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
Answer:
The correct answer is (b)-False
Explanation:
Bacteria do not undergo meiosis or mitosis to reproduce and increase its genetic recombination. To increase their genetic recombination bacteria take the help of horizontal gene transfer through which it gets the genetic material of another bacteria. This new gene helps bacteria to survive in the challenging environment.
Bacteria divide through binary fission in which one cell of bacteria divides into two equal daughter cell each having its genetic material because genetic material of parent cell segregate equally into both the cell.
Therefore bacteria do not undergo meiosis or mitosis.
The correct answer is Karl will get sick and Jose will not this time, but neither will get this influenza again since they both will have acquired active immunity to it.
In the case of Jose artificially active immunity has been induced due to vaccination. A vaccine instigates a primary response against the antigen without resulting in any signs of the disease. On the other hand, Karl will acquire active immunity naturally in future, as when an individual get exposed to a live pathogen, he or she develops the disease, and turns immune as an outcome of the primary immune response.
A person can be anxious when making an important decision when faced with a problem at work. Types of disorders are;
1. Generalized anxiety disorder symptoms include
a) irritability
b) muscle tension
c)Being easily fatigued.
2. Panic disorder symptoms include
a)feeling of being out of control during a panic attack.
b)Repeated and sudden attack of intense fear.
3. Social anxiety symptoms
a)Having a very hard time making friends.
b)feelings of self-conscious in front of other people
c)Staying away from where other people are.
Answer: a mutagens d carcinogens b point mutation c frameshift e missense f nonsense
Explanation: Hope that helps!
