Lesson 8:

Question 1

what arises from the ectoderm and mesoderm?

Answer 1

The epithelium.

Question 2

Avascular, a basement membrane, shows up with PAS stain - These are all characteristics of?

Answer 2

Epithelium.

Question 3

Which basement membrane domain provides protection of the epithelial surface and absorbs substances?

Answer 3

Apical domain.

Question 4

The ________________ domain anchors the epithelial cells to each other and to the basement membrane.

Answer 4

Basolateral domain.

Question 4

Tumor proteasomes can degrade the basal lamina of the basement membrane, allowing cancerous cells to reach the blood flow and spread to other tissues - What is this called?

Answer 4

Metastasis.

Question 5

What are the 2 layers of the basement membrane? Describe them:

Answer 5

1. Basal lamina - made of collagen type IV.
2. Reticular lamina - made of collagen type III. Has reticular fibers.

Question 6

True or false: The basement membrane is made primarily of glycoproteins, and therefore is best viewed when stained with H&E.

Answer 6

FALSE - Glycoproteins are best viewed in PAS, not H&E.

Question 7

Failure of collagen type III and/or type IV, will result in what condition?

Answer 7

Kidney disease.

Question 8

Which basement membrane disease is characterized by progressive neuropathy, causing hematuria (blood in urine). Is transmitted through an X-Linked recessive gene. and is a result of a mutation in the COL4A5 gene?

Answer 8

Alport syndrome.

Question 9

A basement membrane autoimmune disease that has progressive glomerulonephritis and pulmonary complications. Is caused by Anti-COL4A3 antibodies binding to basal lamanae.

a. Alport syndrome.
b. Osteogenesis imperfecta.
c. Good pasture syndrome.
d. Benign familial hematuria.

Answer 9

C - Good pasture syndrome.

Question 10

True or false: Benign familial hematuria is caused by a dominant inherited mutation of COL4A3.

Answer 10

True!

Question 11

Components of connective tissue proper:

Answer 11

1. Fibroblasts - Do secretion of CT precursors.
2. Extracellular fibers - collagen and elastin.
3. Extracellular matrix - amyloid.

Question 12

The ____________ contains 20% of our bodily fluids.

Answer 12

Interstitium.

Question 13

What is a 3-chain fibrous protein that coils, generates tensile strength, and has fibroblasts/osteoblasts/chondroblasts/odontoblasts to secrete it?

Answer 13

Collagen.

Question 14

Steps of intracellular collagen formation:

Answer 14

Procollagen -> modified by procollagen peptidase -> tropocollagen.

Question 15

Steps of extracellular collagen formation:

Answer 15

Tropocollagen -> self-assembly via lysyl hydroxylase and oxidase -> collagen fibrils -> aggregates -> Collagen fibers.

Question 16

Which collagen condition interferes with the conversion of procollagen to collagen by one of two mechanisms? Reduces tensile strength in tendons. and is a product of mutation in COL1A1 and COL1A2 -

a. Osteogenesis imperfecta.
b. Ehlers-danlos syndrome.
c. Stricklers syndrome.
d. Amyloidosis.

Answer 16

B - Ehlers-danlos syndrome.

Question 17

Which collagen condition causes myopia, hypoplasia of the jaw, and arthritis - has type II collagen - and has the COL2A1 gene mutated?

a. Osteogenesis imperfecta.
b. Ehlers-danlos syndrome.
c. Stricklers syndrome.
d. Amyloidosis.

Answer 17

C - Stricklers syndrome.

Question 18

Which collagen condition causes bones fragility, has COL1A1 mutated, and has no normal bone ossification due to a lack of type I collagen.

a. Osteogenesis imperfecta.
b. Ehlers-danlos syndrome.
c. Stricklers syndrome.
d. Amyloidosis.

Answer 18

A - Osteogenesis imperfecta.

Question 19

Explain the two mechanisms by which ehlers-danlos syndrome may form:

Answer 19

1. Mutated procollagen peptidase will remove the non-helical ends of procollagen, making defective fibrils.
2. Mutation of lysyl hydroxylase - causing a decrease in strength of collagen fibers.

Question 20

Osteogenesis imperfecta type 1:

Answer 20

Mild, non-deforming.

Question 21

Osteogenesis imperfecta type 2:

Answer 21

Perinatal lethal. Pretty bad.

Question 22

Osteogenesis imperfecta type 3:

Answer 22

Very severe, lots of deformity.

Question 23

Osteogenesis imperfecta type 4:

Answer 23

Mild to moderate symptoms and deformity.

Question 24

_____________ _______________ dates back to 1000 B.C.

Answer 24

Dentinogenesis imperfecta.

Question 25

Smooth muscle, fibroblasts, chrondroblasts, chondrocytes, all produce this -

Answer 25

Elastic fibers.

Question 26

What are the two special amino acids in elastin, and what is their function?

Answer 26

1. Desmosine and isodesmosine.
2. Cross-links elastin fibers and enables stretching and recoil.

Question 27

Formation of elastin:

Answer 27

Proelastin –> Tropoelastin + fibrillin –> immature elastic fibers –> mature elastic fibers.

Question 28

Fibrillin 1 and 2 are needed for what?

Answer 28

Skeletal development.

Question 29

Fibrillin 1 only is needed for what?

Answer 29

Cardiovascular development.

Question 30

Disease has a