Ppws 3506 Test 2

Front 1

What is the difference between primary and secondary metabolites?

Back 1

Primary have direct roles in plant growth and development (photosynthesis, respiration, etc.). Secondary have no direct role in growth and development (an exception might be lignin or hormones), but function in interactions between plants and their biotic environment.

Front 2

Provide some examples of how man uses secondary chemicals?

Back 2

Medicines, flavorings, fragrances, poisons, herbicides, etc.

Front 3

What are the general functions of secondary metabolites in plants?

Back 3

Hormones like GA, Brassinosteroids, ABA, cytokinins, signaling as in symbiotic relationships, parasitism, defense, etc., Pollinator attractants, defensive compounds, structural support as in lignin

Front 4

3 major groups of secondary compounds

Back 4

phenolics, terpenoids, nitrogen-containing compounds

Front 5

Structure and synthesis of terpenoids

Back 5

derived from Mevalonic Acid Pathway/Acetyl CoA and MEP/3C sugars forming the basic isoprene unit which is phosphorylated and becomes active DMAPP and IPP which condense head to tail forming units of 5C (C10, C15, C20, etc.).

Front 6

Structure and synthesis of nitrogen-containing compounds

Back 6

most varied, but contain N. Synthesized from a variety of amino acids. Examples are alkaloids, glucosinolates, nonprotein amino acids, etc.

Front 7

Structure and synthesis of phenolics

Back 7

derived from Shikimic Acid pathway via phenylalanine produced from erythrose-4-phosphate and PEP acid and /or malonic acid pathway via acetyl CoA (in case of flavonoids). Examples are lignins, tannins, simple phenolics, flavonoids.

Front 8

Provide some specific roles that terpenoids play in plants.

Back 8

Hormones, sterols, dolichols, phytol side chain of chlorophyll, defense, carotenoids for photosynthesis and UV light protection, etc.

Front 9

Provide some specific roles that phenolic compounds play in plants

Back 9

Flower colors (anthocyanins), UV light protection, structure, signaling, attractants, defense

Front 10

What are the four major groups of flavonoid compounds?

Back 10

Flavones, flavonols, anthocyanins, isoflavones

Front 11

Give at least one example of how secondary compounds produced in plants don’t hurt the plants themselves.

Back 11

Can be compartmentalized (vacuole), enzymes that activate compound could be stored separately, plants could extrude away from roots, might be inactive until released into environment – may be others

Front 12

What types of feeding strategies are utilized by herbivores? Identify examples of herbivores that use these strategies.

Back 12

Wood eaters (xylophages)- termite, sap feeders (mucivores)- butterfly, leaf eaters (folivores)- sloth, fruit eaters (frugivores)- mammals, seed eaters (granivores) mice, pollen and nectar feeders (palynivores and nectarivores)- hummingbird – know an example of each type

Front 13

Positive effects of herbivory on plant growth

Back 13

examples of positive include attracting pollinators such as bee orchid using mimicry, overcompensation in Scarlet gilia, acacia trees and ants

Front 14

Negative effects of herbivory on plant growth

Back 14

: reduced photosynthesis, alterations in sugars in storage tissues, reduction in transpiration, etc due to destruction of vascular tissues, loss of apical dominance, etc

Front 15

What are the six factors that determine the magnitude of herbivory effects on plants?

Back 15

Life stage of plant, type of tissue consumed, timing of herbivore attack, genome of plant, environmental conditions, species response

Front 16

Give at least one example of coevolution between insect herbivores and plants

Back 16

Could use monarch butterfly and milkweed an viceroy butterfly

Front 17

Give an example of a nonprotein amino acid, and how is it toxic to herbivores?

Back 17

Canavanine similar to amino acid arginine. Transfer RNA can’t recognize the difference to fake amino acid incorporated into proteins. Since not the same protein folds differently and is non functional. Eventually leads to death of organism.

Front 18

What is a bioassay? Give at least one example.

Back 18

Use of living process to show activity of a chemical. Ex: seed germination, seedling growth, root growth, etc

Front 19

What must you do in order to prove that an allelopathic chemical is involved in a sick plant and not competition?

Back 19

Isolate pure chemical. Identify chemical. Apply chemical back to plant and see same effect.

Front 20

Nicotine

Back 20

alkaloid, formed in root of tobacco, insect deterrent, also drug of choice for smokers

Front 21

PAL and HMGR

Back 21

both are major enzymes in either Shikimate or Mevalonate Pathway. Both are inducible following pathogen, herbivore attack. Phenylalanine Ammonia Lyase converts phenylalanine to cinnamic acid (first product in phenolic synthesis) and 3-hydroxymethyl glutaryl Coenzyme A reductase converts HMG CoA into mevalonic acid (first product in terpenoid biosynthesis)

Front 22

Classification of terpenoids (mono-, di-, tri, sesqui-, tetra-)

Back 22

C10- simple volatiles, flavors, scents
C20- form the basis for biologically important compounds such as retinol, retinal, and phytol. Known to be antimicrobial and antiinflammatory
C30- shark liver oil
C15- phytoalexins like capsaicin or capsidiol
C40- lycopene, alpha-, beta-, and gamma-carotenes

Front 23

Pyrethrum

Back 23

type of terpenoid produced in chrysanthemum family that deters insects. Many insecticides are based on these compounds

Front 24

Phytoecdysones

Back 24

plant produced insect like hormones which interfere with a herbivores life cycle

Front 25

Glycosides and some examples

Back 25

Compounds which contain a bound sugar. Could be one of those types of mixed compounds with nitrogen containing and/or phenolic containing parts. Becomes active when sugar released and if cyanogenic glycoside will break down to produce hydrogen cyanide gas. Ex: amygdalin, but there are many others

Front 26

Saponins

Back 26

Steroidal and glycosidal molecules with soaplike properties – if injected, disrupts red blood cells and other cellular membranes. If ingested interferes with sterol uptake. Ex: cardiac glycosides like digitoxin from foxglove

Front 27

Condensed vs hydrolysable tannins

Back 27

two classes of phenolic compounds which are anti-nutritive. Bitter taste so deter herbivores, precipitate proteins in the gut, so hard to digest and prevents uptake of nutrients. Used in the leather industry for tanning hides

Front 28

Glucosinolates

Back 28

nitrogen containing compounds with a sugar attached. When broken down produce cyanate and sulfate containing products which are volatile and toxic to herbivores. Mainly in Brassica species. May have antithyroid and goitrogenic effects

Front 29

Alkaloids and some examples

Back 29

nitrogen containing molecules, toxic to herbivores, esp. mammals, neutrotoxic and also may affect heart muscle, cell division so many useful in medicines, as poisons, stimulants, etc. – nicotine, caffeine, morphine, codeine, anti-cancer – vinblastine/vincristine, poisons - strychnine, batrachotoxins, mitosis inhibitors - colchicine

Front 30

Canavanine

Back 30

nonprotein amino acid, looks like arginine, mistakenly placed in proteins and makes them defective

Front 31

Cover and smother crops

Back 31

Cover – crops grown between periods of regular cropping to prevent soil erosion, suppress weeds, maintain nutrients and water
Smother – similar to above, but grow so thickly and quickly that they overshadow other plants – used for same purposes
Examples: rye contains DIBOA and other phenolics, oat (scopoletin and phenolics), Brassicas (glucosinolates), alfalfa (medicarpins), sorghum (dhurrin, sorgoleone)

Front 32

Green manure crops – know some examples and the compounds produced

Back 32

Crops turned over or incorporated into soil while green or soon thereafter. Many examples same as cover/smother crops but also include legumes like clovers that release phenolics to suppress weed growth

Front 33

Cinmethylin

Back 33

Natural herbicide based on monoterpene 1,4 cineole. Used as selective pre-emergence herbicide to control annual grasses. Inhibits mitosis in meristematic regions.

Front 34

Leptospermone

Back 34

Chemical found in lemon bottlebrush and Manuka which targets the HPPD enzyme involved in the biosynthesis of quinones and tocopherols. Therefore carotenoid biosynthesis interrupted and plants look white. Used to form herbicides to control broadleaf weeds and crabgrass

Front 35

Hormesis

Back 35

The idea that compounds can have a dual role either stimulatory at low doses or inhibitory at high doses

Front 36

Autotoxicity

Back 36

Release of chemicals by plants that affect their own growth. Ex: alfalfa, sunflowers, etc

Front 37

different ways that plants can defend themselves against herbivores

Back 37

mechanical or physical (structural, etc)- thorns or sap or thick cuticle, chemical- sap or poisons, behavioral (thigmonasty- movements that occur in response to touch), or evasive (mimicry/camouflage)