I need help with plants and organisms:
1. In mycorrhiza which organisms benefits?
c. Both a and b
d. none of these
2. Wetlands such as estuaries swamps and marshes have the same productivity as tropical rain. Why does this make protection of wetlands so important?
3. A plant which does not receive enough water would
a. Increase turtle
b. Decrease photosynthesis
c. Both a and b
d. none of these
4. Imagine there was a campaign to wipe out bacteria. Why would this not be a good idea? Include the terms amnio acids, ammonia, nitrites and nitrates in the answer for the role of bacteria in the nitrogen cycle.
You have four questions here. Let's take them each in turn.
1. Mycorrhiza are bacteria that are associated with the roots of many plants. The technical term for the root system of a plant is the rhizopshere, hence the source of the name for the bacteria. Mycorrhiza form a symbiotic relationship with plants. The bacteria help the plant absorb water and also help it with the uptake of ionic minerals such as phosphates. In return, the plant can provide the bacteria with simple carbohydrates as a food source. Since both species benefit, the answer is C.
2. Protection of the wetlands is important for three major reasons. Marine wetlands can help protect fragile coastline that might otherwise suffer from erosion. The Mississippi River delta in Louisiana is a great example. Also, wetlands hold an enormous abundance of plant and animal life. Losing them would have serious negative effects on biodiversity. Finally, wetlands also serve as nature's water filtration system. The bacteria and microorganisms that flourish in the relatively still waters help to remove biomass and mineral nutrients in surface water before it drains into water systems like rivers, lakes, and oceans. In fact, recently in my area an effort was undertaken to re-establish damaged wetlands adjacent to farmland. The bacteria in the wetlands help to break down excess fertilizers and animal wastes before they can drain into a local river and affect a much larger water supply.
3. The basic chemical equation for photosynthesis is CO2 + H2O + sunlight --> sugars + O2. So water is required for photosynthesis. So if a plant did not receive enough water, it would decrease photosynthesis. I'll admit that I'm not entirely sure what you mean by "increase turtle", but it doesn't really seem to have any bearing here. That makes the correct answer B.
4. A campaign to wipe out all bacteria would not only be futile (microorganisms are the most abundant form of life on Earth), but also a massive natural catastrophe. There are many reasons for this, but you are clearly focusing on the effects on the nitrogen cycle in particular. Gaseous nitrogen (N2) is incredibly abundant and makes up about 80% of the planet's atmosphere. It is an incredibly inert chemical, however, and highly resistant to undergo chemical reactions to produce biologically useful chemicals that contain nitrogen. Nitrogen assimilation is the process by which gaseous nitrogen is converted into ammonia (NH3) through certain soil bacteria called diazotrophs (azo is Latin for nitrogen). The ammonia and ammonium ions (NH4+) are then further converted into other useful nitrogen containing ions like nitrites (NO2-) and nitrates (NO3-). These nitrogen containing ions are then assimilated by plants through their roots and are used to make amino acids and nucleic acids which are used by plants and animals through the food chain. When organisms die, other bacteria in the soil help convert the nitrogen containing chemical compounds back into gaseous nitrogen released into the atmosphere through a process called dentrification. So eliminating these useful bacteria would halt the nitrogen cycle and life on Earth as we know it would not be able to exist.