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Flashcards in Histo exam 1 Deck (83):
1

What is cardiolipin?

In inner mito. membrane, makes membrane impermeable to electrons and protons!

2

adherens junction

anchors ACTIN by CATENIN and VINCULIN; Ca2+ dependent actions between cells through CADHERIN PROTEINS

3

peroxisome?

use CATALASE to break down long chain fatty acids to acetyl coa and then to hydrogen peroxide, replicate by fission

4

intermediate filament for epithelial cell?

cytokeratins

5

phospholipid polar region made up of:

+ choline and - phosphate

6

cholesterol forms microdomains called:

lipid rafts- lots of concentrated cholesterol important for cell to cell interactions

7

glycolipids- disease

Tay Sachs- defect in ganglioside metabolism, missing hexosaminidase, affects CNS neurons

8

how does the glycocalyx protect the cell?

have as strong negative charge on outer surface to block infection

9

movement of macromolecules and particulate matter across cell membrane is called:

endocytosis and exocytosis

10

3 types of endocytosis:

pinocytosis (drinking)
receptor mediated endo.
phagocytosis- eat big stuff

11

how does pinocytosis work?

bulk fluid uptake into CLATHRIN coated vesicles, vesicles pinch off by DYNAMIN

12

how does receptor-mediated endo. work?

LDL receptor on membrane pick up LDL molecules, fall into clathrin coated pit, pinch into a vesicle, acidity causes receptor and ligand to unattach, dealt with by lysosome

13

how does phagocytosis work?

NOT CLATHRIN DRIVEN! caused by changes in active cytoplasm- done by macrophages and neutrophils, rearrange actin cytoskeleton, phagosome, stuff binds to receptors on cell membrane

14

2 types of exocytosis

1. regulated pathway: controlled by specific stimulus (hormones cause calcium to trigger zymogen granules released to small intestine)
2. constitutive pathway: replaces membranes and membrane proteins as well as secreting materials synthesized by the cell (mucous secretion by goblet cells)

15

RER : SER

flattened sacs: tubes

16

SER function?

membrane synthesis, make steroid hormones, Ca homeostasis (sarcoplasmic reticulum), detox of lipid soluble drugs, metabolic waste and ingested toxins by cytochrome p450 system

17

rer function?

makes integral and secreted proteins, 1st site of post-translational modification

18

ribosome size? translation?

12nm wide, 25nm long, signal sequence binds to signal recognition particle which binds to SRP receptor on RER, keeps translating, signal peptidase cuts off signal sequence

19

golgi functioning...

trans face: sort/packages stuff into:
1. non-clathrin coated vesicle to PM
2. clathrin coated vesicle
3. lys. enzymes for the lysosome gets mannose6p since lysosome has a m6p receptor, also has clathrin coating

20

lysosome size, function

<1 micrometer, irregular shape, have acid hydrolases, come from trans golgi network,primary lysosome + late endosome = secondary lysosome

21

lysosomes and osteoclasts

lysosomes release hydrolytic enzymes in extracellular space that osteoclasts use to do bone remodeling

22

autophagy and heterophagy

thing that eventually combines with lysosome is from cell (autophagy) or outside cell (like a bacteria that was phagocytized) heterophagy

23

what are lipofuscin residual bodies?

stuff that can't get let out are suck there, build up in cell. have secondary lysosome action

24

pompe lysosomal storage disorder?

no glucosidase, accumulate glycogen, bad for heart

25

hurler lysosome storage disorder?

no L-Iduronidase, accumulate dermatan sulfate, affect skeletal system

26

Niemann-Pick lysosomal storage disorder?

no sphingomyelinase, accumulate sphingomyelin, affect CNS oligodendrocytes

27

peroxisome function?

.2 micrometer, fission, aka microbodies
have CATALASE and other oxidative enzymes to break down long fatty acid chain to acetyl coa to hydrogen peroxide

28

mitochondria info?

.5 micrometer x 7 micrometer, make ATP, slef replicate

29

mito. matrix?

has krebs cycle enzymes, matrix granules important for binding Ca2+, circular dna and own mRNA, tRNA, ribosomes

30

mito. inner membrane

ATP synthase protein complex, ETC enzymes, lots of CARDIOLIPIN- makes membrane impermeable to electrons and protons

31

what stuff counts as INCLUSIONs?

glycogen granules, lipid droplets, pigment granules (lipfuscin, melanin), crystalline inclusions

32

nuclear pore complex?

allows free passage of ions/molecules < 60kDa
bidirectional ACTIVE transport of big stuff
-nuclear localization (importin) signals
-nuclear export signals (exportin)

33

chromatin 2 types:

euchromatin: <30 nm, dispersed, transcriptionally active
heterochromatin: condensed, inactive

34

nucleolus

where rRNA is made, ribsome subunits assembled, VERY acidic/basophilic

35

nuclear envelope

inner membrane supported by nuclear lamin A,B,C
outer membrane continuous with RER

36

microfilament fuction

actin, maintain cell shape, cell cortex, cytoplasmic streamingm cell motility (treadmilling to make pseudopodia), muscle contraction, cell division (make cleavage furrow), add at + end, decrease at - end

37

intermediate filaments

form nuclear lamina, anchor nucleus and other organelles, tension bearing elements, structurally homologous but biochemically distinct

38

EPIDERMOLYSIS bullosa?

cytokeratin intermediate filaments let epidermal cells/skin resist stress, mutation in CYTOKERATIN --> fragile skin, blistering

39

microtubules function:

cell shape (compression resisting girder), organelle movement (kinesin, dyenin), mitotic spindle, cilia/ flagella

40

microtubule structure

long straight rigid: alpha/beta tubulin dimer
minus end in microtubule organizing center (MTOC), polymerize and depolymerize at (+) end

41

kinesin and dynein

ATPases: transport membrane bound organelles along microtubules
KINESIS, anterograde: - -> +
DYNEIN, retrograde + -> -

42

Why have a PAS stain of microvilli?

has lots of carbs, glycocalyx, actin based structure

43

microvilli size? function

1-2 micrometer long, 80 nm diameter, actin cytoskeleton, non-motile, increase SA

44

cilia size? function? structure?

8-10 micrometer long, .25 micrometer diameter,
move fluids over cell surface, anchor to basal body, DYNEIN-dependent hydrolysis of ATP, AXONEME- microtubulues in 9+2 organization

45

Kartengener's syndrome?

no dynein arms in cilia, respiratory problems, mucus pool at bottom of lungs, sperm problems

46

is stereocilia real cilia?

NO, long microvilli, in testes and hair cells

47

is kinocilia real cilia?

YES, non-motile cilia, 9+0 axoneme, hair cells

48

zonula occludens

tight junction, complex of OCCLUDIN and CLAUDIN, prevent water soluble molecule movement btw. cells and movement of integral proteins
--> bad ones lead to leaky gut syndrome

49

desmosomes

adhesive by DESMOGLEIN and DESMOPLAKIN, intermediate filaments anchor to it

50

gap junction

CONNEXONS channels made of 6 connexin subunits, let ions/small molecules pass btw. cells, couple cells electronically and metobolically

51

basement membrane and cell-to-extracellular matrix connections

hemidesmosome--> basal lamina (lamina lucida, lamina densa) -> reticular fibers
LAMININ, TYPE 4 COLLAGEN, ENTACTIN, PERLECAN
for support, filtration, adhesion

52

integrins

transmembrane protein (alpha/beta heterodimer), couple to actin cytoskeleton, alpha chain mediates adhesion by binding to short recognition sequences on ECM molecules like LAMININ, FIBRONECTIN, COLLAGEN
-important in SIGNAL TRANSDUCTION

53

pemphigus disease?

autoimmune disease against parts of desmosome/hemidesmosome
-epidermal blistering and loss of extracellular fluid

54

Alport's syndrome

inherit defect in type 4 collagen, filtration problem so blood goes in urine (hematuria)

55

cell cycle control: extrinsic factors

nutrients, growth factors

56

cell cycle control: intrinsic factors

cell senescence, accelerated aging
Werner's- mutation in gene encoding DNA helicase
Progeria (Hutchinson-Gilford) - mutation in intermediate filament that lines nuclear envelope

57

cyclins in interphase

G1 -> S: cyclin D and E
S->G2: cyclin A
G2-> M: cyclin B

58

prophase

chromosome condense, kinetochore go on centromeres, centromere go to poles, spindles start to form

59

prometaphase

nuclear envelope breaks down, microtubules attach to kinetochores, chromosomes begin to migrate

60

anaphase

sister chrom. separate, cleave furrow begins to form

61

telophase

spindle microtubules begin to depolymerize, nuclear envelope forms around daughter nuclei, chromosomes begin to decondense and nucleoli form, cleavage furrow deepns

62

which cell cycle anti cancer drugs disrupt mitotic spindle formation?

vincristine/colchicine destabilize microtubules

taxol stabilize microtubules to prevent from moving

63

which anti cancer/cell cycle drug inhibits DNA synthesis?

5-fluorouracil/methotraxate block formation of deoxynucleotides

cytosine arabinoside- analog of cytosine that blocks DNA replication

64

What are the 5 steps of meiotic prophase?

1. leptotene- condense
2. zygotene- pair
3. pachytene- recombination
4. diplotene- oocyte dormant til puberty here, coil
5. diakinesis- recondense, nucleolus and nuclear envelop disappear

65

trisomy 21

nondisjunction in 1st meiosis, homologues didn't get pulled apart

66

What is the giesma stain?

chromosome banding in karyotype- general organization of genes within each chromosome

67

chronic myelogenous leukemia- philadelphia chromosome?

dna between chromosome 22 and 9 get swapped, wild replication of cells in bone marrow

68

how long does apoptosis take?

20 minutes

69

physiological examples of apoptosis

embryo development (delete webs)
cell turnover (intestinal crypt)
t-cell conal deletion
normal involutional process (breast, ovary, endometrium)
atrophic processes (prostate)

70

apoptosis examples in pathology

atophic process (kidney, liver)
viral (HIV)
immune-mediated cell killing (rejection, graft vs. host)
cellular injury (radiation, chemo, toxin)

71

disease and increased apoptosis

aids, neurogenerative disorder (parkinson, alzheimer, amytrophic lateral sclerosis, retinitis pigmentosa, cerebellar degeneration), aplastic anemia, alcohol toxin liver disease, ischemic (heart injuries)

HEART AND BRAIN

72

disease with inhibition of apoptosis

cancer, autoimmune disorders, viral infections (herpes, pox, adenovirus)

73

mechanisms of apoptosis

1. organelle dysfunction (intrinsic)
2. DNA damage
3. death receptor activation (extrinsic)
4. abnormal protein folding/ accumulation

74

apoptosis: organelle messed up!- intrinsic

BAX activated, pokes hole in mitochondria membrane, AIF, Cyt. C, APAF-1 come out --> CASPASES --> nuclear fragmentation

75

extrinsic apoptosis pathway

cell death receptor activated at cell membrane, caspase cascade leads to apoptosis

76

necrosis affected diseases

neurodegenerative, cerebral ischemia, heart disease

77

what are triggers of necrosis?

acute energy depletion, trauma, harsh environment, extrensive DNA damage

78

necrosis mechanisms

bother ion homeostasis (increase Ca, Na, Mg, Zn, acidosis, degenerins for animals)

protein degradation- lysosomes (cathepsin, hydrolase), CALPAINS, caspase

79

autophagy mechanism

autophagic vacuoles accumulate in cells, type 2 cell death (lysosomal)

autophagosome (membrane bound structure with damaged organelle) merge with lysosome and gets digested

80

autophagy occurs in

development, differentiation, tissue remodeling, cancer, liver disease, muscle disease, neurogenerative disease, infection

81

preventing cell death

Ca2+ blockers, caspase inhibitor, protease inhibitor, glutamate receptor antagonist (memantine), growth factors (BDNF), cytokines, antioxidants

FUTURE: gene therapy (bcl2 gene transfer), natural caspase inhibitor, understand hibernation, anti-apoptotic molecules (anti-p53)

82

cell death regulators

p53, bcl2, cell cycle genes, fas ligand, cytokine, proteosome, mitochondria, lysosome, calcium

83

cell death effectors

caspase, cytochrome c, apaf1, DFF, lamin, gelsolin, calpain, cathespins, autophagosome