Question 1

The hydrologic cycle collects,purifies,and distributes the earth's fixed supply of water.​

Accepted Answer

The hydrologic cycle involves the continuous movement of water between the Earth's surface and atmosphere, which includes processes such as evaporation, precipitation, and groundwater recharge. It helps to maintain a fixed supply of water on Earth and plays a crucial role in regulating the Earth's climate and supporting life.

Question 2

Human activities affect the phosphorus cycle by greatly increasing the amount of phosphorus stored in the earth,reducing the amount available for plant growth.

Accepted Answer

Human activities, such as the use of fertilizers and detergents, actually increase the amount of phosphorus in the soil and water bodies, which can lead to eutrophication and harm aquatic ecosystems, rather than reducing the amount available for plant growth.

Question 3

Raising fish in a series of aquariums under varied conditions is an example of field research.​

Accepted Answer

Raising fish in aquariums is an example of laboratory research, not field research. Field research involves studying organisms in their natural habitats, not in controlled environments like aquariums.

Question 4

Plants utilize a portion of their gross primary productivity (GPP)for respiration.

Accepted Answer

Plants, like all living organisms, use a portion of their GPP for respiration. This is necessary to maintain their basic metabolic functions and to provide energy for growth and reproduction. The remaining GPP can be used for plant growth and development, such as producing leaves, stems, and flowers, or can be stored as biomass.

Question 5

Human activities have affected the sulfur cycle through the burning of sulfur-containing coal and oil.​

Accepted Answer

The burning of sulfur-containing coal and oil releases sulfur dioxide into the atmosphere, which can then react with other chemicals to form acid rain, leading to alterations in the sulfur cycle.

Question 6

Water contracts when it freezes,making ice more dense than water.​

Accepted Answer

When water freezes, its molecules arrange themselves in a crystalline structure, which creates more space between the molecules than in liquid water. This expansion causes ice to be less dense than water, which is why ice floats.

Question 7

Sometimes ecologists carry out controlled experiments by isolating and changing a variable in part of an area and comparing the results with nearby unchanged areas.

Accepted Answer

Ecologists do often use controlled experiments by manipulating a variable in one area and comparing the results to a control area.

Question 8

Only about 0.024% of the earth's vast water supply is available to humans and other species as liquid freshwater.​

Accepted Answer

This statement is true. The majority of the earth's water supply is saline or frozen in ice caps and glaciers, leaving only a small percentage as liquid freshwater available for human use.

Question 9

Despite the open ocean's low net primary productivity (NPP),it produces more of the earth's biomass per year than any other ecosystem or life zone.

Accepted Answer

Although the open ocean has a low NPP, it covers a vast area and therefore produces the highest amount of biomass per year compared to other ecosystems.

Question 10

The process by which cells are able to convert glucose into useable energy using oxygen is known as aerobic transpiration.​

Accepted Answer

The process is known as aerobic respiration, not aerobic transpiration. Aerobic respiration is the process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.

Question 11

Human activities affect the hydrologic cycle by making changes to the land surface that reduce infiltration and increase runoff.

Accepted Answer

Human activities such as urbanization, deforestation, and agriculture can lead to impervious surfaces and soil compaction, which reduces infiltration and increases surface runoff. This can lead to altered streamflow patterns, increased flood risk, and reduced groundwater recharge.

Question 12

Water has the ability to filter out wavelengths of the sun's ultraviolet radiation that would harm some aquatic organisms.

Accepted Answer

This statement is true. Water can act as a natural sunscreen for aquatic organisms by filtering out harmful UV radiation. This is especially important for organisms living in shallow water or near the surface of the water where they are more exposed to UV radiation.

Question 13

Water exists as a liquid over a wide range of temperatures because of the lack of attractive forces between its molecules.

Accepted Answer

Water molecules have strong hydrogen bonds that attract each other, causing them to stick together and thus remain in liquid form over a wide range of temperatures.

Question 14

Detritivores are consumers that release nutrients from the dead bodies of living organisms and return them to the soil,water,and air.

Accepted Answer

The answer of Detritivores are consumers that release nutrients from...

Question 15

The amount of carbon dioxide in the atmosphere is affected by the carbon cycle.

Accepted Answer

The carbon cycle involves the movement of carbon between living organisms, the atmosphere, oceans, soil, and rocks. Human activities such as burning fossil fuels disrupt the natural balance of the carbon cycle, leading to an increase in atmospheric carbon dioxide concentration, which can contribute to climate change. Therefore, the carbon cycle has a direct impact on the amount of carbon dioxide present in the atmosphere.

Question 16

Lightning is one of the natural mechanisms by which atmospheric nitrogen is converted to ammonia or ammonium ions.

Accepted Answer

Lightning provides the energy and high temperatures needed for atmospheric nitrogen (N2) to be broken down and combined with oxygen (O2) to form nitrogen oxides (NOx). These nitrogen oxides can then react with water (H2O) to form nitric acid (HNO3), which can either dissolve and be deposited in rainfall or be taken up by plants and soil to form ammonium ions (NH4+).

Question 17

Omnivores are animals that feed only on the flesh of other animals.

Accepted Answer

Omnivores are animals that feed on both plants and animals.

Question 18

Because the earth does not get significant inputs of matter from space,its essentially fixed supply of nutrients must continually be recycled to support life.

Accepted Answer

Nutrients such as carbon, nitrogen, and phosphorus are continuously cycled through the earth's systems, as there is no significant input of these elements from space. This recycling of nutrients is vital for supporting life on earth. Therefore, statement A is true.

Question 19

A deer is both a primary consumer and in the second trophic level.​

Accepted Answer

A deer is a primary consumer because it mainly eats plants, which are producers. As a primary consumer, it is also in the second trophic level, as it consumes producers (first trophic level) and is consumed by predators (third trophic level).

Question 20

Liquid water changes temperature quickly because only a small amount of heat is required to produce a large change in temperature.​

Accepted Answer

Liquid water has a high specific heat capacity, meaning it requires a relatively large amount of heat to change its temperature.

Quiz 3: Ecosystems - What Are They and How Do They Work