week2

As a general rule of thumb, each trophic level has about level below it in the pyramid. as much energy as the trophic

1/10

DNA is composed of varying arrangements of__ different nucleotides.

4

Evaporation from the ocean Precipitation over the ocean Precipitation over the land Evaporation from soil, streams, rivers, and lakes

425,000 km3 385,000 km3 111,000 km3 30,000 km3

Why do excessive nutrient levels in Chesapeake Bay cause declining crab fisheries? (Select all that apply.)

Algal growth is excessive. oxygen is depleated

What are the main sources Of nutrients (nitrogen and phosphorus) in Chesapeake Bay?

Atmospheric deposition from transport and industry, wastewater, and agriculture

Which Of these accurately describe the degradation Of energy as it is used? (Select all that apply.)

Chemical energy in food is converted to kinetic energy in an animal. Heat energy in an animal is convened to the kinetic energy of running.

What are the benefits Of mapping and monitoring satellite-collected data or chlorophyll abundance around the world? (Select all that apply.)

Chlorophyll abundance in the ocean is an essential indicator of ecosystem health. Primary productivity is a way of measuring C02 uptake, and that information can be used to model the potential impacts on climate change.

Which Of the following are major processes in the carbon cycle?

Combustion Photosynthesis Respiration

Which statement best describes the way the quality Of energy normally changes as it moves through a system?

Energy degrades or dissipates.

Which Of the following are roles specific to enzymes? (Select all that apply.)

Enzymes dispose of cell wastes. Enzymes are molecular catalysts, regulating chemical reactions.

Which Of the following are examples Of important carbon sinks? (Select all that apply.)

Expansive boreal forests Oceans

is the term used to describe an organism that thrives in a variety Of severe or harsh conditions.

Extremophile

Why are isotopes important in environmental science?

Isotopes let us approximate past temperatures from air bubbles in ice cores.

Why is it important that carbon and nitrogen be "fixed"?

It involves converting them from a gaseous state into forms that are useful to plants and other organisms.

Match each type Of energy to its correct definition.

Kinetic- Energy in moving objects potential- Stored energy, as in a rock poised on top of a mountain Chemical- Energy stored in molecular bonds Heat- Energy transferred between objects of different temperature

Which Of the following statements about energy are true? (Select all that apply.)

Low-quality energy is not generally as easy to use as high-quality energy. A mass can have a high heat content but a low temperature.

Match the following characteristics Of water to the correct description of Why that characteristic is essential to life on earth.

Molecules are polar. -Dissolves substances easily Water remains liquid at a wide range of temperatures. -Helps organisms to function in cool and warm condition Molecules are cohesive. -Aids capillary action and surface tension

When oxygen is available, bacteria may combine ammonia (NHS) with oxygen to form (Select all that apply.)

NO nitric oxide N2O nitrous oxide N03- nitrate N02- nitrite

Rank the following carbon cycle exchanges with the process moving the most carbon at the top and the least at the bottom.

Photosynthesis by land plants Photosynthesis by marine plankt( Buming of fossil fuels Land clearing, burning

Sugar molecules Calcium carbonate Coal and oil Carbon dioxide

Plants Shells and skeletons of marine organisms Earth's sediments and rock layers Atrnosphere

Herbivore Carnivore Omnivore Scavenger Detritivore Decomposer

Plants only Flesh only Both plants and animals Dead carcasses Litter, debris, and dung Organic material remnants

In a trophic pyramid, it is observed that less energy is available at the top (top predators) as compared to the bottom (primary producers). Where does the energy go as it is used in the ecosystem? (Select all the statements that are correct.)

Producers' high-quality chemical energy is transformed to lower-quality energy forms (heat) that dissipates to the environment as organisms move. Organisms in each trophic level live and grow, which requires energy, so less energy is available to transfer up to the next level in the pyramid.

Which Of these examples correctly describe energy quality as it relates to environmental science? (Select all that apply.)

Solar and wind energy are diffuse and hard to use. The kinetic energ of wind is low-quality and hard to store efficiently.

Which Of these examples correctly describe energy quality as it relates to environmental science? (Select all that apply.)

Solar and wind energy are diffuse and hard to use. The kinetic energy of wind is low-quality and hard to store efficiently.

Acids Bases

Substances that readily give up hydrogen ions in water Substances that readily bond with hydrogen ions in water

Which Of these statements correctly describes the process Of cellular respiration? (Select all that apply.)

Sugars and oxygen are broken down to release energy, water, and carbon dioxide. Cellular respiration is basically the opposite of photosynthesis.

Since 1945, human inputs have led to more than double the amount Of nitrogen in circulation. Select all the sources Of this additional nitrogen.

Synthetic ammonia fertilizers Burning of fossil fuels in car engines and industrial furnaces nitrogen fixing soybeans

Metabolism involves

all the energy and matter exchanges that occur within a living cell or organism

A population is and a biological community is_____

all the members of a species living in a given area at the same time; all the populations living and interacting in a particular area

Primary productivity in an ecosystem relates to the

amount of biomass produced in a given area during a given time period

Which of the following statements is true regarding molecules and compounds?

both made out of atoms

The principle Of conservation Of matter states that matter

cannot be destroyed or created under normal circumstances can be converted to different forms can be recycled

-based ("organic") compounds are the foundation Of organisms.

carbon

Organic compounds are primarily made Of chains and rings of atoms.

carbon

consumers

carnivors herbivores

Table salt (NaCl) dissolves in water to form Na+ and Cr. Identify which ion is an anion and which is a cation.

cation anion

A food___ is a linked feeding series, and a food ____ is an interconnected arrangement of several predator and prey relations generally inhabiting the same ecosystem.

chain web

is the process in which bacteria use chemical bonds between inorganic elements to provide energy for synthesis Of organic molecules.

chemosynthesis

Isotopes Of oxygen, which differ in mass, are used to evaluate research. in environmental science

climate history

In a covalent bond, atoms share ___. In an ionic bond, ions are held together by the attraction of____ electrical charges.

electron opposite

Matter consists of __, which are substances that cannot be broken down into simpler forms by ordinary chemical reactions.

elements

The sun supplies which is important to living organisms because plants can capture it and convert it into a form accessible to animals.

energy

We think Of ecosystems as systems because

energy and matter flow through, and are stored in, the component parts

The first law Of thermodynamics states that ___

energy cannot be created ar destroyed under normal conditions

There are more rabbits than foxes in an ecosystem because

energy is degraded and dissipated within a trophic level and as it is transferred to successively higher trophic levels in the pyramid

things on a cell

enzymes wall or membrane nucleus

We can characterize the hydrologic cycle in terms Of a series Of steps. Recreate this series with evaporation at the top followed by the next steps in the sequence in descending order.

eva condens precipitation runoff

Carbon and nitrogen involves capturing atmospheric forms and converting them into forms usable by both plants and animals.

fixing

Carbon is stored for very long periods Of time in the longest storage times.) (Select the two answers with the

form of coal and oil below the earth's surface Coal and oil are made up of the carboniferous remains of plants or microorganisms that are compressed and chemically altered over millions of years. shells and skeletons of marine organisms at the bottom of the ocean

producers

green plant algae

Something different about the phosphorus cycle, as compared to both the nitrogen and carbon cycles, is that it

has no gaseous or atmospheric phase

Undersea explorations in the 1970s revealed chemosynthetic communities with organisms capable Of using the chemical bonds between the inorganic elements Of energy for synthesis Of organic molecules. to provide

hydrogen sulfide (H2S) or hydrogen gas (H2)

Entropy tends to over time in natural systems.

increase

Positively or negatively charged atoms are called

ions

The original Latin meaning Of the term species is____

kind

Heat stored in the ocean is Of

low-level energy

____ involves all the energy and matter exchanges that occur within a living cell or organism.

metabolism

Differing numbers of which particle can make different isotopes Of an element?

neutrons

The nucleus of an atom contains neutrons and protons. A "cloud" of electrons surrounds the nucleus.

neutrons and protons

Being "fixed" by bacteria,______ is important to living things because it is an essential component of proteins, enzymes, DNA, and many other organic molecules.

nitrogen

The four major categories Of organic compounds in living things are lipids, carbohydrates, proteins, and

nucleic acid

most residence time for water

ocean

In general, an ecosystem includes

organisms and nonliving factors in their environment

A(n) __atom gives up one or more electrons, and a(n)__ atom gains electrons.

oxidized reduced

The four elements that make up more than 96 percent of the mass of most living organisms are

oxygen, carbon, hydrogen, and n itrogen

The__scale is used to represent hydrogen ion concentrations in water, and differentiates acids and bases.

pH

Phosphorus is an important matter Of concern because (Choose all that apply.)

phosphorus is a key nutrient most phosphorus in ecosystems comes from rocks and mineral sources that are in limited supply phosphorus can lead to environmental pollution

Green plants, algae, and some bacteria capture solar radiation and convert it to organic molecules in a process called

photosynthesis.

Green plants and algae are categorized as primary ___, whereas animals are considered ___ because they must feed on other organisms or their remains.

producers consumers

Acids or bases can cause environmental problems because they

react readily with living tissues

The ___ law of thermodynamics recognizes that entropy (disorder, or loss of energy or organization) tends to increase in nature.

second

An element's atomic number involves the number Of protons in an atom because (Select all that apply.)

the number of neutrons can vary (producing different isotopes) the number of protons does not vary

An organism's feeding status in an ecosystem can be expressed as its

trophic level

True or false: Bacteria play an important part in driving the global nitrogen cycle.

tru