Answer:
False.
Explanation:
The membrane potential may be defined as the difference in the electric potential of the cell between the outside and inside environment. The unequal distribution of ions is responsible for membrane potential.
Different cells that carries the resting membrane potential are nerve cell, muscles cell and many more. The resting membrane potential of nerve cell is -70mV.
Thus, the correct answer is option (b).
Answer:
The two important conditions that must be met before gram staining are-
1. The age of the culture should not exceed 24 hours.
2. Over heating, decolonization should be avoided.
Explanation:
Gram staining is a technique developed to distinguish the bacteria on the basis of the composition of the cell wall around the bacteria.
The gram stain is a sensitive technique so must be performed carefully. The precautions should be taken to avoid any error while gram staining that is-
1. Age of the culture- The culture should be freshly prepared just 18-24 hours before the experiment as above 24 hours bacteria lose their ability to retain the color so one would not be able to differentiate between the cultures.
2. While performing the experiment one should avoid overheating and decolorization with ethanol as both the factors lead to the loss of crystal violet stain from the cell and they take pinkish color after safranin staying.
Transcription factors are necessary for an initiation of transcription at a regulated gene but not sufficient.
Transcription is the first step of gene expression in which DNA molecule is copied (transcribed) into RNA (mRNA) by RNA polymerase. The process of transcription is divided into three phases:
1. Initiation
• RNA polymerase with transcriptional factors bind to gene promoter Transcription factors can enhance the interaction between RNA polymerase and a DNA sequence- promoter, encouraging the expression of the gene. Such transcription factors are called activators. Otherwise, when the gene expression is inhibited, factors are called repressors and they bind to sequence –operator.
• RNA polymerase unwinds DNA double helix (transcription bubble is formed)
2. Elongation
• RNA polymerases adds nucleotides complementary to DNA
3. Termination
• RNA polymerase gets to stop codon (transcribes a sequence of DNA known as a terminator)
• Formed complementary RNA strand is released from DNA-RNA complex
Yes, it is a weak acid called the citric acid
