The least common but most deadly type of skin cancer is

A. rRNA is always attached to the rough ER:Ribosomal RNA is a structural component of ribosomes, which may be free in the cytoplasm or attached to the rough ER. It is not always bound to the rough ER, making this statement inaccurate.

B. If the base sequence of DNA is ATTGCA, the messenger RNA template will be UCCAGU:The correct complementary mRNA sequence would be UAACGU, where adenine pairs with uracil, thymine with adenine, and cytosine with guanine. The sequence given in the option does not follow base-pairing rules.

C. Messenger RNA, transfer RNA, and ribosomal RNA play a role in protein synthesis:All three RNA types are essential for protein synthesis. mRNA carries genetic information from DNA, tRNA delivers amino acids to the ribosome, and rRNA provides structural support and enzymatic activity within ribosomes.

D. There is exactly one specific type of mRNA for each amino acid:mRNA molecules carry codons that specify amino acids, but there is no one-to-one relationship between mRNA and amino acids. Multiple codons may code for the same amino acid due to the redundancy of the genetic code.

A. Melanocytes:Melanocytes are specialized cells that produce melanin to protect against UV radiation. They do not function as sensory receptors and are not involved in touch sensation.

B. Keratinocytes:Keratinocytes form the majority of the epidermis and provide a protective barrier. While they interact with other skin cells, they do not detect sensory stimuli.

C. Adipocytes:Adipocytes are fat cells located in the subcutaneous layer. They serve as energy storage and insulation but are not involved in sensing touch.

D. Dendritic cells:Dendritic cells are immune cells in the skin that detect pathogens and present antigens. They play a role in immune defense rather than tactile sensation.

E. Tactile cells:Tactile cells, also known as Merkel cells, are specialized mechanoreceptors located in the basal layer of the epidermis. They detect light touch and pressure, transmitting sensory information to sensory neurons.