Answer:
D
Explanation:
Methanogens are prokaryotes and therefore have prokaryotic cells. They are single-celled archaea. They are found in hypoxic conditions like the first stomach of ruminants where they digest molecules like cellulose and produce methane as a byproduct. The rest are composed of eukaryotic cells which are much larger than prokaryotic cells and their organelles are membrane-bound (unlike prokaryotes).
To perform this test to check if gold is real, make a light, tiny scratch on the item using a small nail file. Choose a spot that is not noticeable if possible. Use a dropper to apply a small drop of nitric acid to the scratch. If there is no reaction, then the piece is probably made from real gold.
Answer:
False
Explanation:
In eukaryotes apart from RNA polymerase, the transcription of genes requires many different proteins called transcription factors. These transcription factors are important to initiate and regulate transcription.
There are two types of transcription factors regulatory and basal transcription factors. Basal transcription factors regulate transcription by binding to a gene promoter and regulatory transcription factor regulates transcription by binding to some regulatory sequences for example enhancers and silencers.
Therefore only basal transcription factor binds to the promoter for regulating transcription. Therefore the statement is false.
Answer:
Legionella tends to form biofilms and infect other microbial cells as intracellular pathogens.
Explanation:
The Legionella genus of the bacteria is a group of gram-negative bacteria that can cause legionnaires disease.
The<em> Legionella pneumophila</em> is a species of this genus which can cause legion pneumonia. The bacteria lives in the freshwater and is resistant to chemical treatment like chlorine and the biocide treatment.
The reason for this resistance is since this species form a polysaccharide layer around the colony of the bacteria which is resistant to these treatments and also the bacteria prove parasitic to the protozoans which feed on these bacteria.
Thus, the selected option is the correct answer.