General Herbicide Physiology Questions

Front 1

What are dicots?

Back 1

Dicotyledons are a group of flowering plants whose seed typically has two embryonic leaves (or cotelydons) with around 199,350 species including canola.

Front 2

What are phytohormones?

Back 2

These are plant hormones, chemicals that regulate plant growth and occur in extremely low concentrations. these hormones determine the formation of flowers, stems, leaves, the shedding of leaves, and the development and ripening of fruit.

Front 3

What are auxins?

Back 3

They are a class of phytohormone that coordinate many growth and behavioural processes in the plant life cycle.

Front 4

What are tropic responses?

Back 4

They are a biological phenomenon, indicating growth or turning movement of a biological organism (usually a plant) in response to an environmental stimulus where an organism is capable of directed physical movement. This response is dependent on the direction of the stimulus.

Examples would be movement or growth in responses to gravity, sunlight, water, temperature, etc.

Front 5

What is phyllotaxy?

Back 5

The arrangement of leaves on a plant stem.

Front 6

What is micropropagation?

Back 6

It is the practice of rapidly multiplying stock plant material to produce a large number of progeny, using modern plant tissue culture methods.

Front 7

What are transgenic plants?

Back 7

They are also known as GMO's and are plants whose genetic material has been altered using genetic engineering techniques. These techniques, generally known as recombinant DNA technology, use DNA molecules from different sources, which are combined into one molecule to create a new set of genes. This DNA is then transferred into an organism, giving it modified or novel genes.

Front 8

What does concomitantly mean?

Back 8

At the same time as.

Front 9

What is ABA?

Back 9

Also known as abscisic acid, abscisin II and dormin, it is a plant hormone that functions in many plant developmental processes, including bud dormancy. ABA-mediated signalling also plays an important part in plant responses to environmental stress and plant pathogens.

Front 10

What is an F-box protein?

Back 10

A protein that contains at least one F-box domain. The F-box domain is a protein structural motif of about 50 amino acids that mediates protein-protein interactions.

Front 11

What is a protein?

Back 11

Also known as a polypeptide, it is an organic compound made of amino acids arranged in a linear chain folded into a globular form. The amino acids in a polymer are joined together by the peptide bonds between the carboxyl and amino groups of adjacent amino acid residues.

Front 12

What are ligands?

Back 12

They are ins or molecules that binds to a central metal atom to form a coordination complex.

Front 13

What are proteasoms?

Back 13

Very large protein complexes inside all eukaryotes and archaea, and in some bacteria. The main function of the proteasome is to degrade unneeded or damaged proteins by proteolysis, a chemical reaction that breaks down peptide bonds.

Front 14

What is ubiquitin?

Back 14

It is a small regulatory protein that has been found in almost all tissues of eukaryotic organisms. Among other functions, it directs proteins to recycling.

Front 15

What is ACC?

Back 15

The chemical name 1-Aminocyclopropane-1-carboxylic acid is a disubstituted cyclic alpha-amino acid in which a three-membered cyclopropane ring is fused to the C(alpha)-atom of the amino acid. It plays an important role in the biosynthesis of the plant hormone ethylene. it is synthesized by the enzyme ACC synthase from methionine and converted to ethylene by ACC oxidase.

Front 16

What does ethylene do for a plant?

Back 16

It is a gaseous hormone that is involved in plant responses to stress and the regulation of senescence and plant growth.

Front 17

Define concomitant:

Back 17

A phenomenon that naturally accompanies or follows something (ie. some of us look on pain and illness as concomitants of the stresses of living).

Front 18

Define ubiquitous:

Back 18

Present, appearing, or found everywhere (ie. cowboy hats are ubiquitous among dipshits).

Front 19

What is quinclorac?

Back 19

It is a selective auxin herbicide which controls dicot weeds, but additionally controls important grass weeds, such as Echinochloa, Digitaria, Setaria and Brachiaria spp. in rice.

Front 20

What is a broad-leafed weed?

Back 20

Broad-leaf weeds are perennials, which means they live for more than one year. The tops may die back but the roots persist. These weeds produce large numbers of seeds capable of dispersing over great distances.

Front 21

What is a graminicide?

Back 21

Any herbicide designed to control weedy greases.

Front 22

What is esterification?

Back 22

It is a chemical reaction in which two reactants (typically and alcohol and an acid) form an ester as the reaction product.

Front 23

What is a metabolite?

Back 23

It is either a substance produced by metabolism, or a substance necessary for or taking part in a particular metabolic process.

Front 24

What is a cis isomer?

Back 24

From organic chemistry, cis means "on the same side", so cis isomer has its functional isomers on the same side.

Front 25

What is a trans isomer?

Back 25

From organic chemistry, trans means "on the other side", so a trans isomer has its functional isomers on opposite sides.

Front 26

What are lipids?

Back 26

They are a broad group of naturally occurring molecules which includes fats, waxes, sterols, etc. The main biological function of lipids include energy storage, as structural components of cell membranes, and as important signalling molecules.

Front 27

What are plastids?

Back 27

Plastids are major organelles found in the cells of plants and algae. Platstids are the site of manufacture and storage of important chemical compounds used by the cell.

Front 28

What is a chiral molecule?

Back 28

It is a type of molecule that lacks an internal plane of symmetry and has a non-superposable mirror image.

The feature that is most often the cause of chirality in molecules is the presence of an asymmetric carbon atom.

Think: Your right hand is chiral to your left hand.

Front 29

What is an enantiomer?

Back 29

It is one of two stereoisomers that are mirror images of each other that are "non-superposable"

Much as one's left and right hads are "the same" but opposite.

Front 30

What is pyruvate?

Back 30

The carboxylate ion of pyruvic acid it is a key intersection in several metabolic pathways.

Front 31

What is a eukaryotic organism?

Back 31

An organism whose cells contain complex structures enclosed within membranes.

They represent a tiny minority of all living things.

Front 32

What is a prokaryotic organisms?

Back 32

A group of organisms that lack a cell nucleus or any other membrane-bound organelles.

Front 33

What is transamination?

Back 33

There are two chemical reactions, the first is the reaction between an amino acid and an alpha-keto acid. The amino group is transferred from the former to the latter; this results in the amino acid being converted to the corresponding alpha-keto acid, while the reactant alpha-keto acid is converted to the corresponding amino acid.

This process is an important step in the synthesis of some non-essential amino acids that are not supplied from the diet.

Front 34

What are ways that humans can aid in the selection for herbicide resistance in weeds?

Back 34

By using herbicides that have a residual soil activity.

Front 35

What are ways that herbicide resistance can be delayed?

Back 35

Rotation of herbicides with herbicides from other chemical groups;

Choosing herbicides that are less persistent;

Skipping an in-crop herbicide application and depending more on the competitive nature of the crop to suppress weeds.

Front 36

What is a zwitterion?

Back 36

A zwitterion is a molecule with a positive and a negative electrical charge on different atoms s within the molecule.

Front 37

What do surfactants do?

Back 37

They influence the uptake of the herbicide.

Front 38

What is the transport molecule in the phloem?

Back 38

Carbon. If the carbon flow of sugars to the phloem is reduced, then the phloem transport in general is depressed.

This can cause herbicides to become trapped in a plants leaves.

Front 39

What is chlorosis?

Back 39

Chlorosis is a condition in which leaves produce insufficient chlorophyll, leaving leaves pale, yellow, or yellow white.

The affected plant has little or no ability to manufacture carbohydrates through photosynthesis and will die unless the cause of its chlorophyll insufficiency is treated.

Front 40

What is a phragmoplast?

Back 40

It is a plant cell specific structure that forms late during cytokinesis. It serves as a scaffold for cell plate assembly and subsequent formation of a new cell wall separating the two daughter cells.

It is a complex assembly of microtubules, microfilaments, and endoplasmic reticulum elements.

Front 41

Define sorption.

Back 41

Refers to the action of absorption or adsorption.

Front 42

Define entropy.

Back 42

It is a thermodynamic property that is a measure of the energy not available for use in a thermodynamic process, such as energy conversion devices, engines, or machines.

Front 43

If the K[OW] is a high number it is _____, if it is a low number it is _____.

Back 43

Hydrophobic, hydrophilic

Front 44

If the K[OC] is large then what does this generally mean for a herbicides ability to bind to the soil?

Back 44

Its ability to bind tightly to the soil.

Front 45

What is heterosis?

Back 45

Also known as outbreeding enhancement, it is the increased function of any biological quality in a hybrid offspring. It is the occurrence of a genetically superior offspring from mixing the genes of its parents.