PRIN 4 Organization of the Cell

Question 1

diastrase

Answer 1

enzyme that digests glycogen

*was used to clear the liver biopsy sample of glycogen. As a result, PAS allows visualization of the glycosylated granules of alpha1-proteinase inhibitor that was defective and trapped in the rER

Question 2

Plasma vs Serum

Answer 2

PLASMA: contains all clotting factors
SERUM: after clotting factors have been removed

Question 3

What is “Alpha-1 antitrypsin?”

Answer 3

• protein that is produced mostly in the liver

* protects the lungs from neutrophil elastase

Question 4

What is “Neutrophil elastase?”

Answer 4

• enzyme that digests damaged or aging cells and bacteria in the lungs
• regulated by alpha 1 proteinase inhibitor

Question 5

What is the result of alpha1-proteinase inhibitor def?

Answer 5

Elastase digests lung tissue in an uncontrolled fashion and leads to emphysema
***HIGH risk of lung disease

Question 6

How is Kartageners Syndrome inherited?

Answer 6

Autosomal recessive mutation

Question 7

What causes Kartageners Syndrome?

Answer 7

loss of dynein arms: cilia don’t work properly

Question 8

Clinical Manifestation of Kartageners Syndrome:

Answer 8

(1) recurrent upper resp infections
(2) male infertility
(3) ectopic preg
(4) organs on wrong side

Question 9

What causes CF?

Answer 9

Cystic Fibrosus
Autosomal recessive (CFTR gene)
*Defect in ABC transporter (ATP-binding cassette) results in faulty transmembrane protein that is an epithelial Cl- channel

Question 10

What happens to the faulty CFTR gene in CF?

Answer 10

gets degraded by proteosome

Question 11

Newly made proteins leave the rER and go where?

Answer 11

cis face of golgi via vesicle with COP2 coat

Question 12

How do vesicles get BACK to the golgi?

Answer 12

via COP1 coat

Question 13

What is the “H-antigen?”

Answer 13

*protein that is expressed on RBC membrane surfaces

Question 14

What is glyco-syl-transferase?

Answer 14

• protein that modifies H-antigen on RBC surfaces

* exists in 3 forms depending on the 3 allele forms: ABO

Question 15

What does the O allele result in?

Answer 15

encodes for an inactive glyco-syl-transferase leaving the H antigen unmodified

Question 16

Example of Regulated Secretion

Answer 16

(1) Synaptic Transmission
(2) Mast Cell
(3) Salivary Glands

Question 17

How is exocytosis regulated in Synaptic Transmission?

Answer 17

V-SNARE on vesicle interacts with T-SNARE on target

Question 18

How do tetanus toxins disrupt synaptic transmission?

Answer 18

cleave SNARES preventing interaction and release of contents into synaptic cleft

Question 19

How does hay fever result in allergies?

Answer 19

Hay fever toxins mimic IgE and bind & stimulate release of Mast Cell granules

Question 20

What causes scurvy?

Answer 20

Lack of Vit C

Vit C is involved in recycling of enzyme proline hydroxylane which is needed to make collagen in rER

Question 21

Proteosome vs Lysozome

Answer 21

PROTEOSOME: recycling of intracellular cytoplasmic materials

LYSOSOME: digestion of endocytized material

Question 22

Orientation of Hepatocyte

Answer 22

BASAL: Sinusoids (Hepatic Artery branch & Portal Vein branch)

APICAL: Secrete bile into Bile Canaliculi which flows into Bile Duct

Question 23

Cytoskeleton Sizes

Answer 23

Microfil: 5-9nm
Int. Fil: 10-12nm
Microtub: 25nm

Question 24

Name for Intermediate Filaments in epithelia

Answer 24

Keratins

Question 25

Name for Intermediate Filaments in Muscle

Answer 25

Desmin

Question 26

Name for Intermediate Filaments in CT

Answer 26

Vimentin

Question 27

Name for Intermediate Filaments in neurons

Answer 27

Neurofilaments

Question 28

What are the roles of Microtubules?

Answer 28

(1) moving cargo around cell (2) cilia (bronchials, sperm) (3) spindle formation

Question 29

Cell-Cell Attachments

Answer 29

(1) ZONULA ADHERINS (cadherins, catenin, actin) (2) ZONULA OCCLUDENS (tight junctions) (3) DESMOSOMES (macula densa) (4) GAP JUNCTIONS (via connexons)

Question 30

How to recognize Microtubules on EM?

Answer 30

They are HOLLOW

Question 31

What does "Zonula Adherens" mean?

Answer 31

Zonula = Belt | cadherins, catenin, actin

Question 32

Descibe the Core Junction Complex in cells

Answer 32

Receptors: cadherins Linkers: Catenins Cytoskeleton: Actin

Question 33

Why are Cadherins so important for development?

Answer 33

Each tissue has specific cadherins so that they stick to only those of similar kind

Question 34

What do Catenins do?

Answer 34

(1) LINK cadherins to actin cytoskeleton | (2) signal transduction

Question 35

Where are desmosomes located?

Answer 35

usually more basal than Zolulas but can be located anywhere along lateral surface

Question 36

How are desmomes linked?

Answer 36

linked to stable intermediate filaments | **provide tensile strength

Question 37

Structure of Gap Junctions

Answer 37

Connexins = pores

Question 38

Cell-ECM Attachments

Answer 38

HEMIDESMOSOMES (stable) FOCAL ADHESIONS (dynamic)

Question 39

What do Hemidesmosomes anchor to?

Answer 39

Basal Lamina

Question 40

What do Focal Adhesions do? | Example?

Answer 40

* migrate according to kinase activity | * Movement of neurons to extend their dendrites to form new synapses

Question 41

What is the role of APC?

Answer 41

APC (tumor supp.) roams the cell and sends loose B-catenin to the Proteosome. (Wnt turns of APC)

Question 42

What gives microvili their shape?

Answer 42

Actin

Question 43

Invagination vs Evagination

Answer 43

Invagination: infolding of one part within another part of a structure Evagination: obtrusion of a layer or part to form a pouch.

Question 44

Why can't a protein that is normally synthesized on the rough ER be translated in the cytosol and THEN enter the ER lumen?

Answer 44

Proteins must cross into the ER as they are being synthesized

Question 45

Hyperplasia vs Hypertrophy

Answer 45

``` Hyperplasia = increase in number of cells Hypertrophy = increase in size of cells ```

Question 46

Hemidesmosomes VS Focal Adhesions

Answer 46

Hemidesmosomes = static Focal Adh = dynamic

Question 47

What can cause tissue enlargement?

Answer 47

(1) Hyperplasia (2) Hypertrophy (3) Increase in ECM (4) Increased Perfusion (5) Inflammation (6) Inc spaces between cells (7) Scarring/fibrosis

Question 48

Why does repeated elastase activity reduce the total amount of lung elastin over time?

Answer 48

elastin synthesis essentially ceases after the age of about 18 years

Question 49

Variants of a1 anti-trypsin

Answer 49

MM - normal pop MZ - hetero (Lucy's parents) ZZ - Lucy

Question 50

Where does Protein synthesis of lysosomal enzymes occur?

Answer 50

rER

Question 51

What is the function of Clathrin-coated vesicles?

Answer 51

Transport from trans face of the Golgi apparatus to lysosomes and from the PM into the cell.

Question 52

How and where are Lysosomal enzymes produced?

Answer 52

Lysosomal enzymes are synthesized in rough ER and are targeted through the Golgi before ending up in lysosomes.

Question 53

True or False: Alpha-1-antitrypsin is a neutrophil enzyme that degrades elastin in the lungs

Answer 53

FALSE ... here's the truth: Alpha-1-antitrypsin: proteinase inhibitor Elastase: neutrophil enzyme