Which of these modes of transmission require a bodily opening either natural or artificial?

Vectors-These are diseases transmission which involves the piercing of the skin-vectors penetration  e.g by mosquito. ticks.

Air borne which involves entry through the nasal passages, mouth, eyes to reach the body  the respiratory tracts and the blood.

Blood borne diseases are  transmitted from e.g piercing of the skin by  contaminated objects needles, broken glass. If there is an opening in the skin these transmission is also possible.

Sexual can be transmitted through open sores at the genitals.or  use of  contaminated needle by infected subject. Sores in the mouth during kissing may be another route

food borne or water borne needs to enter through natural opening of the mouth to reach the body fluids and the blood through the GIT.

Contact diseases does not necessarily need a direct opening for transmission . rather there should be a direct contact between the infected individual and the other. Sometimes a direct contact between the two is not need. e.g common cold, chicken pox , influenza , etc.  

Explanation:

[content deleted] - user123802726recklesschicken

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.