If we take a look at the phylogenetic tree of bears presented in the picture above, we can see that the branch number one is the common ancestor to all living bear species, which means that the whole group has a uniform origin. and the
phylogenetic tree has a root. Therefore, the group is monophyletic, not <span>polyphyletic ( meaning that the whole group has the same origin) and not paraphyletic ( there is no group that has been excluded from the tree).</span>
It is the total mass of organisms in the given area
Answer:
Hormones act as first messenger but not as second messengers.
Explanation:
Second messenger act as signaling molecule which are secreted in response to various biological signals generated by first messenger such as hormones,neurotransmitters etc.Second messengers include various bioactive molecules such as cyclic AMP(cAMP),cyclic GMP(cGMP),inositol triphosphate(IP3),diacylglycerol(DAG),calcium ions(Ca2+) etc.
Hormones are extracellular signaling molecules whereas second messengers are intracellular signaling molecules.
Explanation:
Phytoanticipins are defined as defense compounds which are constitutively present, i.e., regardless of the presence of pests or diseases.