Histology Exam 1

Front 1

What is the signal that directs proteins from the golgi to lysosomes?

Back 1

mannose-6-phosphate

Front 2

Primary lysosome

Back 2

lysosomes which have not yet received substrates for digestion

Front 3

Secondary lysosomes

Back 3

results from the fusion of primary lysosomes with their target

Front 4

Lipofuscin granules (or residual bodies)

Back 4

senescent lysosomes with undigestible materials

Front 5

Constitutive pathway (from Golgi)

Back 5

proteins not destined for lysosomes or secretory granules are transported directly to the plasma membrane; default pathway; e.g. integral membrane proteins, collagen

Front 6

Peroxisomes

Back 6

oxidize a wide range of organic substances including very long chain fatty acids; convert ethanol to acetaldehyde; catalase is important enzyme in degrading hydrogen peroxide

Front 7

Adrenolreukodystrophy

Back 7

disruption in oxidation of very long chain fatty acids; inherited X-linked disorder; symptoms caused by accumulation of lipids in the brain and adrenals

Front 8

Zellweger syndrome

Back 8

congenital disease with mutation in proteins that transport peroxisomal enzymes into peroxisome; leads to improper formation of myelin sheath in brain; patients usually die before 6 months of age

Front 9

No mitochondria in...

Back 9

Red blood cells and terminal keratinocytes

Front 10

Inner mitochondiral membrane in steroid producing cells

Back 10

the cristae may have tubulovesicular appearance

Front 11

Cytochrome C

Back 11

located in mitochondria; important factor in initiating apoptosis

Front 12

Electron-dense granules in mitochondrial matrix

Back 12

store calcium ions

Front 13

mitochondrial myopathies

Back 13

present in young adulthood and manifest with proximal muscle weakness, sometimes with severe involvement of the extraocular muscles involved in eye movements; may also be accompanied by neurological symptoms, lactic acidosis, and cardiomyopathy

Front 14

Inner nuclear membrane

Back 14

distinct from the endoplasmic reticulum in its ability to bind chromatin and lamins; supported by a rigid network of intermediate filaments

Front 15

3 types of heterochromatin

Back 15

1. Marginal heterochromatin - found at the periphery of the nucleus
2. Karyosomes - discrete bodies of chromatin irregular in shape and size found throughout the nucleus
3. Nucleolar-associated chromatin - found in association with the nucleolus

Front 16

Nucleolus - Fibrillar centers

Back 16

contain DNA loops with rRNA genes and transcription factors

Front 17

Nucleolus - Dense fibrillar component (pars fibrosa)

Back 17

contains ribosomal genes that are being translated and large amounts of RNA

Front 18

Nucleolus - Granular component (pars granulosa)

Back 18

the site for ribosome assembly and is made of densely packed clusters of pre-ribosomal particles

Front 19

Microtubules not present in...

Back 19

erythrocytes

Front 20

Cells without microtubule-organizing center...

Back 20

neurons and erythrocytes

Front 21

Intermediate filaments - lamins

Back 21

form nuclear lamina

Front 22

Intermediate filaments - keratins

Back 22

in epithelial cells

Front 23

Intermediate filaments - vimentin

Back 23

in the fibroblasts of connective tissue

Front 24

Intermediate filaments - desmin

Back 24

in muscle cells

Front 25

Intermediate filaments - glial fibrillary acidic proteins

Back 25

in glial cells (the support cells of the nervous system)

Front 26

Intermediate filaments - neurofilaments

Back 26

in neurons

Front 27

Functions of intermediate filaments

Back 27

1. spread tensile forces and maintain cell architecture
2. act as a cocoon when cell is damaged
3. anchor ion channel proteins
4. form the nuclear lamina

Front 28

G1 phase

Back 28

12-36 hours

Front 29

S-phase

Back 29

8-10 hours

Front 30

G2-phase

Back 30

1-4 hours

Front 31

H&E Stain - nucleus

Back 31

dark blue/purple

Front 32

H&E Stain - cytoplasm

Back 32

pink

Front 33

H&E Stain - mitochondria

Back 33

pink

Front 34

H&E Stain - RER/ribosomes

Back 34

blue

Front 35

H&E Stain - membranes, golgi, SER

Back 35

do not stain

Front 36

H&E Stain - collagen

Back 36

pink

Front 37

H&E Stain - glucosaminoglycans

Back 37

blue

Front 38

Microvilli and stereocilia

Back 38

specialized for absorption; contain a core of actin filaments

Front 39

Cilia

Back 39

have axoneme (9 doublets around central pair) core; have centriole, or basal body, (9 triplets, no central pair) at base, which stains with H&E

Front 40

Where are the secretory vesicles in exocrine secretory cells?

Back 40

apical part

Front 41

Where are the secretory vesicles in endocrine secretory cells?

Back 41

basolateral part

Front 42

Zonula occludens or tight junctions

Back 42

separate the apical from the basolateral surface; forms a belt around the cell

Front 43

Zonula adherens or adherens junction

Back 43

connects the actin cytoskeleton of adjacent cells; associated proteins are members of the cadherin family; forms a belt around the cell

Front 44

Desmosome or macula adherens

Back 44

connects the intermediate filament cytoskeleton of adjacent cells; form "spot welds"; provide tensile strength to keep cells from being torn apart

Front 45

Terminal bar

Back 45

seen on light microscope; consists of zonula occludens, zonula adherens, and desmosomes

Front 46

Gap junctions

Back 46

connect the cytoplasm of adjacent cells; the channel is called a connexon

Front 47

Basal lamina

Back 47

secreted by epithelium and composed of collagen IV, laminin, and proteoglycans; Two layers:
1. lamina rara - lightly staining
2. lamina densa - darkly staining

Front 48

Basement membrane

Back 48

formed by epithelium, basal lamina, and adjacent connective tissue

Front 49

Focal adhesions

Back 49

attach actin cytoskeleton to the basal lamina; proteins are members of the integrin family

Front 50

Hemidesmosomes

Back 50

attach intermediate filament cytoskeleton to the basal lamina; proteins are members of the integrin family

Front 51

Epithelia specialized for secretion of proteins have prominent...

Back 51

RER, Golgi, Secretory vesicles

Front 52

Epithelia specialized for secretion of lipids (such as steroid hormones) have prominent...

Back 52

SER, Mitochondria, Lipid droplets

Front 53

Merocrine or eccrine secretion

Back 53

secrete water-soluble macromolecules; secretory vesicles fuse with apical membrane and release contents into extracellular space; Two types:
1. Serous glands - proteins or glycoproteins
2. Mucous - proteoglycans

Front 54

Apocrine secretion

Back 54

secrete lipid-soluble macromolecules by pinching off part of the plasma membrane, so secretion includes secretory vesicle, cytoplasm, and portion of plasma membrane; e.g., mammary glands and melanin by melanocytes

Front 55

Holocrine secretion

Back 55

entire secretory cell is sloughed from epithelium; e.g., sebaceous glands of the skin

Front 56

Functions of connective tissue

Back 56

1. Provide structural support
2. Storage of metabolites
3. Defense and protection (immune, inflammatory, allergic)
4. Repair other tissues

Front 57

Type I Collagen

Back 57

forms fibrils, fibers, and bundles
found in dermis of skin, tendons, ligaments, fascia, bone

Front 58

Type II Collagen

Back 58

forms fibrils
found in cartilage

Front 59

Type III Collagen

Back 59

forms fibrils and fibers (reticular fibers)

Front 60

Type IV Collagen

Back 60

does not form fibrils
found in basal lamina as a sheet-like meshwork of beaded filaments

Front 61

Ehlers-Danlos Syndrome (EDS)

Back 61

due to defective collagen fibers;
Symptoms include skin hyperelasticity, loose, unstable joints that are prompt to dislocation, low muscle tone/muscle weakness, osteopenia (low bone density), and deformities of spine

Front 62

Elastic fibers

Back 62

1. Elastin - responsible for the elasticity; contains hydrophopic domain; cross-linked by covalent bonds
2. Fibrillin - glycoprotein that forms thin microfibrils that surround the developing elastic fibers and provide substrate for their assembly

Front 63

Marfan's syndrome

Back 63

mutation if fibrillin gene which results in cardiovascular, skeletal, and ocular defects including MITRAL VLAVE PROLAPSE, rupture of elastic arteries, and arachnodactyly

Front 64

Glycosaminoglycans (GAGs)

Back 64

ong-chain, unbranched, highly negatively charged polysaccharides
i.e., chondroitin sulfate, dermatan sulfate, keratan sulfate, heparane sulfate, and hyaluronic acid (different because does not contain sulfate and doesn't form proteoglycans)

Front 65

Multiadhesive glycoproteins

Back 65

serve as cross-links between collagen, ECM, and cells; Two types:
1. Fibronectin - more abundant; interact with types I, II, and III collagen, GAGs, fibrin, integrin, and others
2. Laminin - present in basement membrane; binds type IV collagen, integrins, and others

Front 66

Functions of macrophages

Back 66

1. Phagocytosis
2. Present antigens
3. Produce cytokines that activate the immune system

Front 67

Mononuclear phagocytic sysetm - histiocytes

Back 67

connective tissue

Front 68

Mononuclear phagocytic sysetm - alveolar macrophages

Back 68

lung

Front 69

Mononuclear phagocytic sysetm - Kupffer cells

Back 69

liver

Front 70

Mononuclear phagocytic sysetm - osteoclasts

Back 70

bone

Front 71

Mononuclear phagocytic sysetm - Langerhans cells

Back 71

skin

Front 72

Mononuclear phagocytic sysetm - dendritic cells

Back 72

lymphoid organs

Front 73

Mononuclear phagocytic sysetm - microglial cells

Back 73

central nervous system

Front 74

Degranulation of a mast cell causes...

Back 74

1. Histamine causes vasodilation and increases vascular permeability
2. Histamine causes bronchoconstriction and increased mucous production
3. Chemotactic mediators attract white blood cells, eosinophils and neutrophils

Front 75

Plasma cells

Back 75

anti-body producing cells derived from B-lymphocytes

Front 76

Lymphocytes

Back 76

have a round, dark, heterochromatic nucleus; Their main function is production of antibodies and regulation of immune response

Front 77

Monocytes

Back 77

phagocytic cells that are precursors for tissue macrophages; they are characterized by a kidney-shaped nucleus

Front 78

Neutrophils

Back 78

phagocytic cells aimed at bacteria; They have an elongated, segmented, multi-lobed nucleus

Front 79

Eosinophils

Back 79

involved in reaction to paracytic infestations; they are characterized by the presence of intensely staining eosinophilic granules and a bilobed nucleus

Front 80

Basophils

Back 80

rare in blood and connective tissue; they are involved in the allergic response; they have a bilobed nucleus and large number of basophilic granules in the cytoplasm

Front 81

Embryonic connective tissue

Back 81

1. mesenchyme - composed of mesenchymal cells, few collagen/reticular fibers, and abundant ground substance
2. Mucous connective tissue - only in umbilical cord, large amounts of hyaluronic acid, few collagen/reticular fibers; a.k.a. Wharton's jelly

Front 82

Loose connective tissue

Back 82

highly cellular (lots of transient cells); sparse collagen type I fibers, no bundles; located in lamina propria of intestine and surrounds blood and lymphatic vessels and nerves

Front 83

Liposarcoma

Back 83

a malignant tumor derived from the precursors of adipocytes

Front 84

Lipoma

Back 84

a benign tumor derived from adipocytes

Front 85

Hibernoma

Back 85

a rare tumor derived from multilocular adipocytes

Front 86

reticular connective tissue

Back 86

a loose connective tissue found in the stroma of lymphoid organs

Front 87

chondrosarcoma

Back 87

slow-growing tumor with slight male predominancy; most common in pelvis, proximal femur, and proximal humerus; malignant cells with abundant cartilaginous matrix

Front 88

Howship's lacuna

Back 88

the depression in the bone matrix etched by osteoclasts

Front 89

Osteosarcoma

Back 89

malignant proliferation of osteoblasts; common in teenagers in distal femur, proximal tibia, and proximal humerus

Front 90

Osteoid osteoma

Back 90

small benign tumor that occurs anywhere in the appendicular skeleton or spine and causes acute night pains

Front 91

Paget's disease

Back 91

results in large and deformed bones; new bone is more fragile and prone to fractures