Lecture 3 - Connective Tissue Flashcards Preview

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Flashcards in Lecture 3 - Connective Tissue Deck (47):
1

Function of connective tissue (x3)

1. Structural Support
2. Nutrition
3. Defense

2

What makes up connective tissue?

Support Cells
Extracellular Matrix (Fibers/Ground substance)
Blood or lymph vessel

3

Main function of fibroblast?

make fibers

4

Where would you expect to see a lot of active fibroblasts?

Growing individuals
Wound Healing

5

3 Types of fiber in connective tissue

1. Collagen
2. Reticular
3. Elastic

6

Collagen formation

Fibroblast + Vitamin C = procollagen --> collagen --> fibril --> fiber

7

Type I collagen function

Tensile Strength

8

What contains lots of type I collagen?

Skin, ligaments, tendons

9

Where is type IV collagen found?

Basal Lamina --> lamina densa

10

What attaches the cell to type IV collagen?

Laminin

11

Where can you find type VII collagen?

BM --> anchoring fibril

12

Where do you find type III collagen?

Reticular Lamina w/ in BM
Fibers are in spleen, lymph nodes, liver, endocrine glands

13

What is the main function of fibroblasts?

Make fibers

14

Where do fibers and ground substance come from?

Extracellular Matrix

15

What types of cells are found in connective tissue? (x8)

1. Adipocytes
2. Chondrocytes
3. Osteocytes
4. Fibroblasts
5. Leukocytes
6. Macrophages
7. Mast Cells
8. Plasma Cells

16

Where are adipocytes found?

CT of many organs

17

Where are chondrocytes found?

Cartilage

18

Where are osteocytes found?

Bone

19

What is the most common cell in CT

Fibroblasts

20

In general, what is the roll of mast cells?

Release mediators that contribute to the allergic response

21

In general, what are macrophages involved with?

Phagocytosis

22

Shape of plasma cells?

Nucleolus in the middle, spokes around the side

23

Why does cytoplasm stain purple?

Active cells produce protein (pink, acidophilic) and RNA (RER, blue, basophilic). When these colors mix, they produce purple.

24

What is the function of plasma cells?

Produce antibodies to an antigen that will trigger an immune response.

25

What is the most common type of collagen?

Type I

26

What is the process of forming a collagen fiber?

1. Collagen fiber + Vitamin C
2. Procollagen plus processing
3. Fibril formation which is striped
4. Bundle to form fiber

27

Where is Type I collagen most commonly found?

Ligaments, Skin, and Tendons

28

What is the major function of Type I collagen?

Tensile Strength

29

Where is Type IV Collagen found?

Basal Lamina

30

What attaches to type IV collagen?

Laminin which connects to the transmembrane protein integrin. Forms the hemidesmosome

31

Where can you find Type VII collagen fibers?

Basement membrane- anchors Type IV collagen to Type III collagen (reticular fibers)

32

The diameter of a collagen fibril ranges from 20-90 nm. How can you see type VII collagen fibrils using a light microscope?

Immunohistochemistry to type VII collagen- use fluorescent tagged antibody

33

Where do you find Type III collagen?

Reticular fibers in the reticular lamina of the basement membrane. They are most abundant in the spleen, lymph nodes, liver, and endocrine glands.

34

Reticular fibers are heavily glycosylated. Will they stain with H&E?

No, H&E does not stain glycogen.

35

What is the major function of reticular fibers?

Support individual cells.

36

What makes up elastic fibers?

Elastin

37

What do fibroblasts secrete?

Fibrilin and Elastin to form elastin bound microfibrils

38

How do elastic fibers differ from collagen?

They are not as uniformly shaped as collagen fibers.

39

What is the ground substance made of?

1. Glycoaminoglycans (GAGs)
2. Proteoglycans
- makes up a semifluid gel linking cells and ECM (Laminin)

40

How does loose CT differ from dense CT?

1. Loose CT has lower fiber to cell/ground substance ratio than dense CT
2. Loose CT is well vascularized, dense regular CT is not
3. Loose CT is more flexible than dense CT
4. Loose CT is less resistant to stress than dense CT

41

Where do you find dense regular CT?

Tendons and Ligaments

42

Where do you find dense irregular CT?

Skin

43

Where would you find elastic tissue?

Elastic ligaments of spine and Aorta

44

What is adipose tissue?

Loose connective tissue dominated by fat cells or adipocytes

45

What are the functions of white adipose tissue?

1. Cushion other organs
2. Endocrine Organ
3. Insulator
4. Shock Absorption
5. Store triglycerides

46

What would be the most common type of fiber in adipose tissue?

Reticular fibers (adipocytes are surrounded by Type III collagen)

47

What is the main function of brown adipose tissue?

Heat production