The answer is 4. In a certain community, animals usually have the same environmental requirements in order to survive. Having the same requirements for survival could lead to competition wherein these animals compete with other animals for the same food or habitat in order to survive.

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The answer is 3. Predators are biotic factors that affect the size of a population. These predators prey on any animal below their food chain and can cause an imbalance n the size of a certain population.

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The answer is 3. A constant source of energy is needed in order for a certain ecosystem to survive. Energy is flowed from organism to organism in the ecosystem by food webs or pyramids wherein it is transferred from one organism to another by consuming them as food.

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The answer is 4. Competition is a type of interaction between two or more organisms which compete for the same need in order to survive. This need may be in terms of food or habitat or other resources.

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The answer is 4. Certain chemical elements including carbon and oxygen must be cycled between organisms and the environment because this is how a balanced ecosystem is achieved. The cycle of exchange between carbon dioxide and oxygen is needed to maintain respiration between the two.

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The answer is 1. In a certain hierarchy of organisms consuming each other, every level of the food chain release energy in the form of heat. As the food chain reaches the latter consumer, energy transferred becomes decreased.

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As seen in the graph, the pH of Adirondack lakes decreased from 1880 to 1980. The decrease was due to the contribution of rainwater in the lakes that made them decrease or made them acidic and caused also a decrease in biotic organisms.

As seen in the graph, the decrease in pH or the acidic change also caused a significant decrease in population of the trout, bass and mussels. The species located in this area was not able to adapt to the change in environment.

The answer is 1. Producers are the primary source of food in an ecosystem. This is where transferring energy all starts. After being eaten by carnivores or consumers, energy is transferred from organism to another.

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The answer is 1. An organisms niche describes the organisms role or position in the habitat as well as how resources are used and its role in the community. This means that each species of bird may consume different types of food or habitat preventing the cause of competition.

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The presence of rocks in its habitat would directly affect the survival of the fish. Rocks may affect the survival of the fish because the presence of this may open an opportunity for fish eating birds to prey on them.

The answer is 1. Heterotrophs are organisms which cannot produce its own food and therefore rely on other organisms as their food source. Usually plants are considered the one that heterotrophs rely on. Herbivores are organisms that consume only plants for food.

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The answer is 1. Corn plants, in this food chain, are considered to be primary producers. Primary producers are organisms such as plants or algae that have the ability to produce their own food by using energy from the sun for the production of carbohydrates which serve as their food.

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The answer is 3. Predators animals that kill their prey and eat them. This is done in ecosystems in order to survive. The predator which is the one on top of the food chain captures and devours their prey for food.

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The answer is rabbit. Heterotrophs are types of animals which rely on primary producers for their survival. In the food web shown, rabbits can also be a part of population A because rabbits are also made as a prey for predators.

rabbit

Primary producers are organisms such as plants or algae that have the ability to produce their own food by using energy from the sun for the production of carbohydrates which serve as their food. They are located at the bottom of the food pyramid because they are the one consumed by primary, secondary and tertiary consumers.

The answer is 1. As seen in the graph, the relationship shows that as sewage wastes increases, the oxygen content decreases. This is reasonable because sewage wastes contain hazardous chemicals that poison and harm the oxygen content of the population.

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The answer is 2. As seen in the diagram, there was a decrease in population for the whitefish between the years 1955 and 1960.

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the answer is carp. According to the graph seen, carps were the one that still managed to survive despite lack of oxygen content. There was still an increase in population of the carps despite having changes in the environment.

Carp

The impact of increased sewage levels on the lake caused a significant change in the population of certain species living there. As seen in the graph, levels of whitefish, trout and walleye decreased as the oxygen level also decreased.

APPROPRIATE SCALE

PLOTTING

The answer is 3. As seen in the data given, the year 1924 had an increase of almost 100,000 which was the highest among the recorded years.

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A possible action would be the decrease in hunting activity. Another possibility would be the increase in mating and source of food. Maintaining the natural habitat is also a big help for the community.

The answer is 4. Since there is a change in the environment, both animals and plants will try to adapt to these changes and then eventually cope up with these changes in order to maintain survival.

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The answer is 3. A biosphere is the part of the earth that includes all life forms as well as all nonliving things and their environment wherein they interact with each other.

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Food chain of grasses, grasshoppers, spiders and birds.

the answer is 2. According to the data given for the month of May, the quantity of the population size are as follows:
Grasses: 7,000
2: Grasshoppers: 1,000
3. Birds: 250
4. Spiders: 75

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The answer is 2. Since hunting mountain lions by hunters have been a recreational activity for them, as well as a reason to prevent harm in a population, hunters have been hunting mountain lions more than deer since they are the ones that bring harm to the community.

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The answer is 2. Human intervention has always been a factor in the survival of animals or species in the world. Here in the passage, the bounty greatly affected the urge of hunters to kill those mountain lions in order to protect the deer as well as their community.

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Biodiversity is composed of different biotic and abiotic forms forming different ecosystems. It is a form of measurement for the different genes, species and the ecosystem. It is important to maintain biodiversity because without homeostasis, the whole ecosystem would experience a certain damage in how the certain ecosystem functions.

Habitat is a place wherein both living and non-living things reside to grow and reproduce. It is also the place where they get to interact with each other for their survival, while an organisms niche describes the organisms role or position in the habitat as well as how resources are used and its role in the community.

One effect that may occur by reintroducing the wolf would be competition. Since both the cayote and wolf have the same preference in food and habitat, this will create a competition between the two species.

The cayote is considered a limiting factor in the mountains because with the introduction of the wolves, there would be a build up of competition between the two species without making sure if what species will survive.

The reintroduction of wolves could create a new for of habitat in which new species could later adapt to. Reintroducing wolves could also decrease the population of deer in a certain population to prevent overpopulation.

The answer is 2. With a limited amount of carrying capacity, having a much more actual population size would create more competition in certain population. This is because of the limited amount of food resources available in a certain population.

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The capability of an ecosystem to have three carrying capacities is based on:
1) population size
2. consumed resources
3. available resources