Tishk International University

Faculty of Pharmacy

Department of Pharmacy

HISTOLOGY – 110

Primary Basic Tissues of the Body

Connective Tissue –Part- B

First Grade – Spring Semester 2019-2020

Instructor :Prof. Dr. Hiwa Bakir Banna

1

Specialized form of connective tissue

a- Cartilage

It is a specialized form of connective tissue composed of cells called Chondrocytes which lie in

lacuna embedded in a firm matrix . Cartilage is flexible and strong, and is resilient to

compression. It forms mechanical support to soft tissues and is important for bone development

from fetal period to puberty .

Cartilage does not contain blood vessels (it is avascular) or nerves (it is aneural). Nutrition is

supplied to the chondrocytes by diffusion also and does not repair (no regeneration, or very

slow regeneration)?.

On the basis of their matrix characteristics cartilages are divided in to three types :

1-Hyaline cartilage (Hyaline cartilage is the most widely distributed type).

2- Elastic cartilage

3- Fibrocartilage

1-Hyaline cartilageAmorphous, firm matrix with a strong network of collagen fibers covered

externally by perichondrium

Chondrocytes lie in lacunae,

Supports, reinforces, cushions, and resists compression

Found in embryonic skeleton, the end of long bones, nose, trachea, and larynx

Forms the costal cartilage

chondrocytes inside lacuna

Perichondrium

perichondrium

?

2-Elastic Cartilage

Similar to hyaline cartilage but with more elastic fibers

Maintains shape and structure while allowing flexibility

Supports external ear (pinna) and the epiglottis

3-Fibrocartilage Cartilage

Strongest of the three types of cartilage no perichondrium.

Matrix similar to hyaline cartilage but less firm with thick collagen fibers

Provides tensile strength and absorbs compression shock

Found in intervertebral discs, and in discs of the knee joint

b- Bone (Osseous Tissue)

Hard, calcified matrix with collagen fibers found in bone

The basic unit is osteon(Haversian system).

The haversian canal generally contains capillaries and nerve fibers

Osteocytes are found in lacunae and are well vascularized

Supports, protects, and provides levers for muscular action

Stores calcium, minerals, and fat

Marrow inside bones is the site of hematopoiesis

Bone Tissue (osseous tissue)

Bone structure:

1-Osteon – basic unit of compact bone

2-Lamellae – concentric circles of matrix

3-Lacunae – spaces in the matrix that house cells

4-Osteocytes – mature bone cells

5- Osteoblasts- immature bone cells

6- Osteoclasts- bone resorption cells ?

7--Endosteum(inner lumen c.t covering) &

Periosteum (outer c.t. covering)

Hyaline cartilage

c-BloodRed and white cells in a fluid matrix (plasma)

Contained within blood vessels

Plasma is the liquid part of blood containing clotting factors (fibrinogen)

Serum is the liquid part of blood after clotting(coagulation).

Functions in the transport of respiratory gases, nutrients, wastes and other

substances.

Blood supply and regeneration of connective tissues

Connective tissues can have various levels of vascularity.

1. Cartilage is avascular (no regeneration), while dense connective tissue is

poorly vascularized .

2. Others, such as bone and loose areolar connective tissue, are richly

supplied with blood vessels and nerves.

3. Connective tissue cells are able to reproduce but not as rapidly as epithelial

cells.

Connective tissue coverings of major tissues:

a- epithelia : not covered by C.T but rests on C.T called

basement membrane and supported by loose C.T ..??

b- Bone : endosteum and periosteum ?

c- Cartilage : Perichondrium ?

d- Muscle : endomysium, perimysium and epimysium

e- Nervous : endoneurium, perineurium and epineurium.

Question Time:

Summary Interactive Revision and of Major Points1- Structure and components of C.T

2- Main Types and distribution in the body

3- Functions

4- C.T is all tissues in the body Except 1….2……and 3…..?

5- What are these connective tissue cells ?:

cytes, blasts and clasts

Connective, Muscle and nerve tissuesConnective , muscle and

nerve tissues

END of Connective Tissue

Next Lecture is :Muscle Tissue

17

References:

Wheater's Functional Histology by Barbara Young Elsevier 6TH ed. Churchill

Livingstone.edinburgh

Junqueira's Basic Histology: Text and Atlas, 13th ed / McGraw- Hill.

HISTOLOGY A TEXT AND ATLAS by Ross & Pawlina / Lippincott Williams and

Wilkins ,Fifth edition.

Textbook of Histology by Leslie Gartner pub: Elsevier 4th EDITION

Histology Books, Ebooks & Journals | US Elsevier Health

www.us.elsevierhealth.com/medicine/histology

Normal histology, with special reference to the ... - Internet Archive

https://archive.org/details/normalhistologyw00pier. Internet Archive.

Di Fiores Atlas of Histology with functional correlations. 12th ed. Wolters Kluwer/

Lippincott,& Wilkins Int.

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