Connective Tissue Histology

Question 1

List the types of connective tissue and discuss the characteristics that differentiate one from another?

Answer 1

Embryonic Connective Tissue
(mostly mesenchymal cells)

Adult Connective Tissue
(loose connective tissue vs. dense connective tissue)

Special Connective Tissues (Blood, Fat, Cartilage, Bone)

Question 2

Functions of Connective Tissue?

Answer 2

• protect the underlying tissues
• allow for nutrient exchange
• immunological role
• energy source (adipocytes)

Question 3

List the three types of fibers that are found in the ECM and tell me their functions in the ECM?

Answer 3

*** All produced by the Fibroblast Cell Type–>

Collagen Fibers–> they give tensile strength (Ehler-Danlos Syndrome, Scurvy)

Elastin Fibers–> they give elasticity to the ECM (Marfan’s Syndrome; cardiovascular disease)

Reticular Fibers–> give strength to the ECM structurally

Question 4

What is ground substance in the ECM and what composes it?

Answer 4

Ground Substance is the gel-like substance that surrounds the fibroblasts and the other types of cells as well as the proteins that are built within it.

Question 5

What is the general functions of mesenchymal stem cells?

Answer 5

Mesenchymal Stem Cells are multipotent stem cells that give rise to blood cells, chondrocytes, adipocytes, mast cells, fibroblasts, etc.

Question 6

What are the functions of the fibroblasts, adipocytes, plasma cells, macrophages, leukocytes, mast cells?

Answer 6

Fibroblasts–> build the ECM with fibers

Adipocytes–> gives energy source for the tissue

Plasma Cells–> give immune functionality in ECM

Macrophages and leukocytes + mast cells

Question 7

Cell Types found in loose connective tissue?

Answer 7

Loose Areolar Connective Tissue–>
All 3 cell types: fibroblasts, adipocytes, mesenchyme stem cells
Found: deep to the skin and the muscles, blood vessels, nerves, and organs

Adipose Connective Tissue–>
lots of adipocyte cells and no other ECM cells/ ECM Matrix
Found: under skin, around organs, breasts, buttocks

Reticular Connective Tissue–>
reticular fibers; forms an open framework to strong network
Found in: Bone marrow, lymph nodes, spleen, liver

Question 8

Cell types found in dense connective tissue?

Answer 8

Irregular Dense Connective Tissue–>
mostly fibroblasts; thats why you have so MUCH COLLAGEN fibers
Found in: dermis of the skin and in capsules of internal organs

Regular Dense Connective Tissue–>
Mostly fibroblasts; regular collagen fibers that go straight across
Found in: aponeurosis, tendons, ligaments

Question 9

Embryonic connective tissue and adult connective tissue difference?

Answer 9

• difference in the mesenchymal stem cells

Question 10

What are fixed cell types in the ECM?

Answer 10

Fibroblasts, adipocytes, mesenchyme stem cells

Question 11

What are the wandering cell types of the ECM?

Answer 11

Macrophages, mast cells, leukocytes, plasma cells

Question 12

What is marfan’s syndrome?

Answer 12

Mutation in Fibrillin-1 gene causing elastic fiber production problems which is important for blood vessels–> heart problems

Question 13

Health consequences of prolonged Vitamin C deficiency?

Answer 13

Scurvy Disease which is problem with the Collagen fiber synthesis

Problem: teeth fall out