Three Domains of Life Flashcards
Which domain(s) have a nuclear membrane?
Eukarya
Which domain(s) have membrane-bound organelles?
Common in eukarya, rare in bacteria and archaea
Which domains have similar plasma membranes?
Bacteria and eukarya
Which domain(s) have cell walls in most species?
Bacteria and archaea
How many RNA polymerase does each domain have?
Bacteria and archaea : 1
Eukarya: 3
Which domain(s) have histones?
Archaea and eukarya; bacteria has histone-like protein
What evidence is there of endosymbiosis theory?
Mitochondria and chloroplasts have a double membrane, own DNA and can replicate on their own
What is the bacteria and eukarya plasma membrane composed of?
Glycerol 3-phosphate, ester linkage, fatty acid chain
What is the archaea plasma membrane composed of?
Glycerol 1-phosphate, ether linkage, phytanyl
What about the archaea plasma membrane allows it to maintain stability in high temperatures?
The phytanyl tail can link with another phytanyl tail, forming a strong covalent bond
What is the archaea cell wall composed of?
B-1,4 linkage, D - amino acids
What is the bacterial cell wall composed of?
B-1,3 linkage, L - amino acids
Which is more complex, the bacterial or archaeal flagella?
Bacterial
How many protein types does bacterial flagella have?
1
How many protein types does archaeal bacterial have?
More than 1
Thermophile
Lives in temps above 55 C
Hyperthermophile
Lives in temps above 80 C
Acidophile
Lives in acidic conditions
Barophile
Lives in high pressure conditions
Which is compositionally different about thermophiles that allows they to live at high temperatures?
Different amino acid composition; more arginine and tyrosine
- Increase side chain interactions between neighbouring amino acids
- creates more stable protein folds
Why don’t halophiles dehydrate?
High K+ accumulate inside of cell, balancing Na+ outside of cell
How do halophiles prevent DNA damage caused by K+?
High percentage of cytosine and guanine, the three hydrogen bonds keep DNA stable
How to fungi feed?
Heterotrophy
How do most protozoa feed?
Heterotrophy
What is the difference between gram positive and gram negative bacteria?
Gram position - thick layer of peptidoglycan
Gram negative - thin layer of peptidoglycan and outer membrane composed of lipopolysaccharides
Which are the only gram positive bacteria?
Firmicutes and actinobacteria
Generalized transduction
When a random piece of bacterial chromosomal DNA is transferred by the phage during the lytic cycle
Specialized transduction
At the end of the lysogenic cycle, when the prophage is excised, and the bacteriophage enters the lytic cycle
