Lecture 14: Fibrous Connective Tissue

Question 1

Functions of Connective Tissues

Answer 1

• structural framework of the body
• supports and interconnects other tissues
• also: protection, NRG storage, transport, defense

Question 2

Fibrous components of the Extracellular Matrix of CT (2)

Answer 2

1. elastin –> stretchable fiber

2. reticular fibers –> forms supportive meshwork

Question 3

Type-1 Collagen Fibers

Answer 3

• aligned and crosslinked to inc. tensile strength

diseases: Scurvy and Ehlers-Danlos Syndrome

Question 4

Amorphous Ground Substance components of Extracellular Matrix of CT (4)

Answer 4

1. proteogylcans –> sulfates
2. hyaluronan
3. glycoproteins –> cytokines, growth factors
4. extracellular proenzymes

Question 5

Embryonic Connective Tissue

Answer 5

• rich in extracellular matrix and mesenchymal stem cells

- in umbilical cord (Wharton’s Jelly)

Question 6

Loose Connective Tissue

Answer 6

• areolar
• support and bind other tissues, defend from infection
• found immediately beneath membranous epithelia (lamina propria)

Question 7

Adipose Connective Tissue

Answer 7

• loose CT
• abundant adipocytes and sparse ECM
• reserve energy source and insulates against heat loss
• padding/cushioning organs

Question 8

Brown vs White Fat

Answer 8

White - energy storage, insulation, cushioning

Brown - key thermogenic tissue, abundant in newborns

Question 9

Reticular Connective Tissue

Answer 9

• loose CT
• rich in RETICULAR FIBERS
• open framework = labyrinth for holding free cells
• houses blood cells and immune cells outside of blood/lymphatic vessels

Question 10

Dense Irregular Connective Tissue

Answer 10

• extracellular membrane tightly packed

- FIBROBLASTS are principle cell type

Question 11

Dense Regular Connective Tissue

Answer 11

• ECM tightly packed
• FIBROBLASTS are principle cell type
• resists pulling forces, poorly vascularized
• in tendons, ligaments, aponeuroses, dense fascia

Question 12

Elastic Connective Tissue

Answer 12

• Dense connective tissue
• ELASTIC FIBERS are principle cell type
• allows recoil of tissue following stretching
• in blood vessel walls, bronchiole tubes, special ligaments

Question 13

What is Marfan’s Syndrome?

Answer 13

• autosomal dominant (weak elastin –> mutation in fibrillin-1 gene)
• targets: ocular, skeletal, cardiovascular systems
• tall with long arms and legs

Question 14

What is the purpose of fibroblast cells?

Answer 14

• produce collagen, elastin, reticular fibers, proteoglycans, and glycoproteins in ECM