Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R: Assertion A: The first stage of gametophyte in the life cycle of moss is protonema stage. Reason R: Protonema develops directly from spores produced
in capsule.
In the light of the above statements, choose the most appropriate answer from the options given below:
Explanation:Assertion A is correct: in moss, the first stage of the gametophyte is the protonema. Reason R is also correct: protonema develops directly from the spores released from the capsule. Since protonema arises from germinating spores and then develops into the leafy gametophyte, R explains how the protonema (the first gametophyte stage) originates. Therefore, option 2 is correct. ? Did You Know?In mosses, the gametophyte is dominant and photosynthetic, while the sporophyte is dependent on the gametophyte for nutrition. ? NCERT Memory Line:Germination of a spore produces the protonema, from which the juvenile gametophyte (leafy moss) develops.
Question 2 of 15
🟢 NEET 2023📘 CLASS XI
Identify the pair of heterosporous pteridophytes among the following:
Explanation will be generated when opened.
Question 3 of 15
🟢 NEET 2023📘 CLASS XI
Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R:
Assertion A: In gymnosperms the pollen grains are released from the microsporangium and carried by air currents.
Reason R: Air currents carry the pollen grains to the mouth of the archegonia where the male gametes are discharged and pollen tube is not formed.
In the light of the above statements, choose the correct answer from the options given below:
Explanation will be generated when opened.
Question 4 of 15
🟢 NEET 2022📘 CLASS XI
Which of the following is incorrectly matched?
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Question 5 of 15
🟢 NEET 2022📘 CLASS XI
Hydrocolloid carrageen is obtained from:
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Question 6 of 15
🟢 NEET 2022📘 CLASS XI
Match the plant with the kind of life cycle it exhibits:
List-I
List-II
(A)Spirogyra
(I)Dominant diploid sporophyte vascular plant, with highly reduced male or female gametophyte
(B)Fern
(II)Dominant haploid free-living gametophyte
(C)Funaria
(III)Dominant diploid sporophyte alternating with reduced
gametophyte called prothallus
(D)Cycas
(IV)Dominant haploid leafy gametophyte alternating with
partially dependent multicellular sporophyte
Choose the correct answer from the options given below:
Explanation will be generated when opened.
Question 7 of 15
🟢 NEET 2021📘 CLASS XI
Which of the following algae produce Carrageen?
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Question 8 of 15
🟢 NEET 2021📘 CLASS XI
Genera like Selaginella and Salvinia produce two
kinds of spores. Such plants are known as:
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Question 9 of 15
🟢 NEET 2021📘 CLASS XI
Which of the following algae contains mannitol as
reserve food material?
