Stratified epithelial types

1. Esophagus: food passageway

2. Small intestine: absorption & secretion

3. rectum: passageway for waste

1. Simple or stratified?

2. What type?• Squamous• Cuboidal• Columnar• Pseudo-columnar

Connective Tissue

General Functions:

1. Binds organs2. Support3. Protection4. Immune protection5. Movement6. Storage7. Heat8. Others…..

Three types• Fibrous• Supportive• Fluid

Cells + fibers + ground substance = connective tissue

Cells = fibroblasts

Fibers = collagen & elastin

Cells = fibroblasts

Fibers = collagen

Change composition = change function

loose dense

mesentery

Adipose tissue

Tendons & ligaments

dermis

regular

irregular

Fibrous connective tissue types and function

Supportive connective tissue = cartilage & bone

Cells: chondrocytes Chondro = cartilage

Fibers: collagen or elastin

Ground Substance: firm gel• chondroitin sulfates• proteoglycans

Perichondrium: dense, irregular CT with chondroblasts

hyaline elastic

fibrocartilage

• chondrocytes• collagen & elastin fibers• CS & PG

Cartilage

Cells: osteocytes

Fibers: collagen

Matrix: GAG & mineral saltsGAG = glycosaminoglycans

Bone

Central canal = blood vessel

Surrounded by periosteum

Nervous tissue

Muscle tissue

• neurons & glia• electrical & chemical signals

• muscle fibers• contract when stimulated• skeletal, smooth & cardiac

Mucous membrane:Epithelium, basement membrane, areolar CT, smooth mm)

Membranes line & cover viscera• serous * (ssq, areolar CT, fluid)• mucous * • cutaneous

Putting it all together….

Respiratory epithelium – mucous membrane • simple epithelium with cilia• goblet cells

• Differentiation • Metaplasia

• Neoplasm• Fibrosis

• Weekly review session on Monday’s 5:30 – 6:30 in T-435 HSB with Ben Constance (TA)

• Bone Tissue on Tuesday