Histology: Connective Tissue Lab
Name____________________________________
Hour ______
Looking at the picture as a guide, find each type of muscle on a prepared microscope slide and have your teacher
sign off on each. Then write the general description, function, and location of each type.
Loose Connective -Adipose
Description
Function
Location
Loose Connective - Areolar
Description
Function
Location
Cartilage - Hyaline
Description
Function
Location
Cartilage - Elastic
Description
Function
Location
Dense Connective – White fibrous or tendon
Description
Function
Location
Dense Connective – Irregular (skin slide)
Description
Function
Location
Bone - Compact
Description
Function
Location
Bone - Spongy
Description
Function
Location
Blood (show all cell types in one drawing)
Description
Function
Location
Connective Tissue Slide Descriptions:
Slide 1: Loose Connective - Adipose Tissue
The cells of adipose tissue (adipocytes) possess a large vacuole for the storage of lipids or fats. This gives the
tissue an open or lacy appearance. The red “bands” running through the tissue is fibrous connective tissue for
support. Adipose tissue provides padding, insulation, shock absorption, and long term storage of energy. Most
adipose tissue is called white fat because of its pale, yellow-white color.
Adipose connective tissue 400X
Slide 2: Loose Connective – Areolar
Found on a separate areolar slide or under the skin layer on the skin slide
This tissue is the least specialized connective tissue is adults. It may contain all the cells and fibers of any
connective tissue in a very loosely organized array. Areolar tissue has an open framework. It forms a layer that
separates the skin from the underlying structures. In addition, it provides padding, the elastic properties of the
layer allows a considerable amount of movement.
Areolar connective tissue 400X
Slide 3: Hyaline Cartilage
There are three type of cartilage (hyaline, elastic, and fibrocartilage) depending on the kind and the amount of
fibers found in the “gel” matrix of the tissue. This slide contains hyaline cartilage which lacks fibers in its matrix.
The stain used in the slide preparation has colored the cartilage purple. The cartilage cells (chondrocytes) are
found in the clear opening (lacuna) in the “gel” matrix. This cartilage is found between the ribs and sternum, the
nose, the passageways of the lungs, and opposing bone surfaces in many joints.
Hyaline cartilage 400X
Slide 4: Cartilage – elastic
This slide contains elastic cartilage that has numerous elastic fibers embedded in the background matrix. These
fibers make this type of cartilage extremely resilient and flexible. This elastic cartilage forms the outer ear, the
epiglottis, the auditory tube, and the small cartilages of the larynx.
Elastic connective tissue 400X
Human aorta c.s
The labels indicate individual
elastin fibers (ef) in the aorta.
The areas stained pink (between
the elastin fibers) contain
smooth muscle cells, reticular
fibers, and ground substance.
Slide 5: Dense Connective – White fibrous or Tendon
Tendons attach muscle and bone. This “teased” tissue has been torn apart to show the protein fibers (collagen)
which run parallel to each other and are embedded in the matrix. Ligaments are similar in structure but attach
bone to bone. The tissue cells appear as small black bodies scattered among the fibers. These cells are called
fibroblasts. They contain large numbers of rough “er” because they produce the collagen fibers.
Dense regular connective tissue 400X
Tendon
In this image a fibroblast
nucleus (fb nuc) is labeled, but
you can see other nuclei once
you know what to look for. You
can't see the rest of the fibroblast
cell because it stains the same
color as the collagen fibers. The
collagen fibers (cf) are parallel
to the arrow bar. It's hard to see
on the image, but the collagen
fibers are not really straight.
They have a slight "wave".
The "art" label indicates an artifact--a place where the collagen fibers pulled apart
slightly during processing. Don't confuse the artifacts with real structures.
Slide 6: Dense Connective – Irregular (skin slide)
In contrast to the tendon slide, the fibers in dense irregular connective tissue form an interwoven meshwork in no
consistent pattern. These tissues strengthen and support areas subject to stresses in many directions. A layer of
dense irregular gives skin its strength . It is also found around cartilage, bone, and it surrounds the liver, kidneys,
spleen, and cavities of joints.
Stratified Squamous (skin)
 Dense Connective (irregular)
Slide 7: Bone – Compact – Calcified and Decalcified (femur
c.s.)
Compact bone is found in the shafts of long bones. The intercellular matrix is made of hard Calcium phosphate,
Ca3(PO4)2 which is almost impossible to view through a microscope.
This slide is a cross-section of a hollow long bone. Do not confuse bone cells (osteocytes) with the opening in the
bone (Haversion canals and canaliculi) which contain blood vessels and nerves.
Bone, compact, ground c.s., thin-section
400X
A lamina (lam) is a layer of
matrix between two concentric
"rows" of osteocytes. It is
difficult to know where one
lamina begins and ends, because
the osteocytes are not arranged
in neat rows. The number of
rows is limited by the distance
nutrients can diffuse from the
blood vessel in the central canal
to the osteocytes. The outermost
osteocytes can't be more than
about 0.2 mm from the central canal.
Bone, compact, decalcified c.s.
400X
Osteocytes (o) in lacunae show
up as dark spots. Sometimes you
can see a sliver of white space
around the osteocytes. The larger
open areas in the bone are canals
carrying capillaries (cap) and
nerves. This is an enlargement
from the left side of the image
above. The compact bone tissue
on the outside of a bone is often
made in layers (circumferential
lamellae) that extend around the
bone instead of being part of an osteon. Tissue from the outside of a bone is more
difficult to recognize because you can't see the osteons.
Slide 8: Bone – Spongy or Cancellous
In this slide of spongy or cancellous bone you will see a more wide open bone structure composed of an open
network of struts and plates. Spongy bone makes up the interior of bones where weight is important such as the
ends of long bones (the epiphysis), flat (pelvis), short (wrist and ankle) and irregular bones (vertebra).
Bone, cancellous, decalcified 100X
The trabeculae (tr) consist of
matrix that is made by
osteoblasts. The bone cells build
a trabecula by adding layers of
matrix on the outside of the
trabecula. This continues until it
runs into another growing
trabecula, and they fuse together.
You can see pale lines in the
trabecula in the center of this
image. The lines are a result of
building up the trabecula layer
by layer. The spaces between the trabecula are filled with active or inactive bone
marrow. Since this bone has adipose tissue in the spaces, the bone marrow in this
area was inactive.
Bone, cancellous, decalcified 400X
The osteocytes (o) of cancellous
or spongy bone are also found in
spaces called lacunae. The layers
of matrix are very clear on this
image.
Slide 9: Blood Human Blood Smear
Blood is only one of many related tissues. This is a thin film of blood called a smear. Locate an area(s) on the
smear where the blood in very thin and locate red blood cells (RBC’s), white blood cells (WBC’s – try to find as
many types as possible), blood platelets. See your text book for more details.
Blood, 100X
Using the 10X objective lens
you can see individual cells and
tell the difference between red
and white blood cells. You can
even see platelets if you know
what to look for. The platelets
on this image are very faint, but
you can see them in the image
below.
Most of the cells you see here
are erythrocytes or red blood
cells. They are small and don't
have a nucleus. They are thin in the middle, and look like red doughnuts in this
image. The leukocytes (white blood cells) are larger than red blood cells and they
have nuclei that stain dark purple. Many of the white blood cells have segmented
nuclei, meaning that the nucleus is pinched into two or more smaller parts that are
still connected to each other (sort of like when you twist one of those long
balloons to make a sculpture). Can you find the white blood cell in this image? Its
nucleus has two segments.