Chapter 27 Flashcards
(26 cards)
Are bacteria prokaryotic or eukaryotic?
Eukaryotic
How do bacteria reproduce and evolve?
Exponentially, evolve very quickly
What are extremophiles?
Organisms that can live in extreme environments
Most life on earth is ________
Microbial
What are the 3 domains? Which is visible?
Eukarya (Visisble), bacteria, archaea
What were the dirst organisms like? When did they live?
3.5 billion years ago, projaryotic, mostly unicellular. Tons of natural selection
Do prokaryotes generally have cell walls?
Yes
What purpose do cell walls serve in prokaryotes?
Environmental protection, prevents bursting in hypotonic environment (water coming in), maintaining cell shape
What are plant cell walls made of?
Cellulose
What are fungi cell walls made of?
Chitin
What are bacterial cell walls made of?
Peptidoglycan
What defines gram positive bacteria?
Thick peptidoglycan wall
What defines gram negative bacteria?
Outer membrane, thin inner layer of peptidoglycan,
What adaptations do bacteria have? What do these do?
Capsules, slime layers, endospores (survive when bacteria can’t, repopulate). All enclose and protect from environment
What do fimbriae, pili, and flagella all do?
Stick to stuff, control movement (Towards good stuff, away from the bad)
What are fimbriae?
Appendages that allow bacteria to stick to things
What are pili?
Hair like structures that stick to things and help bacteria move
What are flagella?
A taillike appendage that helps with movement
How many chromosomes do bacteria have? What shape are they?
1, circular
How do bacteria reproduce?
Binary fission
What is genetic recombination?
Combining DNA from bacterial cells
What is horizontal gene transfer?
Transferring DNA across different species
What is transformatoin?
Uptake of foreign DNA that changes cells
What is transduction?
Transfer of DNA by phage
