When a muscle receives nerve signal contracts and pulls on a tendon.
Operons are the functional units of transcription and genetic regulation. These are found in bacteria and their viruses where genes coding for functionally related proteins are grouped along the DNA.
The two types of operons are- inducible and repressible.
They regulate the genes as in negative inducible operons, a regulatory repressor protein is bound to the operator. It prevents the transcription of the genes on the operon. If positive inducer is present, it binds to the repressor and changes its conformation so it is unable to bind to the operator.
The epithelial cell will have 38 chromosomes
A 2n or 2(19) = 38 chromosomes. This is because n is called haploid number of chromosomes; the number of chromosomes present in the gametes. Epithelial cells like other body cells divides through the process of mitosis; therefore; the parent cells yields daughter cells with the same number of chromosomes (diploid). The other haploid (n) number is present in the gametes which divides by the process of meiosis.