Histology Connective Tissues

Question 1

Connective Tissues Functions

Answer 1

Physical support, packing material, transports nutrients and oxygen

Question 2

Supportive connective tissues (also hard CT)

Answer 2

Cartilage and Bone

Question 3

Loose connective tissue

Answer 3

Filler between cells. Areolar, adipose, hematopoietic (blood forming), and reticular (lymph nodes)

Question 4

Dense connective tissue

Answer 4

Dense irregular like skin (collagen bundles in multiple directions, strong compressive and shear strength), and dense regular like tendon and ligament (fibers in same direction, strong tensile strength)

Question 5

All connective tissues have 3 components

Answer 5

Cells, and Extracellular matrix of fibers and ground substance

Question 6

Collagen formation

Answer 6

Made in fibroblasts, osteoblasts and chondroblasts. Vitamin C adds OH that combine and create pro collagen (3 strands). pro collagen peptidase cuts off ends and creates tropocollagen. Tropocollagen combine to make collagen fibers.

Question 7

Components of Elastic fibers

Answer 7

Elastin core with fibrillin on outside

Question 8

Ground substance

Answer 8

Proteoglycans like glysoaminoglycans, with base made of Hyaluronic acid. Linker proteins connect to core proteins with chondroitin and keratin sulfate chains (lots of OH groups attract water). Fills in space to allow cells to migrate through.

Question 9

Connective Tissue Proper

Answer 9

Loose and dense CT

Question 10

Principal cell type in dense CT

Answer 10

Fibroblast (dividing cell) and fibrocyte (no longer dividing)

Question 11

Hematopoietic cells

Answer 11

dendritic reticular cells, lymphocytes, mast cells.

Erythrocytes, monocytes, lymphocytes, granulocytes (neutrophils, basophils, eosinophils)

Question 12

Most common fibers in CT

Answer 12

Collagen and elastin

Question 13

Mesenchymal cells

Answer 13

can differentiate into fibroblasts, adipocytes, osteoblasts, and chondroblasts

Question 14

Adipocyte Brown fat

Answer 14

multilocular, generates heat

Question 15

Adipocyte White fat

Answer 15

unilocular, storage of triglycerides (energy), provides protection, packing

Question 16

Chondroblasts

Answer 16

Outer edge of cartilage, make cartilaginous matrix

Question 17

Chondrocytes

Answer 17

in middle - maintain existing matrix

Question 18

Perichondrium

Answer 18

Outer surface of cartilage has chondroblasts and fibrous tissues

Question 19

Vasculature of cartilage matrix

Answer 19

Avascular, gets nutrients by diffusion

Question 20

How does cartilage change with age?

Answer 20

With age, cartilage dies and can be replaced by bone

Question 21

Growth of cartilage

Answer 21

Interstitial (within existing matrix) and appositional (on outer surface on the top of the matrix)

Question 22

Growth of bone

Answer 22

Only appositional (on outer surface)

Question 23

Ground substance of cartilage

Answer 23

Aggrecan - similar hyaluronic acid core with sulfated glycosaminoglycans (chondroitin and keratin sulfate)

Question 24

Types of Cartilage

Answer 24

Hyaline cartilage, most common, articular cartilage is a form of hyaline.
Fibrocartilage (thick bundles strong).
Elastic cartilage (Ex. Ear)

Question 25

Cells of Bone

Answer 25

Osteoblasts (make new bone), Osteocytes (maintain structure), Osteoclasts (remove bone)

Question 26

Most abundant fiber in bone

Answer 26

Collagen

Question 27

Bone Ground substance

Answer 27

Glycoaminoglycan with hyaluronic acid and side chains, also has hydroxyapatite which is calcium and phosphate (crystalline shape that makes bone hard)

Question 28

Roles of collagen and hydroxyapetite

Answer 28

Collagen makes bone strong, while hydroxyapatite makes it hard

Question 29

Compact bone layout

Answer 29

Haversian arteries travel through small hole called Haversian canals. Layers around this are called Lamella. Inside that are osteocytes. Osteon is unit of all of this.

Question 30

Cancellous (spongy) bone layout

Answer 30

Lining inside of bone is a layer of osteoblasts called the endosteum. Inside is bone marrow, which can have hematopoietic or fat cells and lots of blood vessels. bone shelves form latticework for strength. Found in vertebra or plates of skulls

Question 31

Periosteum

Answer 31

Around bones that has fibrous layer and osteoblasts

Question 32

How is bone made?

Answer 32

Osteoblast connects to osteocyte, lays down osteoid as organic matrix. That gets calcified and becomes bone. It keeps making osteoid until it is covered (can no longer divide) and turns into osteocyte

Question 33

Can mine bone for what two things?

Answer 33

Calcium and phosphate