Answer:
The node therefore represents the end of the ancestral taxon and the stems , the species that split from the ancestor. The two taxa that split from the node are called sister taxa.
Explanation:
The answer is b the protists
Answer:
secrete a cytokine that triggers apoptosis
Explanation:
Cytotoxic T cells secrete granzymes and perforins when targeting cells. Additionally they secrete cytokines such as IFN-, TNF-α and TNF-β that act to activate macrophages and help kill infected cells.
The nitrogen cycle. Animal and plant waste decomposes and adds nitrogen to the soil, which bacteria convert into a form that plants use to grow. Animals eat the plants, which completes the cycle.
