Signaling
Describe the 5 types of signaling?
Endocrine: long distance (public broadcast)- travel via blood or sap
Neuronal: long distance (telephone)- more targeted release of signaling molecules
Paracrine: signal nearby cells (local)- signal molecules released to extracell. fluid
Autocrine: signal molecules bind to receptors on themselves (talking to yourself)- cell activates own signaling
Contact dependent: signal molecules on membrane (handshake)- requires physical contact
What is the name of the secondary Messager in epinephrine signaling?
What does it cause?
cAMP (cyclic AMP)
cAMP binds to protein kinase A and activates it
What is the starting molecule in glycolysis?
What are the net outputs of glycolysis per glucose?
glucose
2 pyruvate, 2 ATP, and 2 NADH
What are the two main stages of photosynthesis and where do they occur?
Light Rxns: Thylakoid Membrane
Light Independent Rxn (Calvin Cycle): Stroma
What is needed for the generation of NADPH and ATP in the first step of photosynthesis?
Sunlight absorption- there has to be an increase in energy
Positive vs. Negative Feedback?
+: products stimulate the production of more produces- massive change in a short period (all or nothing)
-: products repress production of products- finely tuned
What enzyme coupled receptor is the best? Describe some features
Tyrosine Kinase
They are transmembrane proteins with kinase domains in the cytoplasmic tail
In glycolysis, what are the products of splitting fructose?
What happens to the products?
GAP and DAP
DAP is isomerized by isomerase to GAP: after this you have 2 GAP
What is the final electron acceptor in the light reactions?
NADP+
Where do GAP molecules go after being synthesized in photosynthesis?
They can be exported into the cytosol in exchange for P ions and used to synthesize sucrose
Or stay in chloroplast to be converted to starch or fat
What is epinephrine? What is the main reason for epinephrine signaling?
It is a hormone secreted by the adrenal glands- fight or flight
Focus of glycogen breakdown= glucose
What does the binding of insulin to a receptor cause?
The kinase domains in the receptor will undergo trans-autophosphorylation- this causes intercellular proteins to bind
In the Citric Acid Cycle what is succinate dehydrogenase?
Enzyme that catalyzes the oxidation of succinate to fumarate
Reduces FAD to FADH2- FAD accepts 2 H+ atoms from succinate
What is the starting molecule in the Calvin Cycle?
What is the main goal?
CO2- which binds to rubisco to convert the CO2 to an organic molecule
GAP
What are the 2 main sections of ATP synthase and what are the subunits within them?
F0- a, b, c
F1- alpha, beta, gamma
What enzyme activates glycogen phosphorylase? How?
What does glycogen phosphorylase do?
Glycogen phos. is activated by phosphorylase kinase by using ATP to phosphorylate the enzyme (add phosphate group)
GP breaks down glycogen to glucose
What is the main goal of insulin? (What does it regulate and how?)
Regulates glucose uptake
1. Insulin binds to receptor
2. Signal pathway activates
3. Protein Kinase B moves cytoplasmic vesicles with glucose transporters (GLUT 4) fuse to PM
4. Glucose uptake increases
What is the order of the structure the electron goes through from NADH?
How many protons are pumped?
NADH -- Complex I (4 H+) -- Ubiquinone -- Complex III (4H+) -- Cytochrome C-- Complex IV (2H+)
10 protons total
In the Calvin Cycle what is PGA converted to and how is this done?
Uses ATP to convert PGA to BGA
How does the rotation of the enzyme cause the formation of ATP?
The beta subunit is forced into a loose, tight and open conformation
What subunit on the G-protein has GDP attached to it?
What eventually happens to the GDP and how does this affect the G-Protein?
Alpha Subunit
GDP will switch to GTP which causes the G-protein to dissociate from the GPCR and the alpha subunit binds to the effector.
What is signal transduction?
Transmission and flow of information in a cell- conversion of one signal to another
What is the starting molecule of TCA?
What are the net results of TCA?
Acetyl CoA
3 NADH, 1 GTP, 1 FADH2, and 2 CO2 as waste
What is the complete path of electron in the light rxn?
Sun excites P680 to P680+ which split water and strips it of its e-
E- travels to photosystem II --- Plastoquinone --- Cytochrome b6f Complex --- Plastocyanin --- Photosystem I --- Ferredoxin --- Ferredoxin NADP+ reductase --- NADPH
How did mitochondria and chloroplasts evolve?
Endosymbiosis Theory