exam 3 quiz 2 Histology

Malignant epithelia tumor

Carcinoma

Epithelial tissues produce what

Cytokeratin filaments are part of cytoskeleton (useful for IHC to diagnose carcinoma)

Functions of epithelium (PEAS R functional)

Protection, excretion, absorption, secretion, regulation of molecule exchange

Simple vs stratified

Simple- 1 layer, stratified- 2+ layers (named for apical layer)

3 epithelial cell shapes

Squamous: scales/ fried egg

Cuboidal: cube

Columnar: taller than wide

Simple squamous epithelium (2 types)

Mesothelium: lines body cavities (lubricating)

Endothelium: lines blood and lymphatic vessels and heart

Simple cuboidal epithelium

Lines ducts and tubules (kidneys)

Simple columnar epithelium

Line secretory and absorptive surfaces + ducts (stomach, intestines, gallbladder)

Transitional epithelium

URINARY TRACT cobblestone appearance, accommodate stretch + acidity (transition btwn cuboidal and squamous)

Transitional nondistended state

4-5 layers thick, puffy bulge into lumen

Transitional distended state

2-3 layers thick, flattened surface layer

Stratified squamous epithelium

Basal layer is cuboidal, apical layer is squamous PROTECTIVE (skin, oral cavity, esophagus, cervix, vagina)

Pseudostratified columnar epithelium

RESPIRATORY TRACT appears stratified, actually simple, goblet cells

Basal surfaces

Basement membrane and hemidesmosomes

Lateral surfaces (intercellular)

Cell junctions

Apical surfaces (luminal)

Microvilli (GI) , sterocilia (repro) , cilia (movement)

Basement membrane characteristics

Carb rich, PAS-positive, 2 layers

2 layers of basement membrane

Basal lamina (top) and reticular lamina (bottom)

What do hemidesmosomes connect

Epithelial cells and basal lamina

Bullous pemphigoid

Form anti-hemidesmosome Abs, blister separates basal cell layer

Kartagener syndrome

Primary ciliary dyskinesia with situs invertus and infertility

What do desmisomes link

Adjacent cells to each other

What moves cilia

Dynein arms

What makes ECM

Fibroblasts

Function of ground substance

Allows compression

What does collagen provide

Tensile strength

Loose areolar connective tissue

Packing material

Dense irregular connective tissue

Stress from many directions

Dense regular connective tissue

Parallel bundles, Tendons and ligaments

Chondroblasts

Build cartilage

Where do chondrocytes sit

In lacuna

Appositional growth

Add cartilage to outside → Perichondrium

Interstitial growth

Add cartilage to inside → Chondrocyte mitosis

Hyaline

Trachea

Elastic cartilage

Ears, epiglottis

Where is fibrocartilage found

Intervertebral discs, menisci, pubic symphysis

Osteablasts

Build bone, secrete osteoid, crystals

Osteocytes

Maintain bones

Osteoclasts

Bone resorption, multinucleated cell in Howship lacuna

Osteon

Circles on circles → Concentric lamellae and Haversian canal

What connects osteons

Volkmann canals

Osteopetrosis

Defective osteoclasts

Pagets disease

Overactive osteoclasts

Intramembranous growth

Flat bones

Endochondral growth

Long bones

Growth plate order

1. Proliferation

2. Hypertrophy

3. Calcification

4. Ossification

Articular hyaline cartilage

Covers ends of bones in synovial joints

Why does cartilage heal poorly

It’s avascular and has no perichondrium

Reticular fibers

Type 3 collagen, best seen with silver stain

How are chondrocytes found in fibroblasts

In stacks/rows (type 1 collagen bundles)

What is basic functional unit of compact (cortical) bone

Osteon

White adipose tissue

Energy storage, unilocular pushes nucleus to outside

Brown adipose tissue

Generate heat by nonshivering thermogenesis

What is a lacuna

A small space that houses a mature cell (chondrocytes, osteocytes)

Where are Nissl bodies found

In soma of neurons

What is in a Nissl body

Rough ER and ribosomes

What do Nissl bodies do

Protein synthesis

Unipolar neurons

Sensory ganglia

Bipolar neurons

Special senses

Multipolar neuron

Most neurons

Where are neurotransmitter vesicles found

Presynaptic region

Which region has proteins that bind NT and create electrical impulses

Post synaptic region

Where are Schwann cells found

PNS

Function of Schwann cells

myelinates axons in PNS one at a time and Help regeneration after injury

Where are oligodendrocytes found

CNS

Where are oligodendrocytes found

CNS

Purpose of myelin

Insulation and faster conduction

What is node of ranvier

Gap between myelinating cells

Function of nodes of ranvier

Saltatory conduction (action potential jumps)

what are astrocytes

CNS Glia, support cells

Function of astrocytes

BBB support and CNS scar formation after injury

Location of astrocytes

Protoplasmic: gray matter

Fibrous: white matter

Microglia

Macrophages of CNS

Ependymal cells

Line CNS ventricles

Where are Nissl Cells absent

Axon and axon hillock

Collection of cell bodies in PNS and CNS

PNS: ganglion

CNS: nucleus

Merkel cell

Intra-epidermal touch receptor