Micro CHP1

What is microbiology?

The study of tiny living things you can't see without a microscope.

What are the major groups of microorganisms?

Bacteria

viruses

fungi (like mold)

protozoa (tiny single-cell critters)

algae

and worms (helminths).

Real life: Anytime you hear "germs," you're hearing about microbiology.

What are the main jobs/areas in microbiology?

Medical Microbiology / Public Health / Epidemiology– studies germs and human sickness

Biotech/Industrial – uses germs to make stuff (like vaccines, beer) Immunology – studies how our body fights germs

Agricultural – germs and farm plants/animals Food – germs in our food (spoilage, food poisoning, making cheese/yogurt) Real life: The CDC tracking a disease outbreak = medical microbiology.

What's a prokaryotic cell?

A simple cell with no nucleus. (Bacteria are like this.)

What's a eukaryotic cell?

A cell (can be single or multi- cell) with a nucleus and other tiny parts inside (organelles). (Your cells are like this — and so are fungi, protozoa.)

Which came first?

Prokaryotes — they've been around about 3.5 billion years, way before eukaryotes. Real life: Antibiotics kill bacteria (prokaryotes) but don't hurt your cells (eukaryotes) — that's why they work.

What two big jobs do microbes do for Earth?

Photosynthesis – make oxygen and food from sunlight (over half of all photosynthesis on Earth is done by microbes!)

Decomposition – break down dead stuff and recycle nutrients back into nature

Real life: Ocean algae make about half the air you breathe.

What's the size order, smallest to biggest?

Viruses < bacteria (prokaryotes) < eukaryotic cells

How are viruses different from real cells?

Viruses aren't cells at all. They only have DNA or RNA (never both), and they can't reproduce on their own — they need to hijack another cell to copy themselves. Real life: This is why antibiotics don't work on colds/flu (viruses) — there's no cell there to attack.

What are 3 ways we use microbes?

Food – bread, cheese, alcohol Biotech – making medicine, vaccines, GMO crops Bioremediation – using microbes to clean up pollution (like oil spills) Real life: Insulin for diabetics is made using bacteria (biotech).

What's a parasite?

An organism that lives on or in the body of another organism (the host) and is harmful to that host.

What's a pathogen?

A germ that causes disease.

Are most germs bad?

No! Most microbes are harmless or even helpful. Only some cause disease. Real life: HPV (a virus) can cause cervical cancer — that's why there's a vaccine for it.

Who first saw microbes under a microscope?

Leeuwenhoek.

Who proved germs don't just "pop up" from nothing (proved biogenesis, not spontaneous generation)?

Louis Pasteur. He also invented pasteurization and made vaccines.

Who made the rules (postulates) to prove a germ causes a disease?

Robert Koch.

Who taught us that washing hands stops the spread of germs?

Dr. Semmelweis (physicians going from autopsies to delivering babies without washing hands = more infections). Joseph Lister then brought this into surgery. Real life: Your handwashing lab this week is literally testing Semmelweis's discovery!

What's a hypothesis?

A guess that can be tested.

What's a theory?

A hypothesis that has TONS of evidence backing it up. It's not just a guess — it's strongly supported. Real life: "Germ Theory of Disease" isn't a guess — it's backed by a mountain of proof.

Why can't we just use common names like "cougar"?

Because one animal can have many different common names (cougar, puma, mountain lion — all the same animal!). Confusing.

How do scientific names work?

Two parts: Genus + species. Example: Panthera concolor Always italicized Genus is capitalized, species is lowercase Can shorten genus: P. concolor

What is evolution?

How new species form from older species over time. All living things share a common ancestor.

What drives evolution?

Natural selection — organisms best suited to their environment survive and have more babies.

What are the 3 Domains?

Bacteria – true bacteria Archaea – "weird" bacteria that live in extreme places (like hot springs) Eukarya – everything with a nucleus (that includes us!)