Lecture 16: Plants as Chemical Factories Flashcards
True or False: The same plant may be poisonous, medicinal or even hallucinogenic depending on the dose
True
What are the two ways a substance could be secreted?
Remain deposited inside the secretory cell/tissue: for example, the laticifers.
They may be released from the secretory cell/tissue: for example, the resin ducts, secretory hairs.
Active ingredients” are usually ______
secondary metabolites.
______ secrete latex which is released only if the plant is cut or damaged. Laticifers usually form a 3D network in the entire plant
Laticifers
______ laticifers are composed of a series of cells joined together.
______ laticifers, consisting of one long cell.
Articulated
Non-articulated
Why does the plant secrete latex used for in laticifers?
At the slightest touch in this area (e.g. by an insect), the laticifers bursts and spays the “invader” with latex that has insecticide properties
True or False: Resin and gum ducts are present in all the organs of the plants: e.g. root, stems, leaves, inflorescences
True
the term gum duct is more commonly used with reference to ______ while resin ducts are employed more for _______.
Dicots,
Gymnosperms
True or False: Resin and gums have antimicrobial and antifungal properties and serve as an aid in the healing of plant wounds.
True
What is an example of a human use of resin ducts?
Incense being burnt
What are 3 plant examples that have secretory cavities?
Hypericum perforatum (St John’s wort)
Eucalyptus,
Ginkgo, etc.
True or False: Secretory cavities usually have antiviral, antibacterial, and antifungal properties
True
What family of plants is characterised by the presence of secretory cavities?
Apiaceae (ie, anise, caraway, carrot, celery, chervil, )
True or False: With secretory hairs, most have insecticide, antiviral, antibacterial, and antifungal properties.
True
In Cannabis, glandular hairs secrete ______ and _____.
cannabidoids, terpenoids
What are the compounds in stinging hairs?
formic acid in combination with histamine, acetylcholine, 5-hydroxytryptamine, and even serotonin
What is the pathogenesis of a stinging plant such as Uritica?
The tip of the stinging hair is brittle and breaks off upon slight contact, leaving a sharp point that readily pierces skin and allows fluid contents of the hair to enter flesh through the body of the hair, which acts as a miniature hypodermic needle
In the ______ family, secretory hairs secrete essential oils, which are volatile.
Lamiaceae (mint family)
True or False: The mint family (Lamiaceae) has antiviral, antibacterial, and antifungal properties.
True
_____ in general they contain N, they taste bitter, they have a marked physiological effect on insects and animals, especially on the nervous system, and have a anti-herbivory role
Alkaloids
What are examples of alkaloids?
caffeine, nicotine, morphine, ephedrine, quinine.
______ are very diverse chemically but generally they have a sugar molecule attached to the active component.
Glycosides
_______ glycosides release cyanide (HCN). No medicinal use.
_______ glycosides have a steroidal nucleus. Act on the heart muscle.
_______ have a also a steroidal nucleus. Give a froth when shaken with water. Various effects: expectorant, anti-inflammatory, phytohormones, and hemolysis of red blood cells.
______ glycosides: e.g. salicin with analgesic, antipyretic, and anti-inflammatory effects. Salicylic acid is a plant hormone.
Cyanogenic
Cardiac
Saponins
Alcoholic
What are the 4 characteristics of tannins?
Astringent, bitter, polyphenolic compounds that bind to and precipitate proteins.
Their function in plants is aid in the healing of wounds, and have antiviral, antibacterial and antifungal action.
Present in the wood, bark and many other tissues.
For us they have antioxidant and anti-inflammatory effect
_____ are complex carbohydrates, have same functions as the tannins and they are secreted in canals or ducts
Resins
______ are concentrated hydrophobic fluids containing volatile compounds
Defense against viruses, bacteria and fungi
Essential Oils (LAMIACEAE)
True or False: Resins are water insoluble and thus render any surface impervious to moisture.
True
Question: One of the following chemicals is not a alkaloid:
A: E saline
Q: What is the role of alkaloids in plants?
A: D They provide a defense against animal and insect herbivores
