Biology problems, energy flow, quick and detailed solutions

The information of the problem is incomplete, and it is solved in two situations.

1. The energy flow efficiency is calculated according to 10%. 1 4 o'clock: snake weight gain 1kg, need rat:, toad:(, bug:, grass (rat + insect):

75kg+。Set grass (sheep + insect + rat) as xkg, the assimilation amount of sheep: , the assimilation amount of people:

3 4 hours: snake weight gain 1kg, need rat:, toad:, worm: 25kg, grass (rat + worm): 325kg. Grass (sheep + insects + rats) is still xkg, the assimilation of sheep: , the assimilation of people:

2. The energy flow is calculated according to 20%. [I really don't want to write.。。。 It's 2kg... Just do the math according to the above algorithm...

Before changing the food ratio, the snake gained 1kg of weight and consumed grass to 3 4 x 5 x 5 x 5 + 1 4 x 5 x 5

After changing the food ratio, the snake gained 1kg of weight and consumed 1 4 x 5 x 5 x 5 x 5 + 3 4 x 5 x 5

The amount of grass saved after changing the food ratio is:

3/4 x 5 x 5 x 5 + 1/4 x 5 x 5 —1/4 x 5 x 5 x 5 - 3/4 x 5 x 5

The surplus of 50 kg of grass can flow into the human body through the sheep: 50 x 20% x 20% = 2kg

Hello, the food chain and the food web are the channels through which energy flows. In ecosystems, such as the food chain: grass rabbit eagle, rabbit eats grass, the material and energy stored by the grass for photosynthesis enters the rabbit's body, the eagle eats the rabbit, and the matter and energy stored in the rabbit's body goes to the eagle's body.

Therefore, the material energy in the ecosystem flows along the food chain and the food web.

1.Knowing the energy (or biomass) of the lower trophic level, find the maximum value of the energy (or biomass) obtained by the higher trophic level organisms. Calculated by 20% of the maximum transfer efficiency, i.e., the energy (or biomass) of the lower trophic level multiplied by (20% to the nth power) (n is the number of arrows in the food chain from the lower trophic level to the trophic level to be calculated).

2.Knowing the energy (or biomass) of a higher trophic level, find the minimum value of energy (or biomass) that a lower trophic level should have. Calculated as 20% of the maximum transfer efficiency, i.e. the biomass at the lower trophic level is at least the energy (or biomass) at the higher trophic level multiplied by 5n.

3.Knowing the transmission route and efficiency of energy, calculating the energy (or biomass) of the relevant organism. On the basis of determining the energy transfer efficiency and transfer path, it can be calculated according to the corresponding energy transfer efficiency and transfer path.

How is the flow of energy in a food web calculated.

June 5 is World Environment Day, and the theme of World Environment Day in China today is "Building an Ecological Civilization and Sharing a Green Future".Grassland is an important part of the green ecological environment. The food web of a grassland ecosystem is shown in the figure.

1) The simplicity of the food web in the figure makes the grassland ecosystem less capable and less stable. In addition to the biota shown in the figure, the biological composition of the ecosystem should be sufficient to ensure the proper functioning of its material cycle.

2) If the grass in the figure can provide 10,000 kJ of energy, and the energy transfer efficiency between trophic levels is 10% to 20%, then the lowest and highest energy values that can be obtained from the trophic level occupied by the eagle are kj and kj. If snakes are removed and the number of foxes remains the same, the number of eagles in the grassland will be greatly reduced or lost if alien organisms invade the area.

3) The interspecific factors influencing the change of rabbit population in the figure are and competition. If the k value of a rabbit population is 1000 in a certain year, and the amount of grass consumed by 1 rabbit and 4 rats is equal, and the number of rats increases by 400 in the following year, the k value of the rabbit population becomes one. When the population in the area is surveyed using the marker recapture method, if some of the marked individuals move out, the results will be filled in "high" or "low").

4) When the grassland is dry, the water intake of rabbits decreases, and the osmotic pressure of the extracellular fluid in the body causes osmoreceptor excitation, increases the release of antidiuretic hormone, and then causes an increase in water reabsorption, reducing the amount of urine to maintain the water balance in the body.

Answers: (1) Self-regulation (or feedback regulation) of resistance decomposers.

2) 10 400 Increase in biodiversity (or species diversity).

3) Predator 900 is on the high side.

4) Elevated hypothalamus, renal tubules, collecting ducts.

1.The source of energy flow: sunlight energy.

2.Input starting point for energy flow: (photobiome) Related physiological process: Photosynthesis of green plants converts light energy into chemical energy. Total value entered: Green plants through photosynthesis.

3.Transfer of energy Form of transfer: in the form of organic matter. Pathways: along the trophic structure of the ecosystem – food chain and.

4.Utilization and loss of energy: Some of the energy input to this trophic level is lost in the form of heat during its respiration.

The maximum amount of plants consumed, the energy transfer efficiency is calculated as 10%.

One-half of human food comes from plants, which means that 1kg of human weight gain requires 10*1 2=5kg of plants;

A quarter came from small carnivores, indicating that 1 kg of human weight gain requires 10 * 10 * 10 * 1 4 = 250 kg;

A quarter comes from beef and mutton, indicating that 1kg of human weight gain requires 10*10*1 4=25kg of plants;

The sum of the three requires 280kg of plants to gain 1kg of human weight.

People gain 1kg of weight due to eating plants.

Let the energy of the plant be p, and the minimum transfer efficiency is 10%, so px10%=

So p=5kg

So consume up to 5kg of plants

If you don't understand, ask me again.

According to the different digestibility of individuals and the different energy consumed for digestion caused by the way food is cooked, please give a more detailed solution to this problem, if it is eaten, the weight gain is 1kg*1 2=