Answer:
The correct answer would be d. thymus.
The thymus is a specialized lymphoid organ of an immune system.
It serves as the site for training and maturation of T-lymphocytes or T cells.
It is composed two identical lobes each containing outer region termed as cortex and inner region termed as medulla.
T-cells are first trained and selected in the cortex region via positive selection. In this, T cells which are able to bind to foreign antigens are selected and rest are degraded.
The selected T cells then move in the medulla region where they are selected by negative selection. In this, the T cells which binds to self-antigens are degraded and rest survive to become functional T cells.
The brain is the nucleus it controls everything such as the nucleus controls everything in a plant cell and animal cell
All organic compounds contain covently bonded carbon. They are made up of the monomer Amino Acids. When amino acids join to form a protein. Which is then translated. This is an organelle in the nucleus that creates ribosomes!
They then examined the infected cells and found that they contained labeled DNA, Since the phage DNA entered the infected cell, which demonstrated that it makes sense that DNA is the phage's genetic material. A bacteriophage or a phage is a virus that infects and replicates within Bacteria and Archaea. Phages replicate within the bacterium following the injection of their genome into its cytoplasm.
Answer:
soil forms fastest in dry ,cool habitats
