Biochemistry - Cellular

Front 1

What regulates cell cycle phases? (3)

Back 1

a) cyclins
b) CDKs
c) tumor suppressors

Front 2

which is the shortest phase of the cell cycle?

Back 2

Mitosis

Front 3

List the phases of the cell cycle

Back 3

Prophase, Metaphase, Anaphase, Telophase

Front 4

Which phases of the cell cycle are of variable duration?

Back 4

G0 and G1

Front 5

What are CDKs?

2 descriptive words

Back 5

cyclin-dependent kinases

constitutive and inactive

Front 6

what are cyclins?
specific to?
activate?

Back 6

regulatory proteins that control cell cycle events;

phase specific
activate CDKs

Front 7

what must both be activated and inactivated for cell cycle to progress?

Back 7

Cyclin-CDK complexes

Front 8

What are tumor suppressors and what do they inhibit? a mutation results in?

Back 8

Rb and P53
Rb suppress G1-S
P53 suppress G1-S, S-M

mutation --> unrestrained growth
-retinoblastoma
-osteoscarcoma

Front 9

where do permanent cells regenerate from? list 4 examples

Back 9

from stem cells
1. neurons
2. skeletal muscle
3. cardiac muscle.
4. RBCs

Front 10

give examples of 2 stable/quiescent cells (and define)

Back 10

cells that can enter G1 from G0 when stimulated.
1. Hepatocytes
2. Lymphocytes

Front 11

define labile cells and give 4 examples

Back 11

labile cells never go to G0.
1) bone marrow
2) gut epithelium
3) skin
4) hair follicles

Front 12

RER
a) site of synthesis of?
b) what is RER in neurons called?
c) what do nissl bodies do?
d) give an example of an enzyme that is made by nissl bodies. what is the function of this enzyme?

Back 12

secretory (exported) proteins and of N-linked oligosaccharide addition to many proteins

b) Nissl Bodies
c) synthesize enzymes and peptide neurotransmitters
d) ChAT (choline acetyltransferase) --> makes Ach

Front 13

where are cytosolic and organellar proteins made?

Back 13

free ribosomes

Front 14

give two examples of cells that would be rich in RER

Back 14

mucous secreting goblet cells (of small intestine)

anti-body secreting plasma cells

Front 15

smooth endoplasmic reticulum (SER) is the site of?

which types of cells are rich in SER? (2 examples)

Back 15

steroid synthesis and detoxification of drugs and poisons

b) liver hepatocytes and steroid hormone producing cells of the adrenal cortex

Front 16

Golgi apparatus
a) function
b) golgi modifies? on?
c) golgi adds? on?
d) 2 additional functions?

Back 16

distribution center for proteins and lipids from ER to plasma membrane and vesicles

b) N-oligosaccharides on asparagine

c) O-oligosaccharides on Serine and Threonine
and
Adds mannose-6-phosphate to proteins for trafficking to lysosomes

d) glycosylations proteins and sulfation (of sugar and tyrosine)

Front 17

which amino acids can be modified by the golgi?

Back 17

serine, threonine, asparagine, tryosine

Front 18

I-Cell Disease
a) stands for?
b) acquired or inherited?
c) what type of disorder?
d) caused by?
e) clinical features?
f) actual enzyme missing that causes the failure of addition of the mannose-6-phosphate?

Back 18

a) inclusion cell disease

b) inherited

c) lysosomal storage disorder

d) failure of addition of mannose-6-phosphate to lysosome proteins (enzymes are secreted outside of cell instead of being targeted to lysosome)

e)
1) coarse facial features
2) clouded corneas
3) restricted joint movement
4) high plasma levels of lysosomal enzymes
5) often fatal in childhood

f) N-acetylglucosaminyl-1-phosphotransferase

Front 19

COPI
-what is it, what does it stand for, what is its function

Back 19

vesicular trafficking protein
-coat protein I
-retrograde (golgi--> ER)

Front 20

COP II
-what is it, what does it stand for, what is its function

Back 20

vesicular trafficking protein
-coat protein II
-anterograde (ER-->cis-golgi)

Front 21

Clathrin
a) helps with what?
b) explain function of adaptin, clathrin, dynamin,

Back 21

a) vesicular trafficking from trans-golgi --> lysosomes

plasma membrane -> endosome
(receptor mediated endocytosis)

b) cargo attaches to receptor, receptor attaches to "adaptin", clathrin attaches to adaptin and to other clathrin's attached to other adaptins . a bunch lined up attached to each other now
-dynamin pinches this bunch (vesicle)
-adaptin and clathrin recyles.
-naked vesicle (endosome) fuses with lysosome and cargo gets hydrolyzed so cell can actually use it.

Front 22

what is the function of a peroxisome?

Back 22

membrane enclosed organelle involved in catabolism of very long fatty acids and amino acids . also, generation of plasmalogens (imp for neural tissue)

Front 23

what are three mechanisms for proteolysis?

Back 23

a) degradation within lysosome
b) Calcium dependent enzyme
c) ubiquitin mediated proteosomal degradation

Front 24

what is the shape and function of a proteosome?

Back 24

a barrel-shaped protein complex that degrades damaged or unnecessary proteins tagged for destruction with ubiquitin

Front 25

Microtuble
a) what is the shape of a microtubule?
b) what is a microtubule composed of?
c) what is bound to each dimer?
d) what are three structures that microtubules are incorporated into?
e) compare the speed of microtuble growth vs collapse
f) microtubules are involved in what kind of transport?
g)what do molecular motor proteins do?
h) dynein does what? what dir, +/- signs
i) kinesin does what?

Back 25

a) cylindrical
b) helical array of polymerized dimers of alpha and beta tubulin
c) 2 GTP
d) flagella, cilia, mitotic spindle
e) grow slowly, collapse quickly
f) slow axoplasmic transport in neurons
g) transport cellular cargo toward opposite ends of microtubule track
h) retrograde to microtuble (+-->-)
i) anterograde to microtuble (- -->+)

Front 26

list 5 types of drugs that act on microtubules and what they are used to treat.

Back 26

1)mebendazole/thiabendazole(antihelminthic)
2) Griseofulvin (antifungal)
3) Vincristine/Vinblastine (anti-cancer)
4) Paclitaxel (anti-breast cancer)
5) Colchicine (anti-gout)

Front 27

Chediak-Higashi Syndrome
a) what is it?
b) results in?

Back 27

a) Microtuble polymerization defect resulting in decreased fusion of phagosomes and lysosomes (phagosomes need MT to get to places in the cell)

b) recurrent pyogenic infections,
partial albinism,
peripheral neuropathy

Front 28

a) describe Cilia Structure
b) on what subunit is the dynein ATPase attached to?
c) what allows cilia to move in a coordinate fashion?

Back 28

9+2 arrangement of microtubles.
9 dimers outside ring, 2 in center.
b) to the A subunit
c) gap junctions (communication)

Front 29

Kartagener's Syndrome
a) what is it?
b) results in?
c) associated with?
d) also called?

Back 29

a) immotile cilia due to dynein arm defect
b) male/female infertility (sperm immotile)
bronchiectasis, recurrent sinusitis (bacteria and particles not pushed out)
c) situs inversus
d) primary ciliary dyskinesia

Front 30

cytoskeletal elements

actin and myosin make/involved in (4)?

Back 30

microvilli, muscle contraction, cytokinesis, adherens junctions

Front 31

cytoskeletal elements

microtuble
a) function
b) form/examples/function (5)

Back 31

a) movement
b) cilia, flagella, mitotic spindle, axonal trafficking, centrioles

Front 32

cytoskeletal elements

intermediate filaments
a) function
b) examples

Back 32

a) vimentin, desmin, cytokeratin, lamins (ABC), glial fibrillary acid proteins (GFAP), neurofilaments (axons), peripherin (neurons)

Front 33

plasma membrane composition
a) describe
b) contains? how much?
c) what happens if high cholesterol or high long saturated FA content?

Back 33

a) asymmetric bilayer
b) cholesterol (50%), phospholipids (50%),
sphingolipids, glycolipids, proteins
c) increased melting temperature, decreased fluidity (no double bonds)

Front 34

Vimentin
a) cytoskeletal component?
b) cell type?
c) id?

Back 34

a) Intermediate filaments
b) connective tissue
c) sarcoma, some carcinoma

Front 35

desmin
a) cytoskeletal component?
b) cell type?
c) id?

Back 35

a) intermediate filament
b) muscle
c) rhabdomyosarcoma, leomyosarcoma

Front 36

cytokeratin
a) cytoskeletal component?
b) cell type?
c) id?

Back 36

a) intermediate filaments
b) epithelial cells
c) carcinoma, some sarcoma

Front 37

GFAP
a) cytoskeletal component?
b) cell type?
c) id?

Back 37

a) intermediate filament
b) neuroglia
c) astrocytoma

Front 38

Neurofilaments
a) cytoskeletal component
b) cell type?
c) id?

Back 38

a) intermediate filaments
b) neurons
c) adrenal neural blastoma (primitive neuroectodermal tumor)

Front 39

Sodium Pump
a) located where?
b) ATP site is on what side?
c) ratio?
d) explain whats going with ATP and the pump
e) name 2 drugs that inhibit sodium pump

Back 39

a) Na+-K+ ATPase in the plasma membrane
b) ATP site on the cytoplasmic side
c) 3 Na+ leave the cell, 2 K+ enter the cell
d) ATP attaches, gives phosphate (pump is phosphorylated), 3 Na leave. then, phosphate given off, 2 K+ enter.
e) Ouabain, Cardiac Glycosides

Front 40

what does Ouabain do?

Back 40

Ouabain inhibits the sodium potassium pump by binding to the K+ site

Front 41

how do cardiac glycosides work? give two examples.

Back 41

Digoxin, Digitoxin.

directly inhibit Na/K ATPase (sodium out, K in), which leads to indirect inhibition of Na/Ca (sodium in, calcium out) , therefore increase in intracellular calcium.

increased calcium = increased cardiac contractility.

Front 42

what is the most abundant protein in the body?

Back 42

collagen

Front 43

a) what is the function of collagen generally?
b) type 1
c) type 2
d) type 3
e) type 4

Back 43

a) organize and strengthen extracellular matrix
b)1: strong: bone, skin, tendon, dentin
c) 2: slippery: carTWOlage (hyaline), vitreous body, nucleus pulposis
d) 3: bloody: reticulin, skin, blood vessels, uterus, fetal tissue, granulation tissue
e) 4: basement membrane or basal lamina (of kidneys, ears, eyes)

Front 44

collagen synthesis: step 1

Back 44

1) synthesis (RER): translation of collagen alpha chains (pre-pro-collagen) . usually glycine-x-y (proline, lysine)

Front 45

collagen synthesis: step 2

Back 45

in ER. hydroxylation of specific proline and lysine residues (requires vitamin C)

Front 46

collagen synthesis: step 3

Back 46

in ER. glycosylation of pro-alpha-chain hydroxylysine residues and formation of procollagen via hydrogen and disulfide bonds (triple helix of 3 collagen alpha chains)

Front 47

collagen synthesis: step 4

Back 47

exocytosis of procollagen into extracellular space

Front 48

collagen synthesis step 5

Back 48

proteolytic processing. cleavage of terminal regions of procollagen transforms it into insoluble tropocollagen

Front 49

collagen synthesis step 6

Back 49

cross-linking. reinforcement of many staggered tropocollagen molecules by covalent lysine-hydroxylysine cross-linkage (by lysyl oxidase) to make collagen fibrils.

Front 50

collagen synthesis: step 1-6 titles

Back 50

1: synthesis (RER) : pre-procollagen alpha
(glysine-proline-lysine)
2: hydroxylation: proline lysine residues
3: glycosylation: of pro-alpha-chain hydroxylisine + procollagen by hydrogen bonds/sulfides (triple helix of 3 alpha chains)
4: exocytosis
5: proteolytic processing. cleavage (proteolysis) of terminal regions of procollagen -->tropocollagen (insoluble)
6: cross-linking: reinforcement of staggered tropocollagen molecules by covalent lysine-hydroxylysine cross-linkage (by lysyl oxidase) to make collagen fibrils

Front 51

osteogenesis imperfecta
a) also called?
b) how do you get it?
c) mc form inheritance? type? collagen?
d) 4 clinical features
e) why the blue sclera?
f) what can this disease be confused with?
g) type II incidence? clinical features?

Back 51

a) brittle bone disease
b) inherited
c) AD, type 1, type 1 collagen
d) multiple #s, blue sclerae, hearing, dental
e) translucency of CT over choroid
f) child abuse
g) 1:10,000, fatal in utero or neonatal period

Front 52

Ehlers-Danlos Syndrome
a) what is it?
b) 3 clinical features?
c) how many types?
d) 3 associations?
e) which type of collagen most frequently affected?

Back 52

a) faulty collagen synthesis
b) 1) hyperextensible skin, 2) hypermobile joints, 3) tendency to bleed (easy bruising)
c) 6 types
d) berry aneurysms, organ rupture, joint dislocation
e) type III

Front 53

Alport Syndrome
a) cause?
b) whats abnormal?
c) inheritance of mc form?
d) characterized by?

Back 53

a) variety of gene defects
b) type IV collagen
c) X-linked recessive
d) progressive hereditary nephritis & deafness. maybe ocular disturbance. (lenticonus: thinning around capsule of lens)

Front 54

elastin
a) where is elastin found?(5)
b) what is the function of ligamenta flava
c) elastin is rich in what amino acids? what forms of these?
d) how is elastin held together?
e) what breaks down elastin?
f) what inhibits elastase?

Back 54

1) lungs 2) large arteries 3) elastic ligaments 4) vocal cords 5) ligamenta flava

b) ligamenta flava connect vertebrae --> relaxed and stretched conformations

c) proline, glycine (non-hydroxylated forms)

d) tropoelastin with fibrillin scaffolding
e) elastase
f) alpha 1 antitrypsin

Front 55

Marfan's Syndrome
a) what is it
b) clinical features

Back 55

caused by a defect in fibrillin

b) hyperelastic joints, problem with heart valves, aorta (dissection), tall long limbs, arachnodactyly

Front 56

Emphysema
a) cause

Back 56

a) alpha 1 antitrypsin deficiency (excess elastase activity)

Front 57

why do we get wrinkles?

Back 57

reduced collagen and elastin production

Front 58

c

Back 58

c