Test I Material Flashcards
What are the three domains in the tree of life?
Bacteria, archaea and eukarya
What is the definition of a microbe?
Something too small to see with the naked eye
Why does the definition of microbe have some inaccuracy?
Some microorganisms can grow big enough to see with the naked eye
What is “oxygenic photosynthesis”? What process did this enable?
Photosynthesis that produces oxygen. It allowed single-cell organisms to become stronger and have the potential for multi-cell aggregation.
What is “Lokiarchaeum”? Why is it important?
An Archaean that resembles a eukaryote. In many ways, archaea is more similar to eukarya than bacteria are.
What is the percentage similarity between “Lokiarchaeum” and eukaryotes? What is a way they are similar?
3% commonality. They both produce some protein products unique to eukaryotes, such as actin.
What was an initial hypothesis for the first eukaryotes? With the new information about cell membranes, what is a new theory?
People thought a bacteria could have gone into an archaean to live in symbiosis, eventually forming a new type of life. However, the cell membrane of archaea is unlike eukarya… therefore, it is more likely that a bacteria absorbed an archaean and took on some of its characteristics before joining with the mitochondria-bac.
Why does aerobic respiration make cells strong? What does it increase?
Oxygen is a good terminal electron acceptor because it is a strong oxidizing agent. This increases the “proton motive force” so that the organisms will be stronger.
What kind of bacteria may have become a mitochondrion?
Alphaproteobacteria
What kind of bacteria may have become a chloroplast? Why?
Cyanobacteria. They use the same pathways for photosynthesis as plants with chloroplasts.
How are biofilms similar to multicell organisms?
They give cells a place to live in community. Even though they are microbes, they live in symbiosis with nutrients, protection and movement.
TRUE OR FALSE: Biofilms may only contain one species of bacteria
False! They can contain multiple species. Even within the same species, they can be differentiated into specific “jobs”
What is genetic diversity? How does it affect bacteria and other microbes?
Genetic diversity is the uniqueness of individual cells, both in genetic makeup and gene expression.
What are the three types of E. coli? What percentage similarity do they have?
Nonpathogenic (lab cells), uropathogenic (urinary tract infections) and enterohoemorrhagic (diarrhea, stomach bug). 40% similarity between them.
What is nutrient cycling?
Microbes processing foods in the gut, like cellulose-digesting bacteria in cow stomachs. Even some in human stomachs!
