Cytoplasm And Organelles

Front 1

What are ribophorins?

Back 1

The RER membrane receptors which bind to large ribosomal subunits

Front 2

What are annulate lamellae?

Back 2

Parallel stacks of membranes that resemble the n uclear envelope. Continous with RER

Front 3

Uncoupled oxidation from phosphorylation

Back 3

Conformational change in mitochondria due to uncoupling of oxidation from phosphorylation.

Results in condensed mitochondria:
present in brown fat cells

Swollen mitochondria (due to calcium, phosphate, and thyroxine) can also result in uncoupling.

Front 4

Golgi Apparatus structures (4x)

Back 4

1. Cis face (cis golgi network: CGN): located at the site of Golgi facing ER

2. Medial compartment: composed of few cisternae lying b/t cis and trans faces

3. Trans golgi: golgi complex facing vacuoles and secretory granules

4. trans golgi network (TGN): apart from trans face, sorts proteins for final destinations

Front 5

ERG intermediate compartment

Back 5

Way station with enzymes distinct from RER and Golgi. Segregation of anterograde vs retrograde transport

Front 6

Clathrin coated vesicles. Structure and molecules.

Back 6

Structure: cagelike lattice around vessicles, adaptins are part of coat; capture cargo receptors and help establish vesicle curvature. Dynamin helps pinch off vesicles

Front 7

Coatomer-coated vesicles (COP). Assembly.

Back 7

Assembly dependent on ADP-ribosylation factor (ARF) which utilizes GTP

Front 8

Coatomer-coated vesicle function.

Back 8

SNARES recognize COP and facilliate docking.

COP I: retrograde transport (to rER)
COP II: anterograde transport (form rER)

Front 9

Lysosome. Formation and function

Back 9

Formation: Sequestered material fuses with late endosome.

Early endosome: proton pumps which give low acidity

Late endosomes: contain lysosomal hydrolase and lysosomal membrane proteins.

Fusion of sequestered material with late endosome and subsequent degradation = lysosome

Front 10

Organelles that divide by fission (2)

Back 10

Mitochondria and peroxisomes

Front 11

Centrosomes. Structure..

Back 11

Two centrioles in pericentriolar material (9 + 0 axoneme pattern).

Self-duplicate in S phase by procentriole forming at right angles to itself.

Front 12

Centrosome. Function (4x)

Back 12

1. MTOC
2. Periceintriolar cloud has gamma tubulin which serves as starting point of polymerization of one microtubule.
3. Centrosome itself duplicated during interphase; forms mitotic spindle.

4. Form basal bodies (axoneme of cilia and flagella)

Front 13

Microtubule proteins (3x)

Back 13

1. MAP: microtubule-associated proteins (MAPs) which stabilize mts.

2. Kinesin: moves cargo towards plus end

3. Dynein: moves towards minus end (inward)

Front 14

Microtubule vs Actin

Back 14

Microtubule: polarity, alpha and beta tubulin subunits, GTP binded to alpha-beta unit

Actin: polarity, +/- barbed ends, ATP converts G to F actin

Front 15

crinophagy

Back 15

fusion of hormone secretory granules with lysosomes and subsequent digestion of them

used to remove excess number of secretory granules w/i the cell

Front 16

lysosomal storage diseases (3)

Back 16

1. Tay Sach's Disease: deficiency of hexosaminidase A; accumulation fo GM2 gangliosides

2. Hurler syndrome: def. in GAG degradation lysosomal enzyme; accumulation of GAGs in heart, brain, liver and other organs

3. Glycogen storage diseases: hereditary defect in any enzyme involved in syn/degradation of glycogen; glycogen accumulation in organs.

Front 17

familial hypercholesterolemia

Back 17

inherited genetic defect of cells to take in cholesterol

LDL unable to bind to clathrin coated pits/faulty LDL receptors

Front 18

peroxisomal diseases (2)

Back 18

1. Zellweger syndrome: normal peroxisomes are absent; infants have neurological disorders

2. Adrenoleukodystrophy: inability of peroxisomes to metabolize fatty acids

Front 19

Vesicle movement (3x)

Back 19

1. COP I: retrograde (towards the ER)

2. COP II: anterograde (away from ER) and plasma membrane proteins

3. Clathrin-coated: recovery of exocytosis material, lysosomal proteins to late endosome (from TGN), or secretory proteins (TGN)