The answer is because they are not necessary for the plant to reproduce
Forest biome: It gives us medicinal plants, woods for commercial purpose. Forests provides us rubber and fibers that is very important for the industries for making various products. They also contribute to perform ecological functions such as carbon storage, nutrient cycling, water and air purification. It also provides habitat to the wildlife.
Freshwater biome: We use fresh water for drinking water, irrigation, sanitation systems, and in industrial factories. Water used from groundwater, rivers and lakes is regained by rain and snowfall.
Marine biome: It serves huge amount of oxygen into the environment and absorbs the atmospheric carbon dioxide.
As a result of the activity of human there is a significant decrease in the number of trees. The products now used are synthetically made which were made up of natural fibers previously. The water source such as rivers, lakes, and ponds are polluted due to which many water borne diseases are increasing day by day. The accumulation of waste which are found in marine biome are reducing the number of flora present inside marine ecosystem.
Answer: A scenario often presented to introductory physics classes is that of a "gravity tunnel" — a tube drilled from one side of the Earth to the other through the planet's center. The answer taught for nearly a half-century for how long a fall through such a hole would take was about 42 minutes and 12 seconds.
Explanation: However, solar and lunar gravity, which also perturb orbiting satellites, would eventually pull you into the tunnel wall anyway [source: Darling ]. Strike a chord: Fun fact: A straight line from any point to any other point through the planet would take the same amount of time to fall through like a tunnel through Earth's center.