STD 12 - 1. sexual reproduction in flowering plants — NEET STD 11 Science — Question

Humus is

Choose the correct one from given statements.
(i) Gametes can be flagellated and similar in size in Chlamydomonas.
(ii) Gametes can be flagellated, motile but dissimilar in size in Spirogyra.
(iii) In Chlamydomonas both isogamous and anisogamous reproduction occurs.
(iv) Fusion between one large, non-motile, static female gamete and a smaller, motile male gamete is termed oogamous.
(v) Oogamous reproduction occurs in Volvox. Fucus,

Catabolic and anabolic pathways are often coupled in cell, Why?

The filaments associated with cilia and flagella are constituted by

Fill in the blanks.
(i) 4-C compounds like A or B formed in mesophyll cell of C₄ plants are transported to the bundle sheath.
(ii) The bundle sheath cells are rich in an enzyme C but lacks D.
(iii) E pathway is common to C₃ and C₄ plants.
(iv) The active site of RuBisCO has both F and G_binding sites. It has greater affinity for H.
(v) PGA binds with O₂ to form one molecule of I and J in a pathway called photorespiration.
(vi) C₄ acid from the mesophyll is broken down in the bundle sheath cells to release K- this results in increasing the concentration of L.
(vii) M is the major limiting factor for photosynthesis.
(viii) Increase in concentration upto N % can cause an increase in CO₂ fixation rates; beyond this the level can become damaging over longer periods
(ix) C₄ plants show saturation at about O u1L^-1 while C₃ responds to increased CO₂ concentration and saturation is seen only beyond P u1L^-1.

In which approach threatened animals and plants taken out from their natural habitat and placed in special setting where they can be protected and given special care ?

Bt toxin protein crystals present in bacterium Bacillus thuringiensis, do not kill the bacteria themselves because

Heart wood or duramen is

In an ecosystem which of the following are important components