### substance | humectant:

Propylene glycol
* is antifreeze
  - approved in nearly all states
  - chemical compounds
  - employed as a hygroscopic agent for tobacco
  - metabolized to lactic and pyruvic acids through aldehyde intermediates
  - practically odorless and tasteless
  - still poisonous, but far less so than conventional antifreeze
* is used extensively for commercial and industrial purposes
  - in food additives
  - to extract flavor from natural flavoring materials

Husk
* Some husks cover ears.
* are sheaths.
* help retain freshness and sweetness.
* start out green, sticky, and fuzzy and become dark brown with age.

### substance | husk:

Bract
* are highly modified leaves that surround the main structure of the flower
  - husks
  - leaves associated with flowers
  - membranous, ovate, acuminate, and mauve in color
  - part of inflorescences
  - small, bearing some reduced tentacles
  - susceptible to sunburn if exposed to high light intensities at finish
  - usually a blood-red, crimson, yellow, pink, or color
  - woody parts, resembling scales, under flowers similar to the scales of a pine cone
* emerge about two weeks before flowers and give leafy spurge the appearance of flowering.
* exude milky-sap that is irritating and toxic.
* look much like scales, but bracts occur wherever a flower's pedicel attaches to the peduncle.
* occur where the leaf petioles attach to the stem.
* subtending the female flowers contain a greater density of glands than the leaves.
* vary enormously in size, shape and function.

Pea pod
* are legumes
  - part of peas
  - pods
* lose their crispness if overcooked.

Psyllium husk
* are pure dietary fiber, composed mostly of hemicellulose.
* is non-allergenic and the ultimate quality soluble fiber.
* source of dietary fiber.

Hyaline
* cartilage overlying lamellar bone.
* contains very little elastin compared to elastic cartilage.

Hydrocolloid
* Many hydrocolloids are derived from natural sources.
* Some hydrocolloids have a claim for moderately exuding wounds.
* also have the advantage of being strong and flexible.
* are substances
  - useful in the prevention of pressure areas
* serve a variety of functions.

Hydrophilic substance
* Most hydrophilic substances mix with water.
* dissolve readily and easily in water.
* have an affinity for water.
* have an easier time passing through membranes than do hydrophobic substances
  - membranes than hydrophobic substances do

### substance:

Inhibitor
* Some inhibitors make the plant leaves fall off in the Autumn.
* are hazardous during pregnancy
  - hormones that inhibit plant growth
  - of two different types
* are substances capable of inhibiting or suppressing chemical reactions
  - which diminish the activity of an enzyme
  - suspected when an increase in the frequency of bleeding occurs
  - the body s way of fighting off what it sees as a foreign agent
* can bind the the enzyme and slow it down or stop it completely.
* cause the allosteric enzyme to adopt the inactive shape.
* delay the transformation from ammonium to nitrate.
* frequently act on the recipient host rather than on the virus itself.
* interfere with enzyme function.
* restrain growth and maintain the period of dormancy in seeds and buds.
* slow the rate of reaction, sometimes even stopping the reaction completely.
* stop all radical polymerization until consumed.
* usually increase concentrations of other drugs.
+ Catalysis
  * There are many catalysts in our body which play an important part in many biochemical reactions. These are called enzymes. Most catalysts work by lowering the 'activation energy' of a reaction. This allows less energy to be used, thus speeding up the reaction. The opposite of a catalyst is an 'inhibitor'. Inhibitors slow down reactions. Some of them are found in snake venom and are dangerous for our nervous system or heart.