In stratosphere, which of the following elements acts as a catalyst in degradation of ozone and release of molecular oxygen?
Carbon
Cl
Oxygen
Fe
B.
Cl
UV rays act on CFCs, releasing Cl atoms, chlorine reacts with ozone in the sequential method converting into oxygen Carbon, oxygen and Fe are not related to ozone layer depletion.
Niche is
all the biological factors in the organism's environment
the physical space where an organism lives
the functional role played by the organism where it lives
the range of temperature that the organism needs to live
What type of ecological pyramid would be obtained with the following data?
Secondary consumer : 120 g
Primary consumer : 60 g
Primary producer : 10 g
Inverted pyramid of biomass
Pyramid of energy
Upright pyramid of biomass
Upright pyramid of numbers
Natality refers to
Death rate
Birth Rate
Number of individuals entering a habitat
Number of individuals leaving the habitat
Match the items given in Column I with those in Column II and select the correct option given below:
| Column I | Column II | ||
| a | Herbarium | i | It is a place having a collection of preserved plants and animals |
| b | Key | ii | A list that enumerates methodically all the species found in an area with brief description aiding identification |
| c | Museum | iii | Is a place where dried and pressed plant specimens mounted on sheets are kept |
| d | Catalogue | iv | A booklet containing a list of characters and their alternates which are helpful in identification of various taxa. |
| a | b | c | d |
| (i) | (iv) | (iii) | (ii) |
| a | b | c | d |
| (iii) | (ii) | (i) | (iv) |
| a | b | c | d |
| (iii) | (iv) | (i) | (ii) |
| a | b | c | d |
| (ii) | (iv) | (iii) | (i) |
Which of the following statements is correct?
Ovules are not enclosed by ovary wall in gymnosperms
Selaginella is heterosporous, while Salvinia is homosporous
Stems are usually unbranched in both Cycas and Cedrus
Horsetails are gymnosperms
