4: Poisonous Challenges (toxins too!!)

Question 1

what is a poison/toxin?

Answer 1

any substance that disturbs homeostasis

Question 2

what are 3 entry points for poisons and what is an initial response to their consumption?

Answer 2

• ingestion via oral cavity -> vomiting, diarrhoea
• absorption via skin -> swelling
• inhalation via oral and nasal cavity -> sneezing, coughing

Question 3

what does toxicity level depend on?

Answer 3

dose and duration of exposure

Question 4

how long does an organism have to be exposed to a poison for it to be described as an acute effect?

Answer 4

less than one week

Question 5

how long does an organism have to be exposed to a poison for it to be described as a chronic exosure?

Answer 5

more than 3 months

Question 6

what are the origins of zootoxins?

Answer 6

animals

Question 7

what are the origins of phytotoxins?

Answer 7

plants

Question 8

what are the origins of endo-/exotoxins?

Answer 8

microbes

Question 9

what are the origins of mycotoxin?

Answer 9

fungi

Question 10

what is the rate of exposure of toxins determined by?

Answer 10

route of exposure

Question 11

what are poisonous principles?

Answer 11

compounds that make plants poisonous

Question 12

how many compounds are there in alkaloids?

Answer 12

4000

Question 13

how do animals detoxify alkaloids?

Answer 13

through their liver prior to excretion

Question 14

what is the alkaloid morphine used as?

Answer 14

Analgesia (pain relief)

Question 15

what are the 4 classifications of glycosides?

Answer 15

cyanogenic, goitrogenic, cardiac, saponins

Question 16

what happens if cyanogenic glycosides are consumed?

Answer 16

cyanide (CN) is converted to hydrogen cyanide (HCN) in an enzyme, this disrupts the body’s ability to use oxgen

Question 17

how do goitrogenic glycosides affect the body?

Answer 17

affects thyroid activity

Question 18

what trait prevents consumption of goitrogenic glycosides?

Answer 18

pungent flavour

Question 19

what effect do cardiac glycosides have on the body?

Answer 19

reduce heart rate

Question 20

what effect do saponin glycosides have on the body?

Answer 20

haemolyse red blood cells

Question 21

how does the consumption of nitrates affect the body?

Answer 21

nitrates converted to toxic nitrites, these form methaemoglobin, this causes poor O2 transport

Question 22

how do oxalates deplete Ca from the body?

Answer 22

the form insoluble calcium salts

Question 23

what are possible ways that pesticides can affect metabolism?

Answer 23

• neurotoxins
• anticoagulants (stop blood clots)
• gastrointestinal distress and dehydration
• hepatic (liver) stress and liver failure
• disruption of cellular ionic gradient

Question 24

what happens to excess minerals that are consumed?

specifically, effect on liver

Answer 24

accumulate in liver, which can cause failure of the liver

Question 25

what is the alkaloid quinidine used for?

Answer 25

Cardiac depressant

Question 26

What is the alkaloid lobeline used for?

Answer 26

Respiratory stimulant

Question 27

What is the alkaloid tubocurarine used for?

Answer 27

Muscle relaxant

Question 28

What is the alkaloid ergometrine used for?

Answer 28

vasoconstriction