"Nearly all of the energy<span> that drives ecosystems ultimately comes from the sun. </span>Solar energy<span>, which is an abiotic factor, by the way, enters the ecosystem through the process of </span>photosynthesis<span>. You can learn more than you want to know about this process in the unit on photosynthesis. Or, you could just chat with your local </span>botanist<span>. Everyone has one, right? The organisms in an ecosystem that capture the sun’s </span>electromagnetic energy<span> and convert it into </span>chemical energy<span> are called </span>producers<span>. Not to be confused with these </span>Producers.
<span>The name is appropriate because </span>producers<span> make the carbon-based molecules, usually carbohydrates, that the rest of the organisms in the ecosystem, including you, consume. Producers include all of the green</span>plants<span> and some </span><span>bacteria </span><span>and </span>algae<span>. Every living thing on Earth literally owes its life to the producers. The next time you see a plant, it wouldn’t be a bad idea for you to thank it for its services...which, as you will learn in other units, go way beyond just supplying you with food. </span>
After a producer has captured the sun’s energy and used it to grow yummy plant parts, other organisms come along and greedily gobble it up.These primary consumers, as they are called, exclusively feed onproducers<span>. If these consumers are human, we call them </span>vegetarians<span>. Otherwise, they are known as </span>herbivores<span>. </span>
Primary consumers<span> only obtain a fraction of the total solar energy—about 10%—captured by the producers they eat. The other 90% is used by the producer for growth, reproduction, and survival, or it is lost as </span>heat. You can probably see where this is going. Primary consumers are eaten bysecondary consumers<span>. An example would be birds that eat bugs that eat leaves. </span>Secondary consumers<span> are eaten by </span>tertiary consumers. Cats that eat birds that eat bugs that eat leaves, for instance.
<span>At each level, called a </span>trophic level<span>, about 90% of the energy is lost. What a shame. So, if a plant captures 1000 calories of solar energy, a bug that eats the plant will only obtain 100 calories of energy. A chicken that eats the bug will only obtain 10 calories, and a human that eats the chicken will only obtain 1 calorie of the original 1000 calories of solar energy captured by the plant. When you think about this way, it would take 100 1000-calorie plants—those would be enormo plants, by the way—to produce a single 100-calorie piece of free-range chicken. You are now recalling all of the plants you have ever forgotten to water in your life and feeling really, really terrible about it, aren't you? </span>
<span>The relationships among </span>producers<span>, </span>primary consumers<span>, </span>secondary consumers<span>, and </span>tertiary consumers<span> is usually drawn as a </span><span>pyramid, </span><span>known as an energy pyramid, with producers at the bottom and tertiary consumers at the top. You can see from the example above why producers are at the bottom of this pyramid. It takes a </span>lot<span> of producers for higher-trophic-level consumers, like humans, to obtain the energy they need to grow and reproduce.</span>
<span>This is the answer to the great mystery as to why there are so many plants on Earth. We will even spell it out for you because it is so important to understand: there are so many plants on Earth because </span>energy flowthrough ecosystems is inefficient. Only 10% of the energy in one trophic level is ever passed to the next. So, there you have it. We hope you feel fulfilled.
In addition to energy pyramid diagrams, ecosystem ecologists sometimes depict the relationship between trophic groups in a linear way, with arrows pointing from one organism to another. If there is only one producer, one primary consumer, one secondary consumer, and one tertiary consumer, this linear diagram is called a<span> food chain</span><span>. Food chains help ecologists and students visualize the interactions between organisms in an ecosystem. As always seems to be the case, it isn’t ever that simple. In fact, trophic interactions among organisms in an ecosystem are often really complex. It’s rare that an ecosystem only has one species at each trophic level. Usually, there are multiple producers that are eaten by multiple primary consumers. Some consumers eat different kinds of producers. Likewise, secondary consumers sometimes eat producers as well as primary consumers. These are known as </span>omnivores<span>. </span>
<span>These complex relationships are often depicted—if they can be figured out, that is—in a diagram called a </span>food web<span>. These diagrams can become messy indeed, depending on the size of the ecosystem and the number of interactions among trophic groups. If you like puzzles and biology, though, ecosystem ecology is the field for you. </span>
<span>Ecologists use food webs to better understand the intricate workings of the ecosystems they study. Understanding exactly who is eating whom can provide valuable information for conservation biologists as well. Such knowledge can aid in restoration efforts, species recovery projects, and preservation efforts, just to name a few instances. In any case, uncovering food webs goes a long way to understanding the first half of an ecosystem, the </span>community.
At the compensation point, the rate of CO2 production by respiration matches the rate of CO2 utilization in photosynthesis- there is no net CO2 production
. Since photosynthesis is rate limited, the rate of energy intake can be reduced in order to reach the compensation point; lowering the light intensity would slow the rate of photolysis and thus photosynthesis. Similarly, an increase in light intensity
increases the rate of photosynthesis- the CO2 level would be reduced as more inorganic CO2 is fixed, together with producing O2 as waste.
would increase the temperature of the environment- light energy is converted to heat energy which increases temperature.
lead to higher levels of humidity- the heightened temperature increases the rate of evaporation of water from tissues, and thus increases the humidity (water vapor content of the surrounding air)
Further Explanation:
Photosynthesis is a chemical pathway that’s integral to producing energy in plants and other primary producers. Energy in the form of molecules of glucose is produced from light, water and carbon dioxide while oxygen is released. This occurs in several complex steps, photosynthesis is a rate limited reaction, depends on several factors including carbon dioxide concentration, ambient temperature and light intensity; the energy is retrieved from photons, I.e. particles of light, and water is used as a reducing agent. This occurs in the thykaloids, where pigment molecules like chlorophyll reside.
Occuring in several complex steps, photosynthesis is a rate limited reaction, depends on several factors including carbon dioxide concentration, ambient temperature and light intensity; the energy is retrieved from photons, I.e. particles of light, and water is used as a reducing agent. Water supplies the chlorophyll in plant cell with replacement electrons for the ones removed from photosystem II.
Additionally, water (H2O) split by light during photolysis into H+ and OH- acts as a source of oxygen along with functioning as a reducing agent; it reduces the molecule NADP to NADPH by providing H+ ions and produces molecules of the energy storage molecule ATP through an electron transport chain. This occurs in the thykaloids, where pigment molecules like chlorophyll reside. Later, in dark reactions, NADP and NADPH are used in the Calvin cycle where monosaccharides or sugars like glucose are produced after the modification of several molecules. These store energy in their bonds, which can be released in respiration in the mitochondria.
Cells reproduce by the process of CELL DIVISION, which is the formation of an increased number of cells from a single parent cell. Mitosis is the type of cell division used for the multiplication of cells as it involves the synthesis of two identical number of daughter cells from a single parent cell.
However, certain drugs that may prevent the unregulated reproduction of cells is trying to directly affect the process of cellular division in that cell. This is because cell division is the way through which cells reproduce themselves.
not really familiar with all this but I think 1. Relative dating is where they estimate or relatively guess around how old it is so you could just put something like "an estimate of the age" or something
