Which one of the followings in birds, indicates their reptilian ancestry?
Scales on their hind limbs
Four chambered heart
Two special chambers crop and gizzard in their digestive tract
The rupture and fractionation do not usually occur in the water column in vessel/tracheids during the ascent of sap because of
lignified thick walls
cohesion and adhesion
weak gravitational pull
weak gravitational pull
The blood calcium level is lowered by the deficiency of
parathormone
thyroxine
calcitonin
calcitonin
Dry indehiscent single-seeded fruit formed from bicarpellary syncarpous inferior ovary is
Caryopsis
cypsela
Adiantum
Adiantum
The fleshy receptacle of syconus of fig encloses a number of
achenes
samaras
berries
berries
Which one of the following is linked to the discovery of Bordeaux mixture as a popular fungicide?
Bacterial leaf blight of rice
Downy mildew of grapes
Loose smut of wheat
Loose smut of wheat
The length of different internodes in a culm of sugarcane is variable because of
shoot apical meristem
position of axillary buds
size of leaf lamina at the node below each internode
size of leaf lamina at the node below each internode
Which one of the following is the correct difference between rod cells and cone cells of our retina?
Features |
Rod cells |
Cone cells |
Visual acuity |
High |
Low |
Features |
Rod cells |
Cone cells |
Visual Pigment contained |
Iodeosin |
Rhodopsin |
Features |
Rod cells |
Cone cells |
Overall function |
Vision in poor light |
Colour vision and detailed vision in bright light |
Features |
Rod cells |
Cone cells |
Overall function |
Vision in poor light |
Colour vision and detailed vision in bright light |
C.
Features |
Rod cells |
Cone cells |
Overall function |
Vision in poor light |
Colour vision and detailed vision in bright light |
The retina is the neural and sensory layer of the eyeball. A small, oval yellowish area of the retina lying exactly opposite the centre of the cornea is named the macula lutea or yellow spot, which has at its middle a shallow depression the fovea centrails. The foveacentrails has cone cells only. It is devoid or rods and blood vessels. The rods contain the rhodopsin (visual purple) pigment and enable to animals to see in darkness. Therefore. present in large number in nocturanal animals.The cones contain the iodopsin (visual violet) pigment and chiefly concerned with distinction in colour and light vision during daytime.