Bio 80 Exam 2
Prokaryotes and Nutrient cyclers
- Convert some molecules so it can be taken up by other organisms.
- Cyanobacteria and other autotrophic prokaryotes use CO2 to make organic compounds such as sugars, which are then passed through the food chain.
- Cyanobacteria produce atmospheric O2 and others prokaryotes fix atmospheric nitrogen (N2) into forms that other organisms can use to make the building blocks of proteins and nucleic acids
- Increase the availability of nutrients that plants require for growth, such as nitrogen,phosphorus and potassium.
- Can decrease the amount of key plant nutrients, occurs when nutrients are immobilized by using them to synthesize molecules than remain within their cells. (Effect on soil nutrient concentration )
Prokaryotes and Pathogens
Parasitism an ecological relationship in which a parasite eats the cell content tissues, or bodily fluids of its host. Parasites that causes diseases are called pathogens.
- All pathogens known to date are bacteria. Bacteria cause about half of all human diseases.
- Pathogens prokaryotes usually cause illness by producing poisons, which are classified as exotoxins or endotoxins.
- Exotoxins are proteins secreted by certain bacteria and other organisms cholera, a diarrheal diseases caused by exotoxins
- Endotoxins are lipopolysaccharide components of the outer membrane of gram-negative bacteria, released only when the bacteria die and their cells wall break down. Salmonella
Prokaryotes and Mutualists
Mutualism an ecological interaction between to species in which both benefit.
- Intestine are home to an estimated 500-1000 bacteria , they vary in their ability to process different foods.
- They digest foods our intestines cannot break down.
- The gut mutualist, include a large array of genes involved in synthesizing carbohydrates , vitamins, and other nutrient needed for humans.
Prokaryotes and decomposers
Prokaryotes play a major role in the process of recycling of chemical elements between the living and the nonliving components of an ecosystems.
- Chemoheterotrophs prokaryotes function as decomposers, breaking down dead organisms as wells as waste products and thereby unlocking supplies of of carbon, nitrogen, and other elements