L6 Classification Of CT Proper And Embryonic

Question 1

How is connective tissue classified

Answer 1

1-embryonic CT that includes:

a) mesenchymal CT
b) mucous CT

2-connective tissue proper:

a) loose areolar
b) dense CT regular and irregular
c) reticular
d) elastic

3-special types:
a)cartilage
b)bone
C) blood

Question 2

Describe mesenchymal CT

Answer 2

Present only in embryo and consists of mesenchymal cells in a gel like ground substance containing scattered reticular fibers
Mitotic figures frequently observed in mesenchymal cells
Present in pulp of teeth in adults

Question 3

Describe mucous tissue

Answer 3

Loose amorphous CT exhibiting jelly like matrix primarily composed of hylaurnoic acid and sparsely populated with type 1 and 3 collagen fibers and fibroblasts
Wharton’s jelly in umbilical cord

Question 4

1-Describe loose areolar tissue
2-Its site
3-Componentes
4-structural correlation to site and function

Answer 4

1-formed of a loose arrangement if fibers and dispersed cells embedded in a gel like ground substance
2-site:under epithelium where it is called lamina propria in mucous membranes such as alimentary tract or dermis in skin and surrounds blood vessels
3-components:loose connective tissue characterized by abundant ground substance and tissue fluid housing the fixed connective tissue cells and all types of fibers
4-correlation to function: tissue lies immediately beneath thin epithelia of digestive tract and respiratory tract, this is where body first attacks antigens,bacteria and other foreign invaders
So CT may contain many transient cells responsible for inflammation allergic reactions and immune response

Question 5

What causes edema

Answer 5

Extracellular fluid normally returns to blood capillaries or enters lymph vessels to be returned to blood
A potent and prolonged inflammatory response causes accumulation of excess tissue fluid within loose connective tissue beyond what can be returned via capillaries and lymph vessels

Question 6

Describe dense CT

Answer 6

Contains same components as loose CT but with more fibers and fewer cells
Less flexible and more resistant to stress
Divided to
Regular and irregular

Question 7

Describe regular dense CT

Answer 7

Regularly arranged collagen bundles that have regular orientation
collagen bundles are densely packed and oriented in to parallel cylinders or sheets that resist tensile forces
Sites: present in tendons of muscle and ligaments of joints
Thin sheet like fibroblasts are located between bundles of collagen with their long axes parallel to the bundles

Question 8

Describe elastic CT

Answer 8

Regularly arranged collagen bundles that have regular orientation

Coarse branching elastic fibers with only a few collagen forming networks
The elastic fibers are arranged parallel to one another and form either thin sheets or fenestrated membranes
Sites: present in walls of large arteries and some ligaments of vertebral column

Question 9

Describe the dense irregular type

Answer 9

Randomly oriented collagen bundles such as in dermis of skin and in capsule covering solid organs such as kidney and lymph nodes

Limited amount of ground substance

Fibroblasts are most abundant cells

Question 10

Describe reticular CT

Answer 10

Type 3 collagen is the major fiber component of reticular tissue
Collagen fibers form mesh like networks interspersed with fibroblasts and macrophages
Reticular tissue forms the architectural framework(fine stroma) of adipose tissue, bone marrow, lymph nodes and spleen