Bacteria
Life Processes ... continued
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Nutrition
The best clip of how the life of decay feeds back into food chains
Autotrophs
Autotrophs make everything
Autotrophs eat nothing
Autotrophs atoms come from the air
Autotrophs are the beginning
Autotrophs take Water and Carbon dioxide, they use the energy of the Sun to fuse these together, creating Sugar and excreting Oxygen
The atoms of this sugar are then rearranged and used to make everything else
The first Autotrophs were Bacteria, Cyanobacteria.
Heterotrophs
Everything that can not make its own food from photosynthesis must then eat it
Everything that eats, including us, are heterotrophs
Extracellular Digestion
Bacteria eat by releasing releasing digestive enzymes into their environment
These digestive enzymes diffuse away from the bacteria and arrive at large nutrients like cellulose
They then cut up the large nutrients into small soluble molecules like sugar
These nutrients then diffuse towards the bacteria and either diffuse across the cell membrane or are transported across using channels. These channels either operate through passive diffusion and just facilitate the diffusion (facilitated transport) or they use some ATP to actively facilitate the movement of nutrients (active transport)
Types of Heterotrophs
Saprotroph
Saprotrophs eat DEAD stuff
They are responsible for Decomposition and the cycling of Carbon and Nitrogen back into the Atmosphere
Sapro = putrid. Troph = food
Decomposition and Decay
3 Types of Bacterial Guests for the living to Host
Parasitic
These are the uninvited guests.
You do not want them there
Parasitic bacteria feed off living things
The human blood and the spaces between cells are rich in nutrients that are on their way to the human cells. If bacteria can get into the spaces between the cells then they can eat these nutrients before the human cells can.
This is why you need to clean and cover any cuts
This is also the main reason why you get bacterial skin sores. Basically bacteria are feeding off the nutrients that were on their way to feed your skin cells.
This causes harm, because they are stopping the nutrients from getting to your cells, effectively starving your cells
The immune system will respond, and attack and kill of the bacteria
However, some very bad bacteria make toxins that will kill human cells. Anthrax toxins kill cells, they kill the immune system, and ultimately they kill the 'host' organism.
Most parasitic bacteria are also pathogenic
A parasite feeds off a host
A pathogen makes a host sick
Mutualistic
Mutualistic means mutually beneficial
A bacterial version of 'I scratch your back you scratch mine'
Our Gut bacteria is a perfect example of this.
We give our gut bacteria food in the form of fiber, they give us Vitamins and Short Chain Fatty Acids (very healthy fatty acids)
Communalistic
Communal 'eating off the same table'
It is one sided, one benefits, the other doesn't benefit.
The bacteria of our skin is communalistic. They don't give us anything in return for all the food and 'land' that we give them.
However their presence means that pathogenic bacteria can't colonize your skin as there is no space of food left for them. So there is a slight benefit which is why our immune system ignores them as long as they stay on their side of the skin
Opportunistic Pathogens
Some Communalistic bacteria can become pathogens if the immune system is compromised and can no longer keep them in check due to it being busy with another infection or aliment or even stress
Overview
