Microbiology and Properties of Cellular Life Flashcards
What is microbiology?
The study of microorganisms
What are 5 study areas in microbiology?
- Microbial physiology (structure and function)
- Diversity and evolution of microbes
- Environmental roles of microbes
- Effects of microbes on other living things
- How we can use microbes in industrial processes
What are microorganisms?
Microscopic organisms that you can’t see with the naked eye. Includes prokaryotes, single-celled eukaryotes, and acellular microbes
What is a cell?
Simplest collection of matter that can live
What are some things all cells have and do?
- Plasma membrane
- Genetic material
- Ribosomes
- Distinct internal environment in the form of the cytoplasm
- Use and transform energy in the form of ATP
- Respond to external stimuli
- Replicate
- Relatively small
- Do the central dogma
What are 6 properties of cellular life?
- Have a catalytic metabolism and produce and use energy
- Have genetic metabolism and do DNA replication, transcription, and translation
- Growth
- Evolution
- Exchange genetic information
- Communicate through chemical signals
What are 2 things only some cells can do?
Differentiation and motility
What are 6 differences between prokaryotes and eukaryotes?
- Eukaryotes have membrane bound organelles and a nucleus
- Transcription and translation are coupled in prokaryotes, separate in eukaryotes
- Single circular chromosome in prokaryotes, multiple linear chromosomes in eukaryotes
- Plasmids in prokaryotes, none in eukaryotes
- More complex and varied metabolism in prokaryotes
- No cytoskeleton in prokaryotes
Why are prokaryotes a paraphyletic group?
Archaea are more closely related to eukaryotes than they are to bacteria
What traits do we know the last universal common ancestor had?
A cell membrane, DNA, ribosomes, and a metabolism. All cells today have them, ancestral traits
Why doesn’t grouping microbes by morphology work for determining phylogenetic relationships?
They all look the same under a microscope
What is a better way to determine phylogenetic relationships among microbes than morphology?
Genetic methods, using 16S rRNA sequences
What is 16S rRNA? Why is it good to use for determining phylogenetic relationships among microbes?
Is a piece of ribosomal rRNA. It’s good to use because everything has ribosomes and they are highly conserved. Ribosomes evolve very slowly because they’re so essential, so every sequence change in the ribosome is the result of species divergence
What is endosymbiosis?
A smaller bacterial cell got engulfed by a larger archaean cell and didn’t get destroyed. Instead it just kept doing its metabolism, kept living, and the two eventually become a single organism
What is the advantage for the smaller cell in endosymbiosis?
Protection from the environment