In cockroach, larval and nymphal characters are maintained by

Step-by-step solution

Juvenile hormone is produced by corpora allata in insects, it favours the development of juvenile characteristics. During larval life, this hormone predominates and each moult yields another larger juvenile and keeps the larva in immature condition or maintains juvenility. Ecdysone is a steroidal, moulting hormone of the prothoracic glands, named "ecdysone" in insects that triggers metamorphosis. Salivary glands are the merocrine or epicrine type of gland. Their secretion diffuses out through the cell surface, caus