exercise 7 ct proper

8/3/2019 Exercise 7 CT Proper

1/11

1

Name: Date:

Year & Section:

Exercise No. 7

The Connective Tissues

I. Objectives:Given a slide of connective tissue, the student should be able to identify the following:

1. Connective tissue cells2. Connective tissue fibers3. Ground Substance4. Blood vessels

II. DiscussionThe Connective or supporting tissues are the packing or the supporting elements of the body.

The morphology of connective tissues is extremely variable but all generally exhibit the following

characteristics:Cells which are few in number.

Intercellular substances which are abundant vary in consistency.

Fibers which may be collagenous, elastic or reticular.

Types of Connective Tissues

I. Connective tissue properII. CartilageIII. BoneIV. Blood

I. CONNECTIVE TISSUE PROPERA. Loose connective tissueB. Dense connective tissue (regular/irregular)C. Connective tissues with special properties

Loose/Areolar Connective Tissue

Type of connective tissue in which the fibers are loosely arranged in an abundant matrix.

Specimen: papillary layer of the skin (teased preparation)

Study the stained section, locating:

Collagenous fibers numerous, thick, wavy and have fibrillar constitution, no free ends

and anastomose.

Elastic fibers finefibers, branching and anastomosing with one another. When cut,

they are extremely flexous

Cells Vary; Fixed Macrophages are irregular in shape with many prolongations;

Fibroblasts are similar to macrophages but differ from them because they have no vacuoles.

The nucleus is prominent; Mast cells are rounded or polyhedral cells full of granules found near

blood vessels; Adipose cells appear as bright spheres varying in size; Eosinophils may be

present with bright unstained granules and lobulated nucleus; Lymphocytes are smaller than

eosinophils having a round nucleus with scarcely visible cytoplasm.


2/11

2

Matrix the abundant interfibrillar and intercellular ground substance. The cells occupy

small spaces, areola, in the matrix.

Draw the fibers and as many of the components as you can observe.

DENSE CONNECTIVE TISSUE

DENSE IRREGULAR CONNECTIVE TISSUE

This refers to the connective tissue in which the irregularly arranged fibers are densely packed in

the ground substance.

Specimen: dermis of the skin


Collagenous fibers come in large bundles cut at different angles. These fibers are

closely interwoven in a random fashion

Elastic fibers few

Cells fibroblasts are less numerous than the loose type. Few polymorphonuclear cellsand lymphocytes can be seen.

Draw a representative section of the field. Label properly.


3/11

3

DENSE REGULAR CONNECTIVE TISSUE

This type of connective tissue shows the regularly arranged fibers which are densely packed in

the ground substance.

Specimen: tendon


Collagenous fibers arranged in compact parallel bundles

Tendon cells Fibroblasts which are found between the bundles of collagenous fibers.

Draw the structures of the entire section. Label properly

CONNECTIVE TISSUES WITH SPECIAL PROPERTIES

EMBRYONIC CONNECTIVE TISSUE

This young form of connective tissue occurs not only in fetal and infantile life but also in

adult during regeneration of destroyed connective tissue areas, dental pulp and some tumors.

Specimen: tunica propia of the uterus

Study and Locate:

Tunica propia found immediately beneath the lining columnar epithelium which is

highly cellular. The connective tissue cells are small, dark staining and mostly fusiform in shape.

Connective tissue fibers are obscured by the coagulated ground substance.

Draw under high power. Label properly.


4/11

4

MUCOUS CONNECTIVE TISSUE

This is a specialized connective tissue, having homogenous, jelly-like material in the

fresh condition.

Specimen: Whartons jelly of the umbilical cord

Study an area of the specimen locating:

Cells Modified fusiform or stellate fibroblasts which have indistinct cell borders

Fibers Numerous, delicate, wavy, collagenous fibers in the matrix

Matrix the translucent mucous substance known as the Whartons jelly.

Draw an area showing the characteristic structures. Label properly

RETICULAR CONNECTIVE TISSUE

This is the type of adult connective tissue which resembles the mesenchyma most

closely.

Specimen: stroma of the lymph glandsStudy and locate

Reticular cells resembles the mesenchymal cells. They are seen clinging to the large

reticular connective tissue fiber network.

Reticular fibers Very fine and arranged in a delicate network. They are seen after

silver staining.

Matrix the abundant intercellular substance in which numerous cells, mainly

lymphocytes are lodged

Draw the characteristic structures of the tissue.


5/11

5

ADIPOSE CONNECTIVE TISSUE

This is a connective tissue in which the cells store excess food material in the form of

fat droplets. The individual droplets coalesce to form the mature signet shaped fat cells.

Specimen: subcutaneous tissues

Study and locate:

Cytoplasm the thin peripheral rim of protoplasm

Nucleus A compressed body which lies in the thickened rom of cytoplasm

Fat vacuole - The fat droplets which have been dissolved by the fixative leaving the

clear vacuole.

Draw the structures seen. Label properly

ELASTIC CONNECTIVE TISSUE

Specialized connective tissue in which elastic fibers predominate. It has a yellow color

macroscopicallySpecimen: fenestrated membranes of large blood vessels

Study and locate:

Elastic fibers the prominent anastomosing bands

Collagenous fibers Fibers found between the elastic fibers

Cells small, inconspicuous fibroblasts

Draw a representative field of the specimen. Label properly


6/11

6

LYMPHOID CONNECTIVE TISSUE

Specimen: cortex of lymph node

Study and locate:

Cortex shows areas of rounded condensations of lymphocytes called lymph nodules.

The central part of these nodules show mitotic figures and appear pale. This is the germinal

center of Fleming

Draw under the high power. Label properly.


7/11

7

II. CARTILAGEThis is a dense, firm but pliable tissue whose intercellular substance is solid but pliable and is

composed of organic and inorganic substances

TYPES OF CARTILAGE

A. HYALINE CARTILAGEThis can be recognized by its homogenous, translucent substance, the matrix.

SUBTYPES OF HYALINE CARTILAGE:

A.1 ADULT HYALINE CARTILAGE

SPECIMEN: Trachea

Study the section and identify the following structures:

Perichondrium the connective tissue sheath that surrounds the entire cartilage plate.

Chondrogenetic layer the inner layer in which chondroblasts are predominant

Matrix a more or less homogenous mass which takes the basic stain. It is supported by

collagenous fibers which are not visible under ordinary conditions

Lacunae the cavities in the matrix which contain the chondrocytes

Capsule the more deeply stained matrix that surrounds the lacuna

Chondrocytes the mature cartilage cellsNest cells refer to grouped chondroctes

Draw the structure of the entire field. Label properly


8/11

8

A.2 ARTICULAR HYALINE CARTILAGE

Found in articulating surfaces of the bone. Characterized by an incomplete perichondrium

A.3 FETAL HYALINE CARTILAGE

Found in the entire fetal skeletal system.

SPECIMEN: Developing bone

Study the section and identify the following structures:

Perichondrium the connective tissue sheath that surrounds the entire cartilage plate.

Chondrogenetic layer the inner layer in which chondroblasts are predominant

Matrix a more or less homogenous mass which takes the basic stain. It is supported by

collagenous fibers which are not visible under ordinary conditions

Lacunae the cavities in the matrix which contain the chondrocytes

Capsule the more deeply stained matrix that surrounds the lacuna

Chondrocytes the mature cartilage cells which are smaller and are arranged irregularly

Draw the structure of the entire field. Label properly

B. ELASTIC CARTILAGEThis type has yellow tinge in fresh condition because of the numerous elastic fibers which are

present in the matrix.

SPECIMEN: Epiglottis

Study and identify:

Elastic fibers numerous, vary in diameter; characteristic feature of this cartilage

Chondrocytes large, and do not fill the lacuna

Perichondrium has many elastic fibers of the cartilage

Draw the structure of the entire field. Label properly.


9/11

9

C. FIBROCARTILAGEThis closely resembles tendon in general appearance.

SPECIMEN: Intervertebral disc

Study and identify:

Collagenous fibers bundles of which are arranged in parallel line in the matrix

Chondrocytes distributed in rows in a well defined lacuna

Perichondrium none

Cell families not as mush as the other types

Draw an area containing 6 to 7 cells with the surrounding matrix. Label properly.

III. BONEIt is a type of connective tissue characterized by possessing a solid, hard, calcareous and brittle

ground substance (matrix)

SPECIMEN: decalcified bone (l.s. & c.s.)

Examine the l.s. & c.s. of a long bone and identify the following structures:

Periosteum the thin, outer connective tissue sheath which surrounds the bone

Periosteal lamella layer or layers of bony matrix which l ie beneath the periosteum.

Sharpeys fibers the septa-like continuation of the periosteum which extends into the bone

Marrow cavity the central cavity of the long bone which contains marrow cells

Endosteum the inner sheath which lies the marrow cavityEndosteal lamella layer or layers of bony matrix which lie external to the endosteum

Haversian systems cylindrical, branching, bony tubes; composed of the Haversian sanal,

haversian lamella, and osteocytes with radiating canaliculi.

Volkmans canal the small cavities for the passage of blood vessels through which are not

surrounded by concentric lamella.

Interstitial lamella occupies the interstices between the adjoining Haversian systems

Draw a section of the bone showing the above foregoing structures that you have observed. Label

properly.


10/11

10

IV. BLOOD VASCULAR TISSUEThis vascular or circulating tissue is a special connective tissue having an intercellular matrix of

fluid-like plasma in which a variety of cells are carried. These cells may be divided into two groups:

Erythrocytes or red blood corpuscles and the Leucocytes or white blood corpuscles.

SPECIMEN: Human blood

PROCEDURE

FRESH PREPARATION

1. Sterilize the tip of the finger with cotton wet with alcohol, then prick a sterile lancet2. Wipe the first drop of blood. A small drop is then placed at the center of a clean slide. A second

clean dry slide is held near its right hand end by the thumb and forefinger of the right hand. The

edge of one end of this slide is brought into close contact with the slide with blood held by the

left hand at 45 degree angle. The site of the contact should just be ahead of the blood drop. A

smooth, fast sliding motion of the spreader along the length of the horizontal slide deposits a

thin, uniform film of blood.

Study the slide prepared and identify:

Red blood cells seen as round refractile, non-nucleated structures arranged in rouleaux

formation.

Draw a small portion of the area and show how RBCs are arranged.

STAINED PREPARATION

1. The blood smear is allowed to dry by passing it high above the flame.2. Stain the preparation with Wrights stain as follows:

a. Cover the film with just enough stain for one minuteb. Add an equal amount of buffer solution. Allow this to remain on the slide for 4-5

minutes

c. Rinse slide by holding one end of the slide horizontally under a slow stream of tapwater.

d. Drain and air dry the slidee. Examine under oil immersion objective.

Study and identify the cells seen:

Erythrocytes appears pinkish with a pale center. Take note of the size and shape of the RBC

Leucocytes divided into:

Agranular WBC

1. Lymphocytes small spherical cells with large, deep blue nucleus surrounded by a narrow rimof cytoplasm


11/11

11

2. Monocytes large cells whose nucleus is usually eccentrically placed within the cell and is ovoidor kidney-shaped

Granular WBC

1. Neutrophils the most numerous WBC, the cytoplasm contiains fine, lilac granules. Thenucleus has several lobes connected by thin strands of chromatin

2. Eosinophils have large, bright pink granules which fill the cytoplasm. The nucleus is typicallybilobed

3. Basophils these are rare cells whose nucleus us bent in the form of S or N and is obscured bythe large, blue granules

Blood platelets the mallest formed elements. They are small basophilic masses containing granules.

They tend to form slumps in smears.

Draw each variety of blood cell seen. Color and label properly.

exercise 7 ct proper

Documents