STD 11 - 9. Biomolecules — NEET STD 11 Science — Question

Choose correct one.

What does the filiform apparatus do at the entrance into ovule?

Which one of the following statements are correct ?
(i) Chromatids start moving towards opposite poles in anaphase.
(ii) Crossing over occurs between non-sister chromatids of homologous chromosomes.
(iii) Crossing over occurs in tetrad stage which occurs in pachytene of prophase I of meiosis I.
(iv) Chromosomes move to the spindle equator and get aligned along equatorial plate in metaphase.
(v) Crossing over is the reciprocal transfer of genes between the non-homologous chromosomes
(vi) M phase represents the phase when actual cell division occurs and I phase represents the phase between two successive M phase.
(vii) In the 24 hours, average duration of cell cycle of a human cell, cell division proper lasts for only about an hour.
(viii) M phase constitutes more than 95% of the duration of cell cycle.
Choose the correct option given below :-

Most primitive members of the plant kingdom are

Reserve food material of algae is

The thalloid body of a slime mould (Myxomycetes) is known as

Which of the following characters for algae are incorrect from given characters ?
(i) At least a half of the total carbon dioxide fixation on earth is carried out by algae through photosynthesis.
(ii) Being photosynthetic they decrease the level of dissolved oxygen in their immediate environment.
(iii) Many species of Porphyra, Laminaria and Sargassum are used by space travellers as food.
(iv) Certain freshwater brown and red algae produce large amounts of hydrocolloids,
(v) Agar obtained from Gelidium and Gracilaria.