Pollen tube growth is one of the most fascinating—and essential—phenomena in the life cycle of flowering plants. After a compatible interaction between pollen grains and the stigma surface, the pollen germinates and forms the pollen tube, which grows through the stigma, style, and transmitting tract to deliver the sperm cells to the ovule."
2) Although pollens of many species germinate in simple aqueous media, stigmas do not provide satisfactory sites for the germination of most foreign pollen... Stigmas not only provide the proper conditions for the germination of pollen from their particular species, they actively inhibit the germination of pollen of many unrelated species.
Answer:
Photosynthesis is the answer
Ans is option C. They both need an energy source in order to survive.
Energy is an absolute necessity to survive on this earth. All living organisms need energy be it anaerobic or photosynthetic. Photosynthetic organisms can make their own food in the presence of sunlight by photosynthesis and harness energy from it. Anaerobic organisms can also make their own food in the absence of sunlight with the help of inorganic molecules like hydrogen sulfide (H2S), ammonia (NH3), sulphur (S) etc.
Its just that anaerobic organism's way of harnessing energy is different from those of aerobes/photosynthetic organisms but they need energy source for sure.
The right answer is opposite.
In the air, the biomass of primary producers is often much higher than the biomass of consumers, especially in forests where a large part of the biomass is wood. In aquatic environments and especially oceanic, the biomass of primary producers (phytoplankton) is generally lower than that of consumers but this biomass is rapidly renewed.