Given below are two statements: Statement I: Electrostatic precipitator is most widely used in thermal power plant. Statement II: Electrostatic precipitator in thermal power plant removes ionising radiations
In the light of the above statements, choose the most appropriate answer from the options given below:
The unique mammalian characteristics listed by NCERT include the presence of hairs, pinna (external ears), and mammary glands. These features are characteristic of mammals and help in identification. Among the options, only option 3 mentions hairs, pinna and mammary glands, making it the correct choice.
🧠 Did You Know?
Monotremes (egg-laying mammals) also have these features, but the combination of hairs, pinna, and mammary glands is broadly used to define mammals in NCERT texts.
💡 NCERT Memory Line:
Hairs, pinna and mammary glands are characteristic features of mammals.
Select the correct statements with reference to chordates.
A. Presence of a mid-dorsal, solid and double nerve cord.
B. Presence of closed circulatory system.
C. Presence of paired pharyngeal gills
D. Presence of dorsal heart
E. Triploblastic pseudocoelomate animals.
Choose the correct answer from the options given below:
Explanation:
Correct statements: B and C. Chordates have a closed circulatory system (blood confined to vessels). They possess pharyngeal gill slits (often paired) at some life stage. A is incorrect because the nerve cord in chordates is a dorsal hollow nerve cord, not a solid or double one. D is incorrect since the heart is typically ventral in chordates. E is incorrect because chordates are triploblastic and coelomate, not pseudocoelomate. Thus, B and C only are correct.
🧠 Did You Know?
NCERT emphasizes the five distinguishing features: notochord, dorsal hollow nerve cord, pharyngeal slits, post-anal tail, and segmented body plan with a closed circulatory system in chordates.
💡 NCERT Memory Line:
Chordates: triploblastic coelomates with a dorsal hollow nerve cord and closed circulatory system, plus pharyngeal gill slits in at least some life stage.
In cockroach, excretion is brought about by:
A.Phallic gland
B.Urecose gland
C.Ncphrocytes
D.Fat body
E.Collatcrial glands
Choose the correct answer from the options given below:
