The answer is D.
A retrovirus is any of a group of viruses that characteristically carry their genetic information in form of RNA. These viruses have an enzyme called reverse transcriptase from which they derive their name because they follow the first step of the central dogma backward thus "retro" which means backward.
Reverse transcriptase makes DNA from RNA template thus reversing the usual pattern of transcribing RNA using DNA as the template.
The central dogma of molecular genetics summarizes steps of protein synthesis as DNA → RNA → protein. But retroviruses have modified the process to be RNA → DNA → RNA → protein.
Answer:
The correct answer will be option-B.
Explanation:
A neurotransmitter is a chemical messenger used by the nerve cells to transmit the signals from one neuron to another neuron and muscle cell at the synaptic cleft. The common neurotransmitter is acetylcholine, dopamine, serotonin and others.
The neurotransmitter can be excitatory that is causing the generation of the action potential in the neurons or inhibitory that is prevent the generation of neuron in neuron cell. This depends on the receptors to it binds.
The neurotransmitters can be degraded or can be taken back after the work is completed. thus, Option-B is the correct answer.
Some algae have chloroplasts and chlorophyll and obtain their energy through photosynthesis while some algae like euglena are both heterotrophic (decompose dead organic matter) and autotrophic (use photosynthesis) and can also obtain energy likewise.
Answer:
Promoter.
Explanation:
It is promoter because Promoter is a DNA sequence where's the gene transcription begins. It is the
DNA sequence which RNA polymerase binds or join to
so as to begin transcriptionn of a gene . It is a region where the regulatory elements i.e protein will bind to and the Promoter sequences are found directly upstream or at the end of 5' of the transcription initiation site. This can also encode RNA such as mRNA, trans and so on.