17: Plant Poisons and Medicines Flashcards
How was quinine developed from traditional medicine?
Indigenous use of fever bark shared with Jesuits → isolation of quinine → anti-malarial drug.
How does capsaicin affect mammals and birds?
Irritates mammalian nerves (defence); birds tolerate it—likely due to no molars.
What is the mechanism of digitalis glycosides like digoxin?
Slows/strengthens heart rate. Narrow therapeutic range—small overdoses can be toxic.
How does ricin exert its toxic effect?
A chain inhibits ribosomes (blocks protein synthesis); B chain helps cell entry → cell death.
What is the therapeutic range?
The dose range between effective treatment and toxic effect. Crucial for safe plant medicine use.
How are pharmaceuticals regulated in Canada?
Require pre-clinical + clinical trials proving efficacy/safety.
How are Natural Health Products (NHPs) regulated in Canada?
Evidence from traditional use + scientific data.
Clinical trials not required.
How can a plant compound be both a spice and a medicine?
Capsaicin is used as both due to its irritant and muscle-relaxant properties.
Which of the following best defines plant secondary metabolites?
A. Compounds required for plant reproduction
B. Compounds involved in DNA replication
C. Compounds used for defence, attraction, or ecological functions
D. Primary sugars and carbohydrates
c. Compounds used for defence, attraction, or ecological functions
What plant compound is found in chilli peppers and used both as a spice and a muscle relaxant?
A. Ricin
B. Quinine
C. Capsaicin
D. Digoxin
C. Capsaicin
What determines whether a plant compound acts as a medicine or a poison?
the dosage
Which Canadian product requires full clinical trials for approval?
Pharmaceutical drugs
What is the toxic compound found in castor beans?
ricin
Which of the following describes the therapeutic range?
The range between an effective and a toxic dose
What historical plant use led to the discovery of aspirin?
Willow bark
