plpa quiz 4

Amanita phalloides (Death cap)

Deadly mushroom containing amatoxins that inhibit RNA polymerase II causing liver and kidney failure

Amanita muscaria (Fly agaric)

Hallucinogenic mushroom containing muscimol and ibotenic acid causing delirium and visions

Psilocybin mushrooms

Hallucinogenic mushrooms where psilocybin converts to psilocin affecting serotonin receptors

Gyromitra (false morels)

Toxic mushrooms containing gyromitrin which converts to MMH causing liver toxicity

Long symptom delay (mushrooms)

Indicates amatoxin poisoning and is often fatal

Short symptom onset (mushrooms)

Usually indicates mild GI toxins and less severe poisoning

Robert Hooke

First person to describe fungal structures and coin the term “cells”

Anton van Leeuwenhoek

First to observe bacteria and protozoa (“animalcules”) with 200–400× lenses

Animalcules

Term Leeuwenhoek used for bacteria and protozoa

Compound microscope

High-magnification microscope with objective and ocular lenses up to 1000×

Dissecting microscope

Low-magnification microscope (7–40×) used for large specimens

Magnification

Enlarging an image without necessarily improving detail

Resolution

Ability to distinguish two close objects as separate

Difference between magnification and resolution

Magnification makes things bigger; resolution makes them clearer and distinct

Oil immersion lens

Lens using oil to reduce light refraction and increase resolution

Oil immersion purpose

Reduces light refraction so more light enters lens creating a sharper

Spontaneous generation

Belief that life arises from nonliving matter through a “vital force”

Vital force argument

Idea that air contained mysterious force causing spontaneous generation

Francesco Redi

Disproved spontaneous generation for maggots using meat in open

Redi’s experiment

Showed maggots come from flies not meat by comparing open

John Needham

Supported spontaneous generation after broth became cloudy due to incomplete sterilization

Needham’s experiment

Claimed spontaneous generation after cloudy broth but failed due to incomplete sterilization

Lazzaro Spallanzani

Challenged Needham by boiling broth longer and sealing flasks to prevent growth

Spallanzani’s experiment

Disproved Needham by boiling broth longer and sealing flasks which prevented microbial growth

Louis Pasteur

Disproved spontaneous generation

Pasteur’s role in spontaneous generation

Finally disproved spontaneous generation with swan-neck flasks showing microbes come from air

Swan-neck flask experiment steps

Broth boiled → flask open to air with curved neck → microbes trapped in neck → broth stays sterile unless neck is removed

Swan-neck flask meaning

Demonstrated microbes originate from other microbes in air

Fermentation (Pasteur)

Process caused by living yeast cells producing alcohol

How fermentation works

Yeast converts sugars into alcohol; bacteria can convert sugars into acids causing souring

Germ Theory of Disease

Concept that microbes cause infectious diseases

Pasteurization

Heating beverages to kill pathogens and slow spoilage

Pasteurization prevents

Diseases like tuberculosis and spoilage bacteria in milk

Paul Ehrlich

Proposed “magic bullet” drug concept and created Salvarsan for syphilis

Magic bullet

Chemical that selectively targets microbes without harming the host

Antimicrobial agent

Substance that kills or inhibits microbes

Antibiotic

Antimicrobial used inside the body targeting bacteria

Antiseptic

Antimicrobial safe for living tissues like skin

Disinfectant

Chemical used on non-living surfaces too harsh for skin

Difference between disinfectant/antiseptic/antibiotic

Disinfectants = surfaces

Symptoms of amatoxin poisoning

Delayed vomiting

Yeast (Pasteur)

Living organism responsible for alcohol fermentation

Bacteria in wine

Responsible for spoilage and souring

Microscope resolution importance

Determines clarity and ability to distinguish details

Leeuwenhoek’s discoveries

First to observe living microbes including bacteria

Reason for gap after Leeuwenhoek’s death

His discoveries weren’t connected to disease or ecology