53 lines
3.1 KiB
Markdown
53 lines
3.1 KiB
Markdown
Procedure: Mosquito Pressure Experiment
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Purpose:
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To observe the effects of rapid air pressure changes on Culex pipiens (common mosquito) using a syringe as the experimental apparatus.
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Materials:
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1 sterile syringe (10 mL or larger, with a plunger and needle removed)
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3–5 live mosquitoes (Culex pipiens)
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Tweezers or small container for transferring mosquitoes
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Sterile gloves
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Magnifying glass or basic microscope for post-experiment examination
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Notebook and pen for documentation
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Procedure:
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Preparation of Syringe:
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Remove the needle from the syringe.
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Pull the plunger to create an open chamber in the syringe with minimal air pressure inside (roughly 5–7 mL of air space).
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Capturing Mosquitoes:
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Using tweezers or a small container, gently transfer 3–5 live mosquitoes into the syringe chamber.
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After the mosquitoes are inside, quickly cover the syringe opening to prevent escape.
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Initial Conditions:
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Hold the syringe vertically to allow the mosquitoes to settle.
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Take note of the mosquitoes' behavior and movement under normal air pressure conditions as a baseline.
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Experiment: Compression Phase:
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Slowly and steadily push the plunger inward, reducing the volume inside the syringe and increasing air pressure.
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Observe the mosquitoes’ behavior. Document any changes in movement, appearance, or visible damage.
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Stop compression when significant resistance is felt or until a critical volume is reached (~1 mL).
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Experiment: Decompression Phase:
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Rapidly pull the plunger back to its original position (~10 mL) to decompress the air inside the syringe.
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Watch for signs of immediate stress, including disorientation, reduced movement, or physical damage to the mosquitoes’ exoskeleton.
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Document changes in behavior and physical condition.
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Optional: Repeating the Cycle:
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If desired, repeat the compression-decompression cycle 2–3 more times to observe the cumulative effects of repeated pressure changes on the mosquitoes.
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Post-Experiment Examination:
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Once the experiment is complete, open the syringe and transfer the mosquitoes to a flat surface.
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Using a magnifying glass or basic microscope, inspect the mosquitoes for physical damage. Look for:
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Crushed exoskeletons
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Broken legs or wings
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Changes in internal structure (if visible)
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Record your observations in detail.
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Expected Observations:
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Compression Phase: Mosquitoes may exhibit signs of distress, disorientation, or reduced movement as the air pressure increases. Their exoskeleton may buckle or rupture under extreme pressure, leading to immediate death in some cases.
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Decompression Phase: Rapid decompression may cause the mosquitoes’ tracheal system (air-filled tubes for breathing) to collapse or rupture due to the expansion of gases. This may result in internal trauma and respiratory failure.
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Cumulative Effects: Multiple compression-decompression cycles can exacerbate physical damage and lead to certain death due to mechanical and respiratory trauma.
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Documentation:
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Record the starting air volume and the compressed volume for each phase.
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Note any visible physical damage to the mosquitoes after each pressure change.
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Provide a summary of the mosquitoes’ behavior throughout the experiment. |