What are Microbes?

Also called prokaryotes – Domains Bacteria and Archaea

Microbes Microbes lived alone on Earth for over 1 billion years – Most numerous and widespread organisms on Earth More bacteria live in your mouth than the total number of humans that have ever lived! There are ten times as many bacteria living in and on your body as the number of cells in your body! Pin PointBacteria

What do microbes do on Earth? – Although some bacteria can cause disease, most bacteria on our bodies are neutral/beneficial –Decompose dead skin cells –Supply essential vitamins –Guard against pathogenic organisms – Prokaryotes in soil decompose dead organisms, sustaining chemical cycles

How small is a microbe? Vary between 0.1 to 10 μm

What does a microbe look like?

Microbe Parts Flagella and cilia – Aid in movement Membrane and Envelope – Aid in enclosure and protection Plasma membrane Rotary movement of each flagellum Flagellum Cell wall Motility

Tardigrades Small microscopic organisms ranging from mm Can survive extreme temperatures from -273 º C to 151 º C Can go a decade without water Tardigrade

Tardigrades in Space Were sent to space for 10 days where the sun’s UV rays were 1000x stronger Majority survived and reproduced successfully First creature ever known to survive open space

How fast do bacteria grow? Bacterial Growth

Bacterial Growth Model When do bacteria double in number? At every Time Step (TS)  every 20 minutes Bacteria current TS = 2 x Bacteria previous TS

Notations What does Bacteria current TS mean? Bacteria current TS is the number of bacteria at the current time step

Let’s look at bacterial growth! You will start with 1 bacteria When time is called, you will double the amount of bacteria Record the amount of bacteria present at each Time Step

Time Step Bacteria Bacteria current TS = 2 x Bacteria previous TS