Myelin sheath is produced by
Schwann Cells and Oligodendrocytes
Astrocytes and Schwann Cells
Oligodendrocytes and Osteoclasts
Oligodendrocytes and Osteoclasts
Which one of the following in birds, indicates, their reptilian ancestry?
Scales on their hindlimbs
Four-chambered heart
Two special chambers crop and gizzard in their digestive tract
Eggs with a calcareous shell
Six highly chitinous plate-like teeth are found in ……. of cockroach
Mandible
Gizzard
Mexilla
Rectum
Organisms who are able to freely interbreed producing fertile off-springs and having a similar blueprint for making these organisms are referred to as
Species
Tribe
Genus
Sub-genus
The stratified epithelium is found in
Seminiferous tubule
Fallopian tube
Nasal cavity
Kidney tubules
The blood of cockroach contains no respiratory pigment. It means that
respiration is anaerobic
cockroach does not respire
oxygen goes directly into tissues by diffusion
oxygen goes into tissue by intracellular capillary system
C.
oxygen goes directly into tissues by diffusion
Class- Insecta of Phylum- Arthropoda, is characterised by the presence of three pairs of legs and absence of respiratory pigments in blood, eg, cockroach, mosquito.
In cockroach, respiration is aerobic and oxygen goes into tissues by diffusion through the trachea.
Which is common between earthworm, leech and centipede?
They have Malphigian tubules
They are hermaphrodite
They have ventral nerve cord
None of the above