In Pheretima, septa are absent between which segments?
3/4 and 9/10
4/5 and 8/9
5/6 and 7/8
7/8 and 6/7
During emergency which of the following hormone is secreted?
Aldosterone
Thyroxine
Adrenalin
Calcitonin
In cockroach, larval and nymphal characters are maintained by
ecdysone
salivary glands
parotid gland
juvenile hormone
D.
juvenile hormone
Juvenile hormone is produced by corpora allata in insects, it favors 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 prothoracic gland, in insects that triggers metamorphosis.
Salivary glands are the merocrine or epicrine type of gland. Their secretion diffuses out through the cell surface, causing no damage to the cell. In man, 3 pairs of salivary glands are present and in rabbit, they are 4 pairs. salivary glands are absent in frog.
Parotid glands are compound tubulo- acinar glands and are the type of salivary glands with a flask like secretory portion. Poison gland of a toad is modified parotid gland. In rabbit, parotid glands are the largest salivary glands present beneath the ears. Duct of parotid gland is known as Stenson's duct in man.
Which of the following is a transparent tissue?
Tendon
Fibrous cartilage
Hyaline cartilage
All of these
Which of the following cell type is capable of giving rise to other cell types in sponges?
Thesocytes
Pinacocytes
Cnidocytes
Archaeocytes
Animals having a built in thermostat to maintain constant body temperature are known as
biothermic
poikilothermic
oligothermic
homeothermic