Which of the following is not an example of one of cannon’s postulates regarding the mechanisms that maintain physiological homeostasis? a. a neuron that fires action potentials at an intermediate rate at rest, but increases its rate when its stimulus changes@ no, this is an example of tonic levels of activity in a control system, which is one of cannon’s postulates. b. the sympathetic versus the parasympathetic nervous systems@ no, the sympathetic and parasympathetic divisions of the autonomic nervous system are a good example of antagonistic control, which is one of cannon’s postulates. c. epinephrine dilates some blood vessels and constricts others@ no, this is an example of the postulate that hormones can have different effects on different tissues. d. cervical stretch stimulates the release of oxytocin and uterine contractions@ yes, this is an example of a positive feedback loop, which does not maintain homeostasis, and therefore cannot be one of cannon’s postulates. e. neurons increase the heart rate in response to decreased blood pressure@ no, this is an example of control of homeostasis of blood pressure by neurons.

i have to report this, it doesn't relate to biology

halogen, any of the six nonmetallic elements that constitute group 17 (group viia) of the periodic table. the halogen elements are fluorine (f), chlorine (cl), bromine (br), iodine (i), astatine (at), and tennessine (ts).

i'm sorry, but can you list the answers? i cannot with something i don't know the answers to

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chris

transcription is a process in which information is rewritten. it is something our cells must do, in a more specialized and narrowly defined way. in biology, transcription is the process of copying out the dna sequence of a gene in the similar alphabet of rna. it needs to happen in the nucleus because that's where the dna is. dna is always inside the nucleus unless the cell is dividing.

transcription is the first step in gene expression, which involves copying a gene's dna sequence to make an rna molecule. transcription is performed by rna polymerases. it has three stages: initiation, elongation, and termination. rna molecules must be processed after transcription in eukaryotes.

explanation:

long version:

the protein synthesis consists two processes which are, transcription and translation. transcription takes place in the nucleus. it uses dna as a template to make an rna molecule. rna then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. transcription is the first part of the central dogma of molecular biology: dna → rna. it is the transfer of genetic instructions in dna to messenger rna (mrna). during transcription, a strand of mrna is made that is complementary to a strand of dna.  

these three stages are:

  initiation: in which   is the beginning of transcription.occuring when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

    elongation: in which is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

    termination: in which is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.