Exam 3

Question 1

Outer membrane

Answer 1

Continuous with ER, shared lumen and communication between nucleus and cytoplasm

Question 2

Envelope

Answer 2

2 lipid bilayers, protect nucleus and regulate material exchange

Question 3

Mutation in lamin genes

Answer 3

Progeria - accelerated aging + health issues

Question 4

Lamin critical role

Answer 4

Anchor chromosomes in interphase - influencing gene expression

Question 5

Euk DNA contains

Answer 5

Exons, introns, reg sequences

Question 6

Chromosome painting

Answer 6

Attaching single-stranded DNA with florescent dyes to chromosomes to distinguish in karyotype. Sheds light into arrangement and # of chromosome

Question 7

Nucleolus

Answer 7

Cluster of ribosomal RNA genes, proteins, and chromo: 13, 14, 15, 21, 22

Question 8

Cohesins

Answer 8

Organize interphase chromatin

Question 9

Condensins

Answer 9

Compact interphase chromatin into mitotic chromo before cell division (replace cohesins)

Question 10

Why so tight?

Answer 10

H1 and specialized chromo proteins

Question 11

Histone tails can be:

Answer 11

Methylated, acetylated, phosphorylated to promote expansion or condensation of chromatin

Question 12

Mod made by ___________, removed by ___________, acted on upon _________

Answer 12

Writers, erasers, readers

Question 13

Heterochromatin

Answer 13

Highly condensed, silent genes.

Question 14

Facultative

Answer 14

Temp condensed

Question 15

Constitutive

Answer 15

Permanently condensed. Example: telomere and centromere

Question 16

Euchromatin

Answer 16

Less condensed chromatin associated with genes that are expressed

Question 17

Epigenetic inheritance

Answer 17

Heterochromatin can be inherited

Question 18

Rapid signal

Answer 18

Alter activities of proteins within the cell

Question 19

Slow signal

Answer 19

Changes in gene exp pathways. Time needed for synthesis of new mRNAs and proteins

Question 20

TRAIFD

Answer 20

Transduce, relay, amplify, integrate, feedback, distribute

Question 21

Agonist

Answer 21

Activates GPCR

Question 22

Antagonist

Answer 22

Keeps GPCR in off state

Question 23

GAP’S

Answer 23

Lowers activation E for Galpha to hydrolyze the GTP

Question 24

Signaling targets downstream?

Answer 24

Membrane-bound enzymes to make 2nd messengers. Examples: cAMP, IP3, DAG

Question 25

Camp

Answer 25

Generated from ATP. Degraded by phosphodiesterase. Mediates PKA for fast AND slow. Example: glycogen utilization by skeletal muscles (short), increased cAMP activates gene transcription through PKA (long)

Question 26

ER calcium

Answer 26

Internal reservoir for signaling pathways

Question 27

3 main classes of cell surface receptors

Answer 27

Ion channel, G-protein, enzyme

Question 28

exp of PKC

Answer 28

neuron development, cell polarity, and if over exp then cancer

Question 29

Activated Akt

Answer 29

Promote cell survival and/or stimulate cell

Question 30

Intermediate filaments

Answer 30

Strongest, withstands mechanical stress

Question 31

How to use IF for cancer

Answer 31

Where cancer originated from and if metastatic

Question 32

Intermediate filaments in epithelial cells

Answer 32

Keratins

Question 33

Keratins cell to cell interaction with membrane

Answer 33

Desmosomes

Question 34

How do Intermediate Filaments differ from Microtubules and Actin?

Answer 34

- No polarity - No nucleotide - Dynamics are primarily regulated by extrinsic factors (kinases and phosphatases) - No Motor proteins

Question 35

Microtubules

Answer 35

Network of cytoplasmic filaments. Hollow cylinders of alpha (-) and beta (+) tubulin. Transform into heterodimers. Form wall in head to tell manner - protofilaments.

Question 36

Dynamic instability

Answer 36

Ability to grow and shrink while total mass remains constant

Question 37

Catastrophe

Answer 37

Growth to shrinking

Question 38

Rescue

Answer 38

Shrinking to growth

Question 39

EB1

Answer 39

Localizes to plus end

Question 40

Centrosomes

Answer 40

Microtubules grow off of with gamma tublin. Minus end capped by interaction with gamma

Question 41

Augmin

Answer 41

Recruit gamma ring complex to attach microtublin at low angle - maintains general polarity of network

Question 42

Kinesins

Answer 42

Binds microtubules, ATP, and tail domain to cargo. Walk along microtubules towards +. 8 steps. Dyneins walk in -, 8, 16,32. Hydrolyze ATP to power conformational changes.

Question 43

Same directions?

Answer 43

One inactivated or dominates the net force

Question 44

Flagella

Answer 44

Long a present in 1 or 2 copies per cell

Question 45

Cilia

Answer 45

Shorter 10-100 copies per cell

Question 46

Axoneme

Answer 46

Core within cilia and flagella, 9+2. Force on one doublet is excerpted on the neighbor

Question 47

New actin filaments within lamellipodia

Answer 47

daughter F-actin filaments that grew at a ~70 degree angle from a mother filament by the Arp2/3 complex.

Question 48

Actin func

Answer 48

assembled into a scaffolding that gives cells their shape, used to generate forces during cellular movements (pushing and pulling)

Question 49

Filamin cross-links

Answer 49

actin filaments into a meshwork and has mechanical strength

Question 50

lamellipodium

Answer 50

branched networks of short filaments