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Flashcards in Exam 2 Deck (128):
1

What does I cell disease involve, and what organelle is responsible

Accumulation of inclusion bodies inside cell
Golgi apparatus

2

What is the Golgi apparatus part of

The rough er

3

What is the function of the GA

Packaging and processing and modification of proteins and glycolipids

4

What is the general progression of the GA

Cis-medial-trans-trans Golgi network(TGN)

5

Are ribosomes found in the GA

No, there is no protein synthesis here

6

What are embedded on the cis-facing side of the GA

Glycosyltransferase
Sorting proteins

7

What is the function of glycosyltransferase

Addition or modification of sugar chains to create glyco-lipid/protein

8

What are the major functions of the GA

Lysosome formation
Secretory vesicle formation
Plasma membrane renewal

9

Where are hydrolase enzymes created

The rough er

10

What are the steps to sequestering the hydrolase enzymes after the rough er has created them

1)Mannose chain added in er
2)Transported to cis side GA
3)IN cis, mannose is capped with phosphate by glucose phosphotransferase
4)moved to TGN gathered by mannose-6 phosphate receptors and sent to lysosome

11

Which organelle exhibits CURL properties

The Golgi when sending hydrolase to lysosomes

12

If a vesicle does not have a phosphorylated mannose flag where is it destined for?

Plasma membrane, and the contents will be released to the ECM

13

What are the two types of exocytosis

Constitutive
Regulated

14

What is constitutive exocytosis

The default path for vesicles with no delay

15

What is regulated exocytosis

Vesicle is bound to the cytoskeleton and is not releases until the cell is stimulated

16

What are the causes of I cell disease

Failure to synthesize glucosamine phosphotransferase causing lysosomal enzymes to be excreted into the ECM and anything brought into the cell to not be broken down causing accumulation of inclusion bodies

17

I cell disease is a disease of what organelle

The Golgi apparatus

18

What is a hydrolase and what is its function

Hydrolase are digestive enzymes found in lysosomes
They cleave molecules by adding water

19

What is a primary lysosome

Newly formed and inactive lysosome with a homogenous interior

20

What is a secondary lysosome

A primary that has fused with an endosome and has a heterogenous interior making it active

21

How does the CURL function in lysosomes

Similar to endocytosis, the membrane receptors that cause the binding of the primary and the endosome

22

What happens to secondary lysosomes once they have absorbed materials to be digested

The digested materials leak out of the lysosome and the lysosome involutes into a multivesicular body and disappears

23

If a lysosome cannot digest a material what happens

The small vesicle will remain permanently and it's called an residual body

24

What is autophagy

Self digestion, part of the normal turnover of organelles, and receptors located on the plasma membrane.

25

What is heterophagy

Digestion of foreign materials

26

What are external operations

Extracellular digestion,
Can be from osteoclasts, or neutrophilic attack in defense

27

What is the importance of the lysosome having so am my different hydrolytic enzymes

So that it can digest any potential substrates

28

What are the symptoms of Tay-Sachs disease

Gradual onset of retarded neurological development
Increased head size
Cerebral and macular degeneration
Death by two years
Many lipid containing lysosomes

29

What is the causes of Tay- Sachs disease

The accumulation of lipids in cells due to missing Hex A enzyme

30

What are the symptoms of myoclonic epilepsy with ragged red fibers

Myoclonus ( shock like contractions of some muscles)
Muscle weakness
Epilepsy
Gradually increasing levels of brain dysfunction
Deterioration of skeletal muscles

31

What muscle fibers does MERRF affect

Type 1 fibers only (dependent on oxidative phosphorylation)

32

How is MERRF passed on

Through maternal inheritance

33

What is the major laboratory finding associated with MERRF

Torn muscle fibers, with bright red staining

34

What dictates the number if mitochondria present in a cell

Activity of the cell and its need for ATP

35

What is located on the outer mito membrane

Porins, allow for free passage of many different molecules.

36

What is the structure of the inner mito membrane

Many folds called cristae containing proteins needed for the electron transport system.

37

What important molecule is located in the inner mito membrane

Cardiolipin, causes the membrane to be highly impermeable to ions especially H+

38

What accumulates in the inner membrane space of the mito

Protons

39

What is filling the interior of the mito, specifically in the IMM

The matrix

40

What is the chemiosmotic coupling hypothesis

Protons pumped out of the matrix into the intermembrane space against there gradient, creating a proton motive force which moves back through the membrane bringing e- with them creating ATP in the ATP synthase

41

Where does glycolysis happen

The cytoplasm, it's the conversion of glucose to pyruvate

42

Where does the Krebs cycle happen

In the matrix creates electrons and protons needed to create gradient

43

Where does the electron transport chain happen

In/on the inner mito membrane, pumps the protons across the membrane creating gradient needed.

44

What is the IMM re-entry protein

ATP synthetase (F1 Particle)

45

What are the products of glycolysis

Pyruvate ( converted to acetyl coA)
Small amount of ATP

46

What are the product of the Krebs cycle

Electrons
Protons
Both received by NAD becoming NADH

47

What are the ETS products

ATP and h2o

48

What molecule creates the ATP in the ETS

ATP synthetase or f1 particle or complex 5 protein

49

What is another name for the complex 1 protein

NADH dehydrogenase

50

What are the reactants going into the mitochondria

ADP, oxygen, and hpo4

51

What are the products of the mitochondria

ATP ,co2 , h2o

52

What is MERRP a disease of and what are the causes

Disease of the mitochondria
Muscles and neurons that are dependent on ATP deteriorate
High NADH levels because of failure of the ETS

53

What are the symptoms of katagener syndrome

Chronic sinusitis
Chronic headaches
Situs Inversus viscerum
Males are infertile

54

What are the functions of the cytoskeleton

Maintain cell shape
Motility
Contraction
Transport through the cytoplasm
Organize the cytoplasm

55

What molecules make up the thin filament in muscle

Actin+troponin+tropomyosin

56

What makes a string of G-actin

G-actin(globular) + f-actin(filamentous)

57

True/false: myosin is an enzyme

True head region has the ability to walk on actin with ATP

58

What occurs when the myosin head binds near the g-actin

The power stroke

59

What is the rigor complex

When calcium lands tropomyosin moves out of the way allowing myosin to bind actin in the cocked position

60

What is the ultimate control of contraction

Temporarily opening the calcium channels

61

What is a ryanodine receptor

Protein that when signaled by neurotransmitter it will release calcium from voltage gated channels
Located in the SER

62

What happens in a low calcium environment

Actin is turned "off" by allowing troponin to move tropomyosin to a position that myosin cannot walk

63

When calcium is present what happens in a muscle cell

Actin is on by inducing troponin to bind to tropomyosin moving it exposing g actin

64

What regulates the sliding filament theory

Calcium

65

What makes up the contractile ring of a cleavage furrow

Actin and myosin

66

What filaments make up the z line

Desmin

67

What filaments are found in the interior of micro villi

Mostly actin and some myosin anchoring to the terminal web

68

How to adhering junctions, spectrin stay anchored to the cell

By anchoring to the actin fibers

69

What are the intermediate fiber types

Keratin, desmin, vimentin, neurofilaments

70

What fiber is a major player in the desmosome (skin)

Keratin

71

What filaments are found in the a band

Myosin, actin (sort of),

72

What filaments are found in the I band

Actin and desmin

73

What does a cadherin attach to

Other cells

74

What does an integrin attach to

The ECM protein

75

Which fibers are used in endocytosis and exocytosis

Actin and myosin

76

What is a desmin fiber

The fibers that make up the z lines of the muscles cells

77

What is a neurofilament

Structural protein in a neuron helping it to maintain long projections

78

What is the purpose of intermediate filaments

To maintain integrity, ie structural

79

What is a microtubule made of

Tubulin

80

Where are the microtubules formed

Made in the microtubule organizing center

81

What is the arrangement of the centriole

9+0 arrangement

82

How does movement occur on the microtubule

Kinesin, and dynein

83

What functions are microtubules seen in

Axoplasmic flow
Exocytosis
Spindle apparatus
Movement of cilium and flagellum(axoneme)

84

What is the arrangement of an axoneme

9+2

85

What is an axoneme anchored by

The basal body, which has a 9+0

86

What would a slower moving cell use for movement

Steady actin myosin system

87

What would a fast moving cell move

Ameboid movement
Chemotaxis, lamellopodium, cytoskeleton anchoring and movement, plasma membrane recycling

88

What is chemotaxis

Reception of an attractant molecule, causing cell to synthesize cytoskeleton in that direction

89

How is a lamellopodium

Actin pulled into the area by myosin and more membrane is added to the growing side

90

What is diapedesis

Defender cell departs from the bloodstream

91

What is katagener syndrome a disease of

Disease of the cytoskeleton
No axonemal function, so cilia and flagella fail.

92

How many membranes make up the nucleus

2, inner and outer

93

What ais the INM connected to

Intermediate microfilaments, called the nuclear laminate, providing support for the nuclear envelope and chromatin

94

What is the ONM continuous with

The rough er, there may be ribosomes here that create proteins destined for the nuclea envelope or the perk nuclear space

95

What is are between the INM and ONM called

The peri nuclear space, often continuous with the rough ER cisternae

96

How is nuclear pore number and cell activity linked

The more transcriptionally active, the more nuclear pores

97

What is the nuclear matrix

Web of proteins that provide nuclear shape, likely serving as scaffolding for DNA transcription

98

What are the functions of histones

Wind of DNA and form nucleosomes

99

What is euchromatin

Dispersed and transcriptionally active DNA, cannot be seen in microscope

100

What is heterochromatin

Highly condensed and transcriptionally inactive DNA

101

Where is heterochromatin usually located

Periphery of nucleus but not covering pores

102

What is the difference between constitutive and facultative heterochromatin

Constitutive: always condensed ie never used
Facultative: can be dispersed for use as needed

103

What is the nucleolus made of

Special kind of chromatin
There may be more than one nucleolus depending on how transcriptionally active a cell is

104

What is the more precise process of cellular division

Karyokinesis
Cytokinesis is somewhat haphazard

105

When does the cell cycle begin, and when does it end

Starts: when cell is born
Ends: the moment it divides into daughter cells

106

What proteins control the cell cycle

Cyclin dependent kinases (CDK), cyclins, and mitogens

107

What does interphase consist of

G1, S, and G2 phases

108

Which phase does the cell spend most of its life in

G1, can be referred to as G0 phase is the cell will never divide

109

What occurs in G1 phase

Cellular growth

110

What occurs in S phase

DNA synthesis, and duplication phase

111

What occurs in G2 phase

Another round of cellular growth in preparation for division, much shorter than G1 phase

112

What is the slowest phase of M phase

Prophase

113

How are the sister chromatids held together

2 protein kinetechore

114

What are the three kinds of microtubules of the spindle apparatus

Astral
Kinetochore
Polar

115

How do the astral microtubules function

Spray out from the centrosome, to anchor the spindle

116

What is the function of the kinetochore microtubules

Connect centrosome to kinetochore, pulling chromatids apart

117

What is the function of the polar microtubules

From centrosome to centrosome, pushing each other apart

118

What might late metaphase be referred to as

Pro metaphase

119

During which phase do the spindles connect to the kinetochore

Metaphase

120

What occurs following telophase

Chromosome disappears
Nuclear envelope reforms
Nucleolus reforms
Mitotic spindle disassembles
CYTOKINESIS

121

How cancer cells develop

By escaping the tightly regulated cell cycle, growing in absence of stimulation

122

What is the mitotic index of a normal cell

.05 (5%)

123

What is the mitotic index of a cancer cell

.1-.2 (10-20%)

124

What are some characteristics of cancer cells

Lacking contact inhibition
Large nuclei
High mitotic index

125

What are the genes that directly promote or inhibit cell division

Tumor suppressor genes
Oncogenes

126

What are the symptoms of Burkitss Lymphoma

Cancer of lymph nodes, that rapidly spreads to nervous system blood and bone marrow
Lab finding: chromosomal translocations

127

What are the causes of Burkitts lymphoma

Translocation a of chromosome 8 and 14 causing myc oncogene to be stimulated when b lymphocytes are stimulated in response to infection.

128

What is Burkitts lymphoma a disease of

The nucleus- it's a corruption of the DNA specifically