### acid:

Propionic acid
* fatty acid that exists naturally in everything from apples to wood pulp.
* is carboxylic acid
  - dangerous to skin and eyes and corrosive to farm equipment
* source of nutrition and is among the safest of all food additives.

Protein amino acid
* induces intense pain
* triggers reaction.

Pyruvic acid
* accumulates in the blood after consumption of the adulterated oil.
* is acid
  - chemical compounds
  - converted into carbon dioxide
  - electrolytes
  - liquids
  - organic acid
  - the main natural compound during the human metabolism process
* loses carbon dioxide and is converted to the two- carbon compound acetaldehyde.

Resin acid
* are composed of tricyclic diterpenoid carboxylic acids.
* undergoes anaerobic degradations

### acid:

Retinoic acid
* affects patterning along the anterior-posterior axis of the ascidian embryo
  - vegetal plate formation in sea urchin embryos
* can block differentiation of the myocardium after heart specification.
* causes the promyelocytic cells to be replaced by normal, mature cells.
* establishes ventral retinal characteristics.
* has a hormone-like action.
* induces embryonal carcinoma cells to differentiate into neurons and glial cells
  - polarizing activity but is unlikely to be a morphogen in the chick limb bud
* is also necessary for initiation of limb bud outgrowth
  - critical for proper development
  - involved in normal developmental alveolar growth and septation
* is known to be able to activate certain patterning genes in the limb bud
  - inhibit bone formation and to increase bone resorption
  - necessary for development of the ventral retina in zebrafish
  - such a tumor drug
* is the active form of vitamin A in the body
  - form of vitamin A that does all the work in the nucleus
* mimics the natural morphogen.
* popular topical treatment for acne, psoriasis, and other skin disorders.
* produces rod photoreceptor selective apoptosis in the developing mammalian retina.
* promotes photoreceptor differentiation in rat retinal cell cultures.
* regulates oral epithelial differentiation by two mechanisms.
* reverses ethanol induced cardiovascular abnormalities in quail emb ryos.
* seems to cause the cells to redifferentiate and then be able to take up iodine.

### acid:

Salicylic acid
* Some salicylic acids can upset the balance of the skin enough to cause problems durring waxing.
* can also be mixed with sulfur to treat dandruff
  - induce resistance to plant virus movement
* causes the destruction of the corn tissue.
* comes in many different forms and generic drug names.
* exfoliates dead flaky skin, reduces oil production and promotes healing.
* has a half life of about four hours at therapeutic doses
  - anti-inflammatory and antibacterial properties
* helps unclog pores and prevent abnormal shedding of skin cells.
* induces changes in the physical properties of model and native kidney membranes
  - of model and native membranes
  - also comedolytic
  - chemical compounds
  - derived from aspirin
  - keratolytic, keratoplastic, antipruritic, and bacteriostatic
  - particularly effective on blackheads
  - phenols
  - synthesized from the amino acid phenylalanine
* is the active ingredient in many acne treatments, and it also reduces inflammation
  - most acne products on the market
  - used in many top acne products on the market today, and proven acne fighter
* natural substance which is part of the defense mechanism of plants.
* offers keratoplastic, keratolytic, bacteriostatic and mild anti-pruritic functions.
* product used to make aspirin.
* relatively polar, poorly aqueous soluble material.
* works deep into the pores to clean the debris of dead cells.