The stomach <span>walls have a lining that contains epithelial cells that have a protective layer of mucus and bicarbonate. The mucous is pretty much the same stuff which lines our throat and nose.</span>
Answer:
Explanation:
The O-F glucose test (oxidative-fermentation) is used to determine whether an organism is performs oxidative or fermentative metabolism.
Oxidative metabolism (i.e respiration) takes place in the presence of oxygen while fermentative takes place in the absence of oxygen.
Facultative anaerobes can carry out both fermentation and respiration.
The O-F medium has glucose, peptones and a pH indicator. When the pH of the medium is acidic, that is glucose has been broken down, the medium turns yellow. When it is basic, it turns blue implying that peptone and not glucose had been broken down.
The sealed tube is overlaid with oil so as to prevent oxygen from getting in, making it anaerobic.
The unsealed tube allows oxygen.
Enterics would be yellow is both tubes because they are facultative anaerobes and can grow in the presence or absence of oxygen, hence they carry out both respiration and fermentation.
Answer:
F oxygen
Explanation:
we need oxygen for respiration and hydration
Answer:
A) many noncoding stretches of nucleotides are present in mRNA.
Explanation:
A transcription unit in eukaryotes includes the region that code for mRNA extending from the 5' cap site to the 3' poly-A site. It also includes the controlling regions. The mRNA formed by transcription also has some non-coding intervening sequences. These are called introns. Introns are removed from the primary transcripts by the process of splicing that occurs after transcription.
Therefore, a transcription unit that is 8,000 nucleotides long may use only 1,200 nucleotides to code for a protein having 400 amino acids since the rest of the nucleotides are part of introns and are removed from mRNA after transcription.
