CTO Quiz 4

Question 1

Which cells of bone marrow can regenerate themselves?

Answer 1

Pleuripotent and multipotent stem cells can reproduce themselves - all other cells are committed to differentiating

Question 2

What are the changes in cell appearance of blood cell precursors as blood cell differentiate?

Answer 2

• Cells become smaller
• lose nuceloli
• develop granules
• nucleus assumes more adult shape

Question 3

Most important growth factors in granulocyte production and what produces them?

Answer 3

G-CSF - produced by macrophages, endothelium, fibroblasts

CM-CSF - produced by lymphocytes, endothelium, fibroblasts

Question 4

What is the most important growth factor in stimulating platelets and where is it made?

Answer 4

Thrombopoeitin - produced by liver and kidney

Question 5

When does bone marrow start producing RBCs?

Answer 5

About the middle of fetal life

Question 6

What kind of cells would you expect to find in the extravascular compartment of the bone marrow? What kind of fibers?

Answer 6

Hematopoietic cells, adventitial cells, and fat cells

reticular fibers

Question 7

Structure of vascular compartment of bone marrow?

Answer 7

Venous sinusoids - discontinuous and fenestrated endothelium

Question 8

How long does erythropoeisis take?

Answer 8

7 days

Question 9

How long dos granulopoeis take?

Answer 9

14 days - first week = rapid reproduction of cells

second week = dominated by maturation

Question 10

Megkaryocyte

Answer 10

multilobed nucleus, has cytoplasmic protrusion rich in actin and microtubles (dynein). Many infoldings of the plasma membrane called “demarcation membranes” that provides extra surface area

Question 11

Myeloid to erythroid ratio

Answer 11

3:1

Question 12

Keratinocytes

Answer 12

Dominant cells of the epidermis (they make keratin)

Question 13

Layers of the epidermis

Answer 13

Stratum corneum, Stratum granulosum, Stratum spinosum, stratum basale

Question 14

How long does it take to replace your epidermis?

Answer 14

a month

Question 15

What is the stratum basale?

Answer 15

Deepest layer of epidermis. 1 cell layer thick - all touching basal lamina (simple cuboidal or short columnar). basophilic - producing keratinocytes – they form stem cells for regenerations. Contain melanosomes that are produced by melanocytes (forms brown cap of nuclei to protect DNA)

Question 16

What is the stratum spinosum?

Answer 16

Thickest layer - lost attachment to basment membrane, conected to one another by desmosomes that vie the cells the “spines”. Keratin groups into tonofibrils that attach to desmosomes and hold cells together

Question 17

What is the stratum granulosum?

Answer 17

Contain basophilic granules of keratohyaline (including protein called FILAGGRIN). Last living layer of cells (more flattened shape).
- Also have lamellar bodies/granules, which spill out of cell as lipids to make skin waterproof. In thick sin there is a very thin, highly eosinophilic layer at the superficial transition area called the STRATUM LUCIDUM

Question 18

What other kinds of cells are present in the skin?

Answer 18

Melanocytes, Langerhans (antigen presenting), Merkels (sensory)

Question 19

What are melanocytes?

Answer 19

• derived from neural crest cells
• have processes that contact up to 30 keratinocytes
• manufacture eumelanin and pheomelanin
• processes phagocytesd by stratum basale cells –> metabolize product into pigment.
• color of skin depends on rate and transfer to keratinocytes not number of melanocytes

Question 20

What are the layers of the dermis?

Answer 20

1. Papillary Layer - loose connective tissue with blood vessels - makes fingerlike projections and increase contact area. Responsible for fingerprints. Also contains nerves, fibroblasts and macrophages.
2. Reticular Layer - dense connective tissue. Comprised of collagen and elastin fibers. Sweat glands stick down through this layer

Question 21

What is the structure of the hair follicle?

Answer 21

Root sheath with a bulb at the bottom. Dermal papilla that enters bulb and nourishes it. The hair matrix (growing part) surrounds the pailla and melanocytes that provides hair color
- medulla (inner layer)
- cortex (middle layer)
- cuticle (outer layer - highly keratinized)
PILOSEBACEOUS UNIT:
- arrector pilli muscles
- sebaceous glands (produce sebum)

Question 22

What kind of glands are sebaceous glands?

Answer 22

• use holocrine secretion
• produce sebum (oily)
• found in hair follicle

Question 23

What is the structure of eccrine glands and where are they found?

Answer 23

• Simple coiled tubular glands found in deep dermis and hypodermis
• merocrine secretion
• evaporative cooling
  and secrete salt, urea lactate
• they have myoepithelial cells to help expel secretion

Question 24

What are apocrine sweat glands and where are they found?

Answer 24

• simple coiled tubular
• found in axilla and anogenital region
• large lumen because secretions are stored in the lumen
• use merocrine secretion (but odorless)
• secrete phermones

Question 25

Structure of mammary glands?

Answer 25

- compound tubuloaccinar glands - develop along the milk line - use apocrine (lipids) and merocrine (antibodies, proteins, sugars) - under influence of hormones (prolactin) - ductal system develops during puberty --> develops alveoli (simple cuboidal or columnar with myoepithelium) - milk released into lactiferous ducts (simple cubodial) then lactiferous sinuses

Question 26

What kind of epithelium cells lines the nasal cavity, trachea, and main stem bronchi?

Answer 26

Pseudostratified columnar w/cilia and goblet cells

Question 27

What are the functions of the nasal mucosa?

Answer 27

It warms, and moistens air, traps particles in the air. It also contains olfactory epithelium

Question 28

What epithelium over the vocal cords?

Answer 28

Non-keritinized stratified squamous

Question 29

What is the structure of the trachea?

Answer 29

- prominent lamina propria with serous and mucous glands - submucuosa contains hyaline cartilage in C shape - smooth muscle (prominent posteriorly) where there is also a lot of fibroelastic tissue - entire organ surrounded by adventitia - lymphoid tissue prominent in lamina propria (MALT)

Question 30

Differences between trachea and bronchi?

Answer 30

Bronchi have cartilage plates (not c-shaped) | more smooth muscle

Question 31

What is the only complete cartilage ring in the respiratory system?

Answer 31

Cricoid cartilage in lowest part of the larynx

Question 32

Types of cells in epithelium of bronchi?

Answer 32

- Columnar cells with cilia (muscucillary escalator) - brush cells (sensory) - neuroendocrine cells (02-K sensitive receptor) - goblet (mucous) - basal cells (regenerative)

Question 33

Differences between bronchi and brochioles?

Answer 33

Bronchioles: - more smooth muscle and elastic fibers - cartilage and glands of the lamina propria are gone - respiratory epithelium becomes simple cuboidal or columnar - clara cells replace goblet cells --> secrete GAG, surfactant like material, prevent toxin harming, regenerative properties

Question 34

What is the minimum membrane for gas exchange?

Answer 34

Type I pneumocyte, common basement membrane, and alveolar capillary epithelial cell

Question 35

What do nerves do in the lung

Answer 35

Parasympathetic (vagus) -- constrict bronchial smooth muscle and increase grandular secretion Sympathetic (cardiac) -- dilate bronchial smooth muscle, decrease secretion. Sensory fibers detect stretch of the elastic connective tissue (Hering-Breurer afferents)