Answer:
Bacteriophages are attaching to bacterial cell wall and injecting genetic material.
Explanation:
Bacteriophage:
A bacteriophage (bacteria eater) is a type of virus that infects bacteria. Bacteriophages are composed of genetic material (DNA or RNA) enclosed in a protein shell or capsid.
Following are steps of bacteriophage infection:
- Bacteriophage attaches to cell surface receptors on the surface of the bacterium.
- Depending upon the type of phage, the bacteriophage either injects its DNA or RNA into the bacterium or enters as a whole. In this image, the bacteriophage T4 is represented which injects its genetic material into the host cell.
- The phage's genetic material hijacks the cellular machinery of the host and replicates itself within the host.
- After replication, the phages burst open the bacteria cell and are released. This is called the lytic cycle of bacteriophage infection.
- In another type of infection cycle, called the lysogenic cycle, the bacteriophage genome gets incorporated into the host genome, known as a prophage. This prophage lies dormant.
* The second step of the infection cycle is pictured here.
The answer is the letter a
Answer:
option A they have developed from the same organism
Explanation:
Organs of animals (belonging to different species) which have similar structure but different functions are homologous organs. Such organs have evolved from the same ancestors , however their function are different.
For example – wings of bats, limb of human etc.
Here in this case also the bone structures of human, cow, and horse are same but their functions are different, thus they are homologous organs and hence they have evolved from same ancestors.
The correct answer is option A
Answer:
Messenger RNA (mRNA) molecules carry the coding sequences for protein synthesis and are called transcripts; ribosomal RNA (rRNA) molecules form the core of a cell's ribosomes (the structures in which protein synthesis takes place); and transfer RNA (tRNA) molecules carry amino acids to the ribosomes during protein.
Explanation:
