Which of the following cell type is capable of giving rise to other cell types in sponges?
Thesocytes
Pinacocytes
Cnidocytes
Archaeocytes
D.
Archaeocytes
Archaeocytes are the totipotent cells, which provide great regenerating power to sponges. Sex cells (sperm and ova arise from undifferentiated archaeocytes).
Thesocytes are the amoebocytes with reserve food granules.
Pinacocytes are the polygonal flat cells present as outer layer of cells, called pinacoderm lining the spongocoel or body cavity in Leucosolenia.
Cnidocytes occur in entire epidermis except that of basal disc and are found only in cnidarians. These are spherical or oval cells.
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
Animals having a built in thermostat to maintain constant body temperature are known as
biothermic
poikilothermic
oligothermic
homeothermic
In cockroach, larval and nymphal characters are maintained by
ecdysone
salivary glands
parotid gland
juvenile hormone
Which of the following is a transparent tissue?
Tendon
Fibrous cartilage
Hyaline cartilage
All of these
