What external changes are visible after the last moult of a cockroach nymph?
Mandibles become harder
Anal cerci develop
Both fore wings and hind wings develop
Labium develops
C.
Both fore wings and hind wings develop
In cockroach, development is paurometabolous. The nymph grows by moulting about 13 times to reach the adult form. The next to last nymphal stage has wing pads but only adult cockroaches have wings. Anal cerci are a pair of jointed filamentous structures in 10th segment of both sexes. Labium is a lover lip and a pair of mandibles are present in mouthparts of cockroach.
The crystal of lead zirconate is a key component of
sonography
electrocardiography
electroencephalography
magnetoencephalography
Assertion : Leaf butterfly and stick insect show mimicry to dodge their enemies.
Reason : Mimicry is a method to acquire body colour blending with the surroundings.
If both Assertion and Reason are true and the reason is the correct explanation of the assertion
If both Assertion and Reason are true but the reason is not the correct explanation of the assertion
If Assertion is true statement but Reason is false
If both Assertion and Reason are false statements
Lucocytes (WBCs) are considered as true cells because
they possess nucleus
they do not contain haemoglobin
they show great power of movement
they are responsible forphagocytic activity
The function of microvilli is :
cellular movement
specialized uptake of macro molecules
increase in surface area for absorption
extensive movement of substances over cell surface
Inner surface of the bronchi, bronchioles and fallopian tubes are lined by
cubical epithelium
columnar epithelium
squamous epithelium
ciliated epithelium
Which of the following tissues provide maximum mechanical support to plant organs?
Sclerenchyma
Collenchyma
Parenchyma
Aerenchyma
