Medicinal Botany Exam 2

What is the universal energy currency of life?

What is the universal energy currency of life?

Adenosine Triphosphate

Cellular respiration

glycolysis, citric acid cycle, oxidative phosphorylation

Net products of glycolysis are?

2 pyruvate, 2 ATP, 2 NADH

oxidation of sugars begins with..

glycolysis

Kinase

addition of a phosphate group to molecules

transfers a phosphate group from ATP to a substrate

Isomerase

catalyzes rearrangement of bonds within a single molecule

prepare molecules for chemical alterations to come

Dehydrogenase

catalyzes the oxidation of a molecule by removing a hydrogen atom plus an electron

enzyme glyceraldehyde 3-phosphate dehydrogenase generates NADH

Mutase

catalyzes shifting of a chemical group from one position to another

movement of phosphate by phosphoglycerate mutase

helps prepare substrate to transfer this group to ADP to make ATP

Glycolysis step one?

glucose is phosphorylated by ATP to form sugar phosphate

glucose plus ATP → glucose 6 phosphate plus ADP and H+

Glycolysis step two?

reversible rearrangement of the chemical structure (isomerization) moves the carbonyl oxygen from carbon 1 to carbon 2 forming a ketose from an aldose sugar

glucose 6 phosphate → fructose 6 phosphate

Glycolysis step three?

new hydroxyl group on carbon 1 is phosphorylated by ATP, in preparation for the formation of two three-carbon sugar phosphates, entry of sugars into glycolysis is controlled at this step, through regulation of the enzyme phosphofructokinase

Fructose 6-phosphate plus ATP → Fructose 1,6-Biphosphate plus ADP and H+

Glycolysis steps 1-3 is dedicated to?

energy investment

Glycolysis step 4?

6 carbon sugar is cleaved to produce two three carbon molecules, only the glyceraldehyde 3-phosphate can proceed immediately through glycolysis

fructose 1,6-Biphosphate → dihydroxyacetone phosphate + Glyceraldehyde 3-phosphate

Glycolysis step 5?

Dihydroxyacetone phosphate is isomerized to form glyceraldehyde 3 phosphate

Dihydroxyacetone phosphate → Glyceraldehyde 3-phosphate

Glycolysis steps 4-5 is dedicated to?

splitting and rearranging

glycolysis step 6?

two molecules of glyceraldehyde 3-phosphate are oxidized, the energy generation phase of glycolysis begins, NADH and a new high energy anhydride linkage to phosphate are formed

glyceraldehyde 3 phosphate + NAD+ and Pi → 1,3-biphosphglycerate + NADH and H+

Glycolysis step 7?

transfer to ADP of high energy phosphate group that was generated in step 6 forms ATP

1,3-biphosphglycerate + ADP → 3-phosphoglycerate + ATP

glycolysis step 8?

remaining phosphate ester linkage in 3-phosphoglycerate which has a relatively low free energy of hydrolysis, is moved from carbon 3 to carbon 2 to form 2-phosphoglycerate

3-phosphoglycerate → 2-phosphoglycerate

glycolysis step 9?

removal of water from 2-phosphoglycerate creates a high energy enol phosphate linkage

2-phosphoglycerate → phosphoenolpyruvate + H2O

glycolysis step 10?

transfer to ADP of the high energy phosphate group that was generated in step 9 forms ATP

phosphoenolpyruvate + ADP and H+ → pyruvate + ATP

what is glycolysis step 6-10 dedicated to?

energy generation steps

where does pyruvate go after glycolysis?

mitochondria

Fermentation

biochemical reaction that extracts energy from carbohydrates without using oxygen

products include ethanol, hydrogen gas, and lactic acid

End product of electron transport chain?

water and ATP

photosynthesis

light driven process in which CO2 is fixed to yield carbohydrates

Is CO2 reduced or oxidized during photosynthesis?

reduced

Is water reduced or oxidized during photosynthesis?

oxidized

Elucidation of photosynthesis?

notion that plants obtain nourishment from such insubstantial things as light and air took nearly two centuries to develop

violet has the shortest or the longest wavelength?

shortest

red has the shortest or the longest wavelength?

longest

light has properties of what?

waves and particles

pigment

substance that absorbs light

chorophyll

absorbs light in violet and blue wavelengths also red

reflects green

when chlorophyl absorb light, electrons are temporarily boosted to a..

higher energy level: excited state

what are the three possible fates of electrons as they return to a lower energy level?

energy is converted to heat or released as a photo (fluorescence), energy is transferred from the excited chlorophyll to a neighboring chlorophyll (resonance energy transfer), high energy electron is transferred to neighboring molecules (electron acceptor)

Chlorophyll a

occurs in all photosynthesis eukaryotes and cyanobacteria

chlorophyll b

occurs in plants and algae, has different absorption spectrum

an accessory pigment

accessory pigment

not directly involved in photosynthesis but helps, passes energy to chlorophyll a

carotenoids and phycobilins

an accessory pigment, passes energy to chlorophyll a

2 sets of reactions of photosynthesis

light and carbon fixation (Calvin cycle) reaction

light reactions

ATP is produced from AADP and inorganic phosphate using transfer of electrons and production of NADPH

Calvin fixation reactions

energy of ATP is used to link carbon dioxide covalently to an organic molecule and the reducing power of NADPH is used to reduce to a simple sugar

how many photosystems are involved in light reactions?

2

photosystems

two closely linked components: antennae and reaction complex

antennae complex

gather light energy and funnel it to the reaction center

reaction complex

contains a special pair of chlorophyll a molecules that are capable of actually using the energy

photosystem + LHC

photosystem complex

light harvesting complex (LHC)

usually associated with a photosystem to allow for even greater light gathering power

can photosystem 1 work independently of photosystem 2?

yes

cyclic electron flow

instead of electrons being passed to NADP+, they are shunted to an accepter in the ETC between PS1 and PS2

cyclic phosphorylation

process of photophosphorylation in which an electron expelled by the excited photo-center is returned to it after passing through a series of electron carriers

noncyclic phosphorylation

two-stage process involving two different chlorophyll photosystems in the thylakoid membrane

Calvin cycle starts with?

ribulose 1,5-biphosphate (RuBP)

first step of calvin cycle is catalyzed by?

rubisco

second step of calvin cycle

reduction of 3 phosphoglycerate to glyceraldehyde 3 phosphate

third step of calvin cycle

regeneration of RuBP

plants are what kind of growers?

indeterminate

what are the name of plant hormones

phytohormones

phytohormones

used for cellular communication in plants

what are the 3 basic elements for a plant hormone?

transport, induced chemical response, synthesis in one part for the plant

(True/False): phytohormones are synthesized in one location in the plant

false

5 classes of phytohormones?

auxins, cytokinins, ethylene, abscisic acid, gibberellins

Auxin

involved in plant length (growing longways)

ethylene

fruit ripening

Cytokinins

promotes cell division

abscisic acid

stomatal closure, induction of photosynthate transport from leaves to developing seeds

gibberellins

hyper elongation of shoots by stimulating both cell division and cell elongation producing tall plants

tropism

growth response involving bending or curving of plant from an external stimulus that determines the direction of the movement of the plant

positive tropism

toward the stimulus

negative stimulus

away from stimulus

types of tropism?

phototropism, gravitropism, hydrotropism, thigmotropism

statolith

amyloplasts that perceive gravity for the plants

gravity is through to potentially negatively affect what?

hydrotopism

change in turgor pressure that results in…

change in the structure of the leave/plant after a touch

MAMPs

microbe associated molecular patterns

plants recognize MAMPs and can…

elicit specific responses to help migrate incoming attacks (R proteins)

Plants also must be able to recognize what?

VOCs emitted by neighbors

VOCs

volatile organic compounds

salicylic acid is a key regulator in?

plant defenses against biotrophic threats

thermogenesis of some species

salicylic acid function

activation of disease resistance following pathogen invasion

Antagonistic pathway to jasmonic acid signaling…

one suppresses the other

Jasmonic acid

derivative of linolenic acid

Jasmonic acid is a key regulator in?

plant defenses against chewing herbivores and against certain species of microbes

evidence suggests jasmonic acid may also be a key regulator in…

defenses to drought, UV radiation, and other abiotic stresses

what type of compound is salicylic acid?

phenolic

Systemin

short polypeptide, mediates response to wounding by insects

connected with jasmonic acid

systemin defense includes..

upregulation of protease inhibitors that directly impedes the digestion of insects

cut grass smell is a..

plant defense (green leaf volatiles)

Green leaf volatiles

alerts nearby plants that damage has occurred which allows for priming of their immune system to attack threats

alerting fruit ripeness

Predators and parasites of herbivores use…

green leaf volatiles emitted by damaged plants to locate and consume herbivores

Regulation of VOCs

degrade rapidly, short dispersion, reduced risk of eavesdropping

diffusible molecules mediate reciprocal recognition between..

beneficial fungi and plant roots

Plants, like legumes, can actively recruit..

bacteria that can fix atmospheric nitrogren

True/False: nitrogen is a limited resource

True

Plant signals are used to attract pollinators by..

large visual and olfactory displays

When plants receive signals indicating both nutrient stress and herbivore attack they..

prioritize acquiring nutrients

True/False: plants have memory of past event such that speed, sensitivity, and effectiveness of response is enhance

true

What is enhance by plant memory?

speed, sensitivity, and effectiveness of response

Aristotelian view

plants lack movement and sensation (old view on plants)

Gleasonian view

Plants are independent members of loosely structured communities (time to reexamine this view)