quiz 7- week 9 Flashcards
What is horizontal gene transfer in microbes?
It is the transfer of genes between organisms in a manner other than traditional reproduction, contributing to genetic diversity
Describe endosymbiosis.
A symbiotic relationship where one organism lives inside another, thought to be key in the evolution of organelles like mitochondria and chloroplasts
Name two types of Gram-positive bacteria.
Staphylococcus (Staphs) and Streptococcus (Streps)
What are some examples of Gram-negative bacteria?
E. coli, Salmonella, Pseudomonas, and Proteus
What is the significance of cyanobacteria?
They generate the majority of Earth’s oxygen and vary in shape and physiology while being photosynthetic
Why don’t cyanobacteria test as Gram-positive despite having thick peptidoglycan walls?
They do not allow crystal violet to penetrate
What is a unique feature of archaeal chromosomes?
They are circular and have no membrane-bound organelles, similar to bacteria
How do archaea resemble eukaryotes in protein synthesis?
Archaea use methionine as the first amino acid and have a histone-like structure for DNA compaction
What adaptations do hyperthermophiles have for extreme heat?
They use positive DNA coils to add stability and prevent DNA “melting” in high temperatures
Describe the environment that sulfur thermophiles inhabit.
They live in hot springs with reduced minerals, low oxygen, high acidity, and steep temperature gradients
What are Thaumarchaeotes, and what is their role?
They are ammonia-oxidizing archaea, converting ammonia to nitrite/nitrate as part of their metabolism
What superphylum includes both fungi and animals?
Opisthokonta
What are slime molds, and when do they form?
Slime molds are formed by amoebas in response to stressful conditions
Describe the feeding mechanism of fungi.
Fungi release enzymes into the environment to digest food externally and then absorb the nutrients
What are the two forms of reproduction in yeast?
Yeasts reproduce asexually through budding or binary fission
