MMS Histology
Virtual Laboratory - Fall 2020
Directives:
1. Examine the virtual microscope slides on the LUMEN website:
a. http://www.meddean.luc.edu/lumen/MedEd/Histo/virtualhistology.htm
b. Please note that each slide can be scanned and zoomed – see Image Navigation Help.
c. You will need to examine each slide under both low (-) and high power (+) to identify all structures for
which you are responsible.
2. Most slides on the LUMEN site include a “Show description” which provides a brief description and/or guide to
the section.
3. It is recommended that you study additional virtual specimens using the links below:
a. http://www.histologyguide.com/slidebox/slidebox.html ****(very good resource)
b. http://141.214.65.171/Histology/Basic%20Tissues/view.apml
4. For each slide:
a. Identify the organ and tissues present, cell types, connective tissue and character of the extracellular
matrix.
b. Correlate structure of cells/tissue with function.
5. Use your class notes and text book to work through the sections. The Atlas part of each chapter will be
especially helpful.
October 14, 2020
Lab 1: Epithelium, Connective Tissue Proper, Blood
Objectives:
1. Examine the slides listed below. Classify all epithelium and identify types of connective tissue. Identify cell types
and connective tissue fibers/extracellular matrix where appropriate.
a. Epithelium - http://zoomify.lumc.edu/epithelium/epithelium_main.htm
Trachea #98
What type of epithelium lines the trachea?
• Pseudostratified ciliated columnar epithelium (cilia – motility)
Identify the different cell types.
• LCT, DRCT, fibroblasts, basement membrane (thick in trachea)
• Scattered goblet cells (secret mucus) and plasma cells
Zoom in (+) to identify microvilli and cilia.
Salivary Gland #117 and #118
#117
#118
What type of epithelium lines the duct system?
• Simple cuboidal – both
What types of secretions are made by these glands?
• Mix of mucous (sublingual – low water content) and serous (parotid – high
water content), as well as serous demilunes (caps - submandibular) – both
What type of glands are present?
• Compound tubuloacinar – both
Esophagus #120
What type of epithelium lines the esophagus?
• Stratified squamous
Do all epithelial cells exhibit the same morphology?
• No! The most superficial cells still contain visible, albeit, pyknotic nuclei and
may retain some viability prior to their sloughing
• Look more cuboidal as you go down the epithelium
What type of glands are present?
• Simple branched tubular
Jejunum #130
What type of epithelium lines the jejunum?
• Simple columnar
Identify microvilli and villi
• Microvilli – absorption
What type of glands are present?
• Simple tubular
a. Identify a goblet cell (first picture)
Be sure to examine the epithelium at the base of the glands.
Goblet cell
Mesentery DMS030
The mesentery is composed of what type of epithelium?
• Simple squamous (pic from lab wasn’t great so I found another)
Ureter #157
What type of epithelium lines the ureter?
• Transitional (dome/umbrella cells)
How does this particular epithelium change with alterations in volume?
• Specialized for distension – cells flatten and “unfold”
Thyroid #195
What type of epithelium lines the thyroid follicles?
• Simple cuboidal
What type of gland is this?
• Endocrine (ductless) – glands that synthesize and secrete products, called
hormones (thyroid hormone here), directly into the blood rather than
through a duct
b. Skin and Oral Cavity - http://zoomify.lumc.edu/skin/skin_main.htm
i. Lip Sagittal #112
What are the two types of lining epithelium?
• Keratinized (outer) and non-keratinized (inner) stratified squamous
epithelium
What glands are present?
•
Simple coiled tubular
c. Connective Tissue Proper - http://zoomify.lumc.edu/connective/connective_main.htm
i. Mesenchyme DMS051
Zoom in. Identify the features of mesenchyme.
• Embryonic CT, undifferentiated CT, very cellular, sparse collagen and
reticular fibers, high nuclear to cytoplasmic ratio, contains developing
collagen
ii. Areolar CT #12
Zoom in. What types of cells and CT fibers are present?
• Loose CT
• (purple) elastic fibers and (pale pink) collagen fibers
• Relatively cellular (many “wandering” cells) with thin, sparse fibers
• Abundant ground substance– site of inflammatory/immune response,
ideal for diffusion
iii. Tendon #16
Zoom in. What types of cells and CT fibers are present?
•
Dense regular CT, fibroblasts present, collagen bundles in parallel
iv. Ileum #131
Zoom in. What types of cells and CT fibers are present?
•
Simple columnar epithelium w/ microvilli (absorption)
Dense irregular CT (fibroblasts, collagen bundles)
White
adipose
tissue
v. Colon #135
Dense regular CT (fibroblasts, collagen bundles)
LCT under
basement
membrane
What type of connective tissue is present?
•
Dense regular CT and LCT
• LCT
What CT cells can be found?
• Fibroblasts, collagen, plasma cells, goblet cells, some eosinophils
Also note: simple columnar epithelium and simple tubular glands
d. Blood and Capillaries - http://zoomify.lumc.edu/blood/blood_main.htm
i. Blood smear – Wright stain DMS101 (see description!)
What properties warrant the classification of blood as a “connective tissue”?
•
•
Platelet
(thrombocyte)
Has ECM and different cell types; it’s a fluid CT
Cells: RBCs (erythrocytes – 45%), WBCs – leukocytes (agranulocytes
and granulocytes – WBC w/ secretory granules in cytoplasm – i.e.
neutrophil, basophil, or eosinophil), and platelets (thrombocytes)
What composes the matrix?
• Plasma: liquid extracellular material that gives fluid properties to
blood. Volume of cells and plasma in blood is 45-55%
Zoom and scan for leukocytes. Identify them. What histological features distinguish the
different types of leukocytes?
RBC
(erythrocyte)
Eosinophil
Neutrophil
Monocyte
Lymphocyte
(small)
Lymphocyte (large - activated)
Basophil
ii. See slide 63X @
http://virtualslides.med.umich.edu/histology/Cardiovascular%20System/Hematology%20Lab%2
0Normal1%2063X.svs/view.apml?X=0&Y=0&zoom=4.77038310412574
October 27, 2020
Lab 2: Bone and Cartilage
Objectives:
1. Examine the slides listed below. Identify and classify all tissues, cell types and structures.
a. Bone and Cartilage - http://zoomify.lumc.edu/bone/bone_main.htm
i. Elastic cartilage #19, External Ear DMS056
Find the cartilage. What features designate it as “elastic” cartilage?
Elastic cartilage is like hyaline cartilage except that the matrix also contains a dense
network of branching and anastomosing elastic fibers. It provide support and is present
in the outer ear and epiglottis. When stained with H&E, the elastic fibers are unstained.
Elastic cartilage is in extracellular matrix and does not calcify. The perichondrium is a
layer of dense irregular connective tissue that surrounds the cartilage. It is divided into 2
layers:
1) Outer fibrous layer-fibroblasts that produce the type I collagen on the outer surface of
the perichondrium
2) the inner chondrogenic layer-contains mesenchymal cells that differentiate into
chondroblasts, initiate matrix production (elastin and type II collagen) and become
immature chondrocytes.
What cell type is present in the cartilage?
Chondrocytes- cells within lacunae inside the cartilage that occurs singularly or in clusters
called isogenous groups
What type of epithelium is on the outside? What other CT is present?
Fibroblasts produce the type I collagen on the outer surface of the perichondrium. The
perichondrium is the layer of dense irregular CT
ii. Pubic Symphysis DMS066, Fibro-cartilage #20
Identify the cartilage. Compare and contrast to elastic and hyaline cartilage.
Made of hyaline cartilage and fibrocartilage.
x
Identify an isogenous group.
What other locations in the human body can you find fibrocartilage?
iii. Trachea – transverse section LU095, Larynx DMS065
What type of cartilage is present?
Tracheal cartilage & hyaline cartilage which is “C”-shaped (have chondrocytes)
Hyaline cartilage
Review the epithelium and glands.
Respiratory epithelium- the trachea is lined with. Pseudostratified columnar epithelium
with cilia and goblet cells (secrete mucus).
Have sero-mucous glands that add moisture to air and aid in trapping contaminants. The
cilia propel mucus towards the esophagus where it is swallowed.
Sero-mucous glands
iv. Bone #22, Bone #23
Identify the periosteum, endosteum and bone marrow.
Outer surface: the periosteum covers the outside surface of all bones and consists of
dense irregular connective tissue with collagen type I and fibroblasts (outer fibrous layer
(pink, only fibroblasts), inner cellular layer (purple nuclei, osteoblasts, fibroblasts) ),
periosteal cells, Sharpey’s fibers
Inner surface: endosteum (osteoblasts, osteoclasts), endosteal cells, bone marrow
Osteoblasts are cuboidal-columnar and are flattened with inactive- they make bone!
Osteoclasts are giant multinucleated cells
What cell types are present?
Osteoprogenitor cellsdifferentiate into osteoblasts and can also form chondroblasts,
adipocytes, and fibroblasts
Dense irregular connective tissue
v. Ground Bone #24
Identify an osteon, Haversian canal and the lamellae (interstitial, outer and inner
circumferential).
What cell type lines the Haversian canals?
osteoblasts
Identify an osteocyte.
vi. Developing long bone DMS072
Identify all component features.
Identify the endosteum and periosteum.
vii. Endochondral Ossification - Fetal Finger #26, Ossification DMS068
Identify all cartilaginous and bony regions and all zones of epiphyseal cartilage.
Find newly formed bone.
What type of cartilage is present?
Find perichondrium.
November 3, 2020
Lab 3: Muscle and Nerve
Objectives:
1. Examine the slides listed below. Identify and classify all tissues, cell types and structures.
a. Muscle - http://zoomify.lumc.edu/muscle/muscle_main.htm
i. Skeletal Muscle #46, #48, DMS076, DMS078
Be able to distinguish skeletal muscle from dense regular CT and peripheral nerve.
Zoom in to identify Z lines, etc.
ii. Heart #50, #54, DMS082
Identify the features that characterize this as cardiac muscle.
iii. Smooth Muscle – Ileum #131
Distinguish smooth muscle from dense irregular CT and peripheral nerve.
b. Nerve - http://zoomify.lumc.edu/neuro/neuro_main.htm
i. Peripheral Nerve #57, #58, #60, DMS094 and DMS095
Identify the CT layers associated with peripheral nerve. Also, identify axons and myelin
sheaths. Compare and contrast to dense regular CT, skeletal muscle and smooth muscle.
ii. Dorsal root #62 + Spinal cord #75
Examine the gray and white matter of the spinal cord and dorsal root ganglion.
What cell types are present in the dorsal root ganglion?
iii. Spinal cord #76, DMS092
Zoom in to find neuronal cell bodies and primary dendrites.
Identify Nissl substance, the cell nucleus and the nucleolus.
Identify other cell types that are present.
iv. Sympathetic ganglion #64, DMS093
Compare and contrast to dorsal root ganglion.
What neuronal cell types are present?