Microanatomy TA Session 1

Mitochondria

ATP production and apoptosis

Rough ER

Protein synthesis, ribosomes attached

Golgi Apparatus

Protein packaging, prominent in secretory cells

Lysosomes

Intracellular digestion, contains hydrolytic enzymes

Proteasomes

Destroy damaged proteins, requires ubiquitin

Peroxisomes

Detoxification, contains catalase

Euchromatin

Pale/light staining, ACTIVE DNA

Heterochromtin

Dark/dense staining, inactive DNA

Light Microscope Resolution

0.2 micrometers

TEM Resolution

0.16-0.18 nanometers

TEM Image

2D internal structures

SEM Image

3D surface structures

Bright field microscopy requires

Staining

Fluorescence microscopy uses

UV light

Hematoxylin

Color - blue/purple

Stains - DNA, RN

Basophilic structures

Eosin

Color - pink

Stains - proteins/cytoplasm

Eosinophilic structures

H&E

Color - Blue/pink

Stains - routine tissue stain

Most common

PAS (Periodic Acid-Schiff)

Color - magenta

Stains - glycogen, mucins, glycoproteins

Goblet cell positive

Masson’s Trichrome

Color - Blue collagen

Stains - Connective tissue

Collagen stains blue

Perls Prussian Blue

Color - blue

Stains - iron/hemosiderin

Identifies iron pigment

Gomori’s Method

Color - black

Stains - alkaline phosphatase

Kidney brush border

Immunohistohemistry

Color - variable

Stains - specific antigens

Antibody-based

Fluorescent Stains

Color - Fluorescent colors

Stains - DNA/proteins

UV microscopy

Microfilaments

Function - Movement/shape

Main protein - Actin & myosin

Intermediate Filaments

Function - Structural support

Main protein - Tissue-support

Microtubules

Function - Transport/cilia

Main protein - Tubulin

Cytokeratin Tissue Type

Epithelium

Vimentin Tissue Type

Connective tissue

Desmin Tissue Type

Muscle

Neurofilaments Tissue Type

Neurons

Microvilli

Brush border of the intestine, non-motile

Stereocilia

Large microvilli in epididymis, non-motile

Cilia

Ciliated cells in respiratory tract, motile

Hemosiderin

Iron storage

Melanin

UV Protection

Lipofuscin

Wear-and-tear pigment

Lipid

Energy storage

Glycogen

Glucose storage