Chapter 7,8,9 (exam 2)

two common effector proteins are

adenyly cyclase and phospholipase

calmodulin, a cytoplasmic protein, bind kinases, ion channels

causing cellular responses

an inactive steroid receptor has an inhibitor in the DNA domain

steroid binding displaces inhibitor

RTK's have an extracellular binding domain

and an intracellular kinase domain

Photosynthesis uses the product of respiration (namedly CO2)

as starting substrate

enzymatic membrane receptors are enzymes activated by ligand…

almost all are protein kinases

effector proteins activated by G proteins

produce a second messenger

CAM plants close stomata during the day and remove

CO2 from malate to use it in the calvin cycle

In synaptic signaling nerves release a signal (neurotransmitter)

that bind to receptors on nearby cells

GPCR is the largest type of receptors

that act by coupling to a G protein

thylakoid membranes are surrounded by a

semiliquid called stroma

If an organism lives on organic compounds produced by others its a

hetertroph

same signaling molecule

can produce different effects

Chrolophylls (a and b) and cartoenoids are the two general pigments

present in green plants

respiration uses the product of photosynthesis (namely glucose)

as starting substrate

receptors can be cell surface on the outside of

cell membrane or intracellular

All G proteins are active when bound to GTP

and inactive when bound to GDP

the proton gradient created is used to produce ATP by

chemiosmosis in ATP synthase

photosynthesis in c4 plants occur in mesophyll cells first

and then in bundle sheath cells

All organisms use cellular respiration to extract energy from

organic molecules

accessory pigments (chlorphyll b cartenoids, etc)

absord light on different regions

If an organism extracts energy through photosynthesis

it is a autotroph

ATP is produced by

substrate-level phosphorylation (SLP), oxidative phosphorylation (OxP)

protons travel through a channel in Fo which causes rotation

of FO that activates Fl to produce ATP

four basic ways of communication

direct contact, paracrine, endocrine, and synaptic signaling

glucose and frutose makes sucrose as the vehicle

to transport glucose for starch and cellulose syntheses

In endocrine signaling, hormones released travel to affect

cells throughout the body

pigments in antema gather photons and feed the reaction centers

process is complementary

scaffold proteins organize kinase cascade components into a

protein complex for optimal function

pigments are present in antema complexes surrounding a

mostly chlorophyll (a) reaction center

energy yield of respiration per unit of glucose

32 ATP in bacteria, 30 ATP in eukaryotes

MAP kinases are cytoplasmic, stimulate cell division,

and are activated by a kinase cascade

binding of the hormone to receptor causes

the complex to shift to nucleus to regulate gene expression

b6f complex is a proton pump embedded in the thylakoid membrane

that passes electrons to PC

nonpolar, steroid hormones cross freely in the

membrane and bind intraceulluar receptors in cytoplasm

G protein provided link between receptor and effector proteins

usually enzymes G protein activates

photons excite the electrons in the poryphyrin ring

and the electrons are shuttled away

RTK's influence cell cycle, migration, metabolism, and proliferation

and can induce cancer if altered

only chlorphyll (a) in reaction centers absorb blue and red light…

and converts it to chemical energy

phosphlolipase C leaves P1P2 into IP3 and DAG

both are secondary messenger I= inositol

protein phosphorylation uses mostly ATP on Oh groups of

serine, theronine, or tyrosine residues

Scaffold proteins provide efficiency but reduce amplification

as each kinase affects one line

Oxaloacetate is converted to maltate which releases

CO2 for the calvin cycle in the bundle-sheath

CAM plants (succulents, cacti, pineapple) open stomata at night

take CO2 and make malate from PEP

carotenoids have chains of alternating double bounds

and also serve as antioxidants

kinase domain phosphorylates insulin response protein that promotes

glycogen synthesis

photosynthesis in C3 and CAM plants occur

in bundle-sheath cells

steroid receptor has hormone- binding domain

DNA binding domain, and coactivor domain

in direct contact molecules on the surface on one cell

are recognized by receptors on adjacent cells

carbon fixation reactions (calvin cycle)

take place in the stroma

A cell response to a signal may be adding (kinase) or removing

phosphates to an enzyme

RUBISCO does carboxyilation in normal conditions and

oxygenation of RuBP in hot conditions

grana are stacks of flattened sacs

of thylakoid membranes

light depedent reactions occur in the

thylakoid membrane of chloroplasts

ATP has 2- sub portions

-Fo, a membrane- bound complex, Fl, a stalk and knob with enzymatic activity

light dependent reactions sunlight

is used to make ATP and NADPH

carbon fixation reactions CO2, ATP, and NADPH

are used to make sugars

pigments absorb photons of energy

which are inversely propotional to wavelength

chlorophylls have Mg in the center of an unsaturated ring structured called

porphyrin ring

the visible spectrum covers

400nm (blue, high energy) to 740nm (red, low energy)

the enzyme used in calvin cycle is

RUBISCO (ribulose bisphosphate carboxylase/oxygenase)

photosynthesis

combine CO2+H2O+light to make carbohydrates

difference between chlorophylls is that (a) has a

side CH3 group and (b) has an aldehyde CHO

MAP (mitrogen-activated protein) kinases are a series of kinases

that phosphorylate each other

additional ATP in plants is produced by skipping PSI,

making it a cyclic photophosphorylation

cells use ATP, from cyclic and noncyclic photophosphorylation, and NADPH from

PSI to make sugars

oxygenic photosynthesis (using O2)

is carried out by cyanobacteria , 7 groups of algae, all land plants (in chloroplasts)

3 turns of Calvin cycle produce a new G3P and 2G3P

are used to make 1 glucose outside the cycle

sulfur bacteria has one cyclic photosystem

purple non-sulfur bacteria reaction center is P870

cell response, such as regulation,

to a lipid-soluble signal vary greatly due to coactivators

when insulin binds to an RTK, dimerization and autophosphorylation

occur in the kinase domain

C4 and CAM plants use C3 and C4 pathways but in

C4 plants both pathways occur in different cells

adenylyl cyclase produces cAMP that actives protein kinase A (PKA)

which phosphorylates proteins

9 isoforms of epinephrine cause different G proteins

leading to different signal transduction pathways

plants that use calvin cycle are called C3 plants

there are also C4 plants and CAM plants

CO2 and O2 compete for the active site of RuBp

which explains the name of the enzyme

in paracrine signaling signal molecule (hormone)

released by a cell affects neighboring cellls

IP3 binds to gated Ca ion channel receptors on ER

releasing Ca+2 that binds to calmodulin

cell surface receptors include

G- protein- coupled (GPCR), tyrosine kinase (RTK) guanlyl cyclase

the electron transport (ETC) is a series of membrane bound electron carriers

embedded in the inner mitochondrial membrane

requires a ligand (signal molecule) and a receptor protein to which the ligand binds

signal transduction

differnet receptors can produce same 2nd messengers.

glucagon and epinephrine cause glucose release

Intraceullar receptors can act as enzymes

No catalyzes the synthesis of cGMP through guanyly cyclase

RAS is active bound to GTP, inactive to GDP

activated RA's activates first kinase in MAP cascade

GPCRs and RTKs can activate the same pathways

both activate MAP kinase and phospholipase C

the lost electrons in PS11 are replaced by electrons

from the oxidation of H20 to 02

stages of photosynthesis

has two stages, light dependent reactions, carbon fixation reactions

photosystem II has 10 proteins+4Mn+electron transfer…

components + 2P680 chlorophyll (a) units

the calvin cycle is also called C3 photosynthesis

because the first intermediate has 3 carbons (G3P)

electrons in PQ go through the b6f complex that then

pumps protons into the thylakoid space

electrons from NADH and FADH2 move through the carriers of ETC and then react with

O2 to produce H20, 02, is the ultimate electron acceptor

2P680 chlorphyll (a) in PS11 absorb 2 photons

exciting 2 electrons that move to plastoquinone (PQ)

RAS protons are small G proteins, linking RTK with MAP kinase cascade,

mutate in many human tumors

cGMP (cyclic guanosine monophosphate)

is an intraceulluar messenger that relaxes smooth muscle

fats catabolism

fats are broken down to fatty acids are glycerol, fatty acids are converted to acetyl- CoA groups by B oxidation

after completion of the citric acid cycle, one glucose has been oxidized to

6CO2, 4ATP, 10NADH and 2 FADH2

corn and many grasses (C4 plants) add CO2

to make pyruvate to make oxaloacetate (C4 in mesophyll)

pyruvate oxidation by a complete pyruvate dehydrogenase enzyme produces acetyl- CoA and takes place

in the mitochondria of eukaryotes and in the plasma membrane of prokaryotes

photosystem 1 has 12-14 proteins+2P700 chlorophyll (a)

accepts PC electrons to make NADPH

the absorption spectrum gives range and efficiency

of molecues to absorb photons