<span>Mammals first appeared during the Cenozoic Era. The statement is true.</span>
The Prader-Willi syndrome (PWS) is due to the lack of expression of paternal genes of the 15q11-q13 region. It usually occurs sporadically, although some family cases have been described (<1%). Approximately 70% of cases are produced by deletions of paternal origin in the 15q11-q13 region. 28% of cases are due to maternal uniparental disomy and less than 2% are caused by imprinting alterations. A geneticist studying prader-willi syndrome should focus on chromosome 15, its structure or changes in the number, these anomalies are also related to other syndromes such as: Bloom Syndrome, Breast cancer, Isovaleric acidity among others.
1. The given blank can be filled with vestibular nerve.
The vestibular nerve in humans conducts sensory information conducted by the vestibular hair cells situated in the utricle and the saccule, that is, the two otolith organs, and the three semicircular canals through the vestibular ganglion. It relays information to the brain about balance.
2. The correct answer is option b, that is, the vestibular sense may be capable of sensory adaptation.
The awareness of the movement and the balance of the body are controlled by the vestibular system. The vestibular senses, that is, the feelings of gravitation and movement and rotation of the body originate in the inner ear. The sense organs are the cells of the hair, which transmit signals over the auditory nerve.
