Microscopic Anatomy Of Tissues Part 1

Part 1

What are cells

• smallest ?

• capable of?

• Group together to form?

1. structural unit of living matter

2. Functioning independently

3. Form a TISSUE

Four types: CELLS?

• Epithelial

 Connective

 Nerve

 Muscle

Tissue:

• Group of _____ cells that would perform a similar within ___?

Group of interconnected cells that perform a similar function within an organism

Tissues and organs composed of?

Several different types of cells and extracellular elements

Extracellular Matrix IS WHAT?

• Insoluble 3d structural of___ that physically____ the?

• Provides a____ _____within cells move and ____ and ____ them together

• scaffold(building), supports the cells

• Provides a biomechanical framework within which cells move and interact and holds them together

  Ex: ( structure like building holding together- floors that all of em work together)

Extracellular Composed of, Types of Extracellular:

• Ground substance like ( gel like- SLIME)

• Facilitates attachment of cells to the matrix

• Aids in the exchange of nutrients between cells and capillaries

• Fibrous Proteins, needing fiber and protein to poop

Types of EXtracellular:

Minimal Epithelial tissue, Greater Connective tissue.

Development review:

• 7th week, the outer part of the ectoderm gives rise to

the oral epithelium

The oral epithelium originates from what of?

two horseshoe-shaped bands of tissue at the surface of the stomodeum, will become each arch (maxillary and mandibular).

Microscopic ANATOMY of Epithelial Tissue?

Outer covering of the body (skin, epidermis)

Lines body cavities (mouth, stomach, and intestines (mucosa))

Composition of

• Stratified (several cell layers)

• Squamous (flat cells) Epithelium—> Flat cells arranged in layers”

Types of Epithelial Tissue ( 3)

Simple Epithelium

• Alveoli (lungs), blood vessels (endothelium), serous membranes, kidney tubules, glandular ducts, digestive tract lining, uterus

• Stratified Epithelium

  • Skin (keratinized), oral cavity, esophagus, vagina (nonkeratinized), large ducts of glands (e.g., salivary, sweat glands)

• Dental tissues: enamel

Composition of Epithelial Tissue: MAIN types

Plentiful?

• Cells supported by a thin mat of extracellular matrix

• Closely packed epithelial cells bound together into sheets

 Sparse Extracellular Matrix

• Minor component existing in the basal lamina

• Thin mat secreted by epithelial cells

• Supports overlying epithelium (foundation)

• Functions like a filter

Composition of Epithelial Tissue

 Keratinized layer: No nuclei

 Nonkeratinized layer: Nuclei

 Basal cell layer

 Basal lamina

 Blood vessel

What is Keratinization?

• Tough, resistant layer, process by which epithelial cells on the skin’s surface become stronger and waterproof.

• Keratinized epithelial cells have no nuclei.

Nonkeratinized Epithelial Cells? Found in? Function?

Have a nuclei, Act as a cushion against mechanical stress and wear

• Softer and more flexible

Found in mucosal lining

• i.e. Cheeks,

  FUNCTION: Allows for mobility to speak, chew and make facial expressions

What is the Blood Supply of Epithelial Cells ?

Avascular

• No Blood vessels

  Receives oxygen and nourishment from blood vessels located in the connective tissue, diffusion

What are the 4 Tying into the Gingiva?

• Keratinized Layer

• Nonkeratinized Layer

• Basal Cell Layer

• Basal Lamina

What is the Epithelial Cell Junctions? FUNCTION?

Mechanically lock a cell and its cytoskeleton to its neighboring cells or basal lamina:

FUNCTION

• Bind cells together as a strong structural unit

• Tissues such as epithelium of skin have the most abundant number of cell Junctions

• Can withstand severe mechanical stresses

What are the 2 TYPES OF Epithelial Cell Junctions

1-Desmosome,

2- Hemidesmosome

What is Desmosome? Found in?

Desmosome?

• Create cell-to-cell connections

Found in:

• Important form of cell junction found in gingival epithelium

Hemidesmosome

Create cell-to-basal lamina connection  Important form of cell junction found in gingival epithelium

Moving into the Connective Tissue,

Where is the connective tissue located in the gingiva?

Near the light pink area of the image from slides, under the base of sulcus - junctional epithelium

Composition of Connective Tissue( 2)

Basal lamina- this is under the basal cell layer(line above) and the basal LAMIN is the under line

Blood vessels: blood supply is network of arteries (tube) through which the blood circulates.

Lamina Propria loose and filler btw? Supports and?

aka connective tissue

• Filler between tissues and organs

• Supports and binds other tissues

Lamina Propria Cells are? Surrounded by?

Sparsely distributed

An abundant extracellular substance (gel-like)

Lamina Propria are the network of?

Network of strong fibers

Microscopic anatomy CT (lamina propria):

What are all specialized in connective tissue?

Cementum, dentin, alveolar bone, and pulp

What are the types of Connective Tissue?

• Loose connective tissue

• Ligaments and Tendons

• Cartilage, Bone

• Bone marrow, Blood

• Tonsils and lymph nodes , Fat (adipose)

• Dental tissues: cementum, dentin, pulp

Extracellular matrix of CT—>(Lamina Propria):

Ground Substances are rich “____” contain strong____

gel-like substance containing strong fibers that hold the cells together.

Extracellular matrix of CT—>(Lamina Propria):

Fiber Matrix Provides strength against?

Mechanical forces

Extracellular matrix of CT—>(Lamina Propria):

Protein Fibers: TYPES?

Collagen—> (does not stretch) , Elastin—→ (rubber band)

Collagen non elastic fibers that are?

Elastin: elastic fibers that____

• Collagen—>resistant to tension

• Elastin—> stretch and return to original length

Extracellular Matrix of Connective Tissue(lamina propia)

3 Types of Cells?

Fibroblasts

Macrophages and Neutrophilis phagocytes

Lymphocytes

Fibroblasts(fiber builders) secrete into the?

Comprised of ?

Fibroblasts-

• intercellular spaces

• Fibers and ground substance (extracellular matrix)

Macrophages and neutrophils phagocytes are ?

What do they devour and invade?

Cell eaters, that devour dying cells and invading microorganisms

Lymphocytes are the and host for?

immune cells for host defense

Epithelial-Connective Tissue Interface:

• What are the two types of interface?

• Basal Lamina

• Basement Membrane

Basal Lamina, thin layer secreted by?

• Where does it sit on?

• Is it visible?

• Facilitates attachment of

By epithelial cells on which the epithelium sits

• Not visible

• Facilitates attachment of epithelial cells to adjacent structures

Basement Membrane, thin layer of tissue that is ?

• From the?

• Formed by a combination of?

• Visible or not?

Beneath the epithelium

• Connective tissue

• basal lamina and a reticular lamina

• Visible under the microscope

Epithelial C.T—> Interface

Site where?

Interface is ?

Type of Boundaries (2)?

Epithelial and connective tissues meet

• Interface = Boundary

Type of Boundary

• Wavy

• Smooth

Morphological Patterns Epitheilal C.T INTERFACE

• Wavy interdigitation is? even or not? interlocked or non? common or not?

Wavy interdigitation:

• Tight Interdigitation

• Wavy, uneven

• Interlocked fingers

• Most Common

Which boundary is stronger or better?

• Wavy or Smooth?

Wavy is stronger because it is tight interdigitation and interlocked fingers, It would not break here: it is like your fingers together like holding hands with someone!

Smooth is the non?

• Not even or Even?

• has no epithelial____ or connective tissue of

• Healthy ____epithelium and healthy _____

Smooth, Non-interdigitating

• Even, smooth

• No epithelial ridges or connective tissue papillae

 Healthy sulcular epithelium and healthy junctional epithelium

E.C-T (3): Wavy–TYPES

Epithelial ridges:

Connective tissue papillae

Gingival Stippling

1. Epithelial ridges –

• Deep extensions of the?

• Extend into the C-T which is called?

• epithelium

• (rete pegs) arrow goes down —>

2. Finger-like

   • extensions that project____ and inter__ with the ?

• Project up and interlock with the epithelium

3. Gingival Stippling

   • Presence of_____ corresponds to? Of ?

• rete pegs

• microscopic elevations and depressions

• epithelial-connective tissue interface

Functions of Wavy Epithelial –

• Adds protection from the and due to?

• Better adhesiom by ?

• More opportunity for and from?

Connective Tissue Boundary

• physical shearing forces due to increasing the surface area

• increasing surface area

• Nourishment from connective tissue