# GTBOP Moodle Matching Exercises
## Principles of Insecticide Mode of Action — Dr. Michael Scharf

**Webinar Date:** October 18, 2017
**Series:** Structural Pest Control
**Activity Type:** Matching Exercises
**Exercises:** 3
**Total Pairs:** 26 (8 + 10 + 8)

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### CHAIN OF CUSTODY
- **Source documents:** Corrected SRT (GTBOP_Transcript_2017-10-18_InsecticideMOA.srt) + Archive Package (GTBOP_Archive_Summary_2017-10-18_InsecticideMOA.md)
- **All terms, definitions, and relationships derived exclusively from presentation content**

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### Matching Exercise 1: Insecticide Classes and Their Target Sites
**Timestamp Reference:** 28:40 – 39:05 (primary coverage area)
**Type:** Product-Target Site Matching

**Instructions:** Match each insecticide class in Column A with the target site it affects in Column B. Note: Column B contains two extra items.

| # | Column A | | Column B |
|---|----------|-|----------|
| 1 | Pyrethroids | | a) Chloride channels |
| 2 | Fipronil (phenylpyrazole) | | b) Acetylcholine receptor |
| 3 | Nicotinoids | | c) Muscular calcium channels |
| 4 | Organophosphates and carbamates | | d) Axonal sodium channels |
| 5 | Diamides (chlorantraniliprole) | | e) Acetylcholinesterase enzyme |
| 6 | Indoxacarb (oxadiazine) | | f) Mitochondria (energy production) |
| 7 | Abamectin (avermectin) | | g) Chitin synthesis enzymes |
| 8 | Chitin synthesis inhibitors | | h) Glutamate-gated chloride channels |
|   |   | | i) Juvenile hormone receptors |
|   |   | | j) Axonal sodium channels (blockage) |

**Answer Key:**
1 → d, 2 → a, 3 → b, 4 → e, 5 → c, 6 → j, 7 → h, 8 → g

**Notes:**
- Items 1 and 6 both target sodium channels but through opposite mechanisms (stimulation vs. blockage), which is why they map to separate entries (d and j). This distinction is a key teaching point from the presentation.
- Distractors: (f) mitochondria and (i) juvenile hormone receptors are legitimate target sites discussed elsewhere in the presentation but do not match the classes listed in Column A.

**Source in transcript:** Blocks 301–343 (target site roadmap), 346–362 (sodium channels), 363–387 (chloride channels), 388–407 (acetylcholine), 429–444 (diamides), 466–482 (IGRs)

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### Matching Exercise 2: Insecticide Mode of Action Effects
**Timestamp Reference:** 17:51 – 47:00 (spans full classification section)
**Type:** Product-Effect Matching

**Instructions:** Match each insecticide or insecticide class in Column A with the physiological effect it produces in insects, as described by Dr. Scharf, in Column B. Note: Column B contains two extra items.

| # | Column A | | Column B |
|---|----------|-|----------|
| 1 | Pyrethroids / pyrethrins | | a) Blocks chloride channels, causing nervous system excitation |
| 2 | Fipronil | | b) Stimulates muscular calcium channels, causing contraction followed by energy depletion and paralysis |
| 3 | Indoxacarb | | c) Stimulates sodium channels, causing rapid knockdown and excitation |
| 4 | Organophosphates | | d) Inhibits chitin synthesis enzyme, causing death during molting |
| 5 | Diamides | | e) Blocks sodium channels, causing paralysis ("on switch stuck in off position") |
| 6 | Juvenile hormone analogs (pyriproxyfen) | | f) Inhibits acetylcholinesterase, causing excitation from neurotransmitter buildup |
| 7 | Chitin synthesis inhibitors | | g) Mimics juvenile hormone, causing cuticle deformation and extra juvenile stages |
| 8 | Abamectin | | h) Stimulates chloride channels, causing inhibition and paralysis |
| 9 | Silica gel / diatomaceous earth | | i) Abrades waxy cuticle layer, causing water loss and dehydration |
| 10 | Nicotinoid-pyrethroid combinations | | j) Stimulates acetylcholine receptors and sodium channels simultaneously (potentiation) |
|   |   | | k) Disrupts mitochondrial respiration, depleting cellular energy |
|   |   | | l) Blocks acetylcholine receptors, preventing nerve signal transmission |

**Answer Key:**
1 → c, 2 → a, 3 → e, 4 → f, 5 → b, 6 → g, 7 → d, 8 → h, 9 → i, 10 → j

**Notes:**
- This exercise tests understanding of both the target site AND the specific mode of action (stimulation vs. blockage vs. inhibition) — the core teaching framework of the presentation.
- Distractors: (k) mitochondrial disruption is discussed for products like hydramethylnon but is not paired with any Column A item; (l) is a plausible-sounding but incorrect mechanism not described in the presentation.

**Source in transcript:** Blocks 184–205 (four modes of action), 346–362 (sodium channels), 363–387 (chloride channels), 388–407 (acetylcholine), 408–420 (combinations), 429–444 (diamides), 466–482 (IGRs), 499–511 (dusts)

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### Matching Exercise 3: Practical Factors Affecting Insecticide Performance
**Timestamp Reference:** 48:15 – 56:30 (practical factors section)
**Type:** Timing-Practice Matching

**Instructions:** Match each practical factor or scenario in Column A with the correct explanation or outcome described by Dr. Scharf in Column B. Note: Column B contains two extra items.

| # | Column A | | Column B |
|---|----------|-|----------|
| 1 | Excess food in a cockroach account | | a) Can pass insecticide through two digestive tracts and still affect a third individual |
| 2 | Dirt and grease on treated surfaces | | b) Physically bind and tie up insecticides, reducing their effectiveness |
| 3 | Cockroach secondary/tertiary kill | | c) Enables slow-acting insecticides to spread through food sharing and grooming |
| 4 | Trophallaxis and allogrooming in social insects | | d) Competes directly with bait placements, reducing consumption by target pests |
| 5 | Flea larvae exposed through adult flea feces | | e) Causes the insecticide's active ingredient to degrade faster in the environment |
| 6 | UV light exposure on raw insecticides | | f) Larvae consume insecticide-laden feces of treated adults as a nutritional source |
| 7 | Formulations (inerts, stabilizers, attractants) | | g) Enhance stability, extend longevity, improve safety, and keep active ingredients dissolved in water |
| 8 | Product rotation every 3 months or monthly | | h) Helps manage resistance by alternating between different modes of action |
|   |   | | i) Increases the LD50 of the product, making it less toxic to target pests |
|   |   | | j) Converts neurotoxic insecticides into non-repellent formulations |

**Answer Key:**
1 → d, 2 → b, 3 → a, 4 → c, 5 → f, 6 → e, 7 → g, 8 → h

**Notes:**
- This exercise bridges the gap between toxicology and practice — the section of the presentation Scharf described as "where toxicology interfaces with practice."
- Distractors: (i) is plausible-sounding but reverses the relationship (formulations don't increase LD50 for targets); (j) is a fabricated mechanism not described in the presentation.

**Source in transcript:** Blocks 515–547 (stability and formulations), 548–567 (pest behavior), 568–585 (sanitation), 586–611 (resistance management)

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## Moodle Activity Verification

- [x] All terms, definitions, and relationships derived from presentation content
- [x] Timestamp references verified against corrected SRT
- [x] No external knowledge required to answer correctly
- [x] Matching items unambiguous based on presentation content
- [x] 1–2 plausible distractors included per exercise to prevent elimination guessing
- [x] Answer keys unambiguously correct per speaker's content
- [x] Exercises cover early (target sites), middle (modes of action and effects), and late (practical factors) presentation content