EnSci

environment

from the French environner which means to encircle or surround.

Environmental Science

The systematic study of our environment and our proper place in it.

Environmental Engineering

Environmental Engineering

branch of engineering that aims to improve the quality of environment and promotes protection of people from adverse environmental effects like pollution.

Ecology

defined as the scientific study of relationships between organisms and their environment.

carbon-based (organic) compounds

The foundations of organisms

Matter

Everything that takes up space and has mass.

Solid, Liquid, Gas and Plasma

Four states of matter

Conservation of Matter

“Matter is neither created nor destroyed, rather, it is recycled over and over again.”

Elements

Substances that cannot be broken down into simpler forms by ordinary chemical reactions.

OXYGEN, CARBON, HYDROGEN, AND NITROGEN.

Four Elements responsible for more than 96% of the mass of most living organisms

Atoms

Smallest particles that exhibit the characteristics of an element.

Protons and neutrons

have approximately the same mass and they are clustered in the nucleus in the center of the atom.

Electrons

smaller compare to the other particles. They orbit the nucleus at the speed of light.

Atomic number

is the characteristic number of protons per atom.

Atomic mass

is the sum of protons and neutrons.

Isotopes

are forms of an element that differ in atomic mass.

Compounds

substances composed of different kinds of atoms

Molecules

a pair or group of atoms that can exist as a single unit

Anions

Cations

2 types of Ion

Acids

are substances that readily give up hydrogen ions in water

Bases

are substances that readily bond with H+ ions.

pH

describes the strength of an acid and base.

Lipids

Carbohydrates

Proteins

Nucleic Acid

Four major categories of organic compounds in living things

Nucleotides

carry information between cells, tissues, and organs and the sources of intracellular energy. It forms long chains called ribo nucleic acid (RNA) or deoxyribo nucleic acid (DNA) that are essential for storing and expressing genetic information.

adenine, guanine, cytosine, and thyamine

Four kinds of nucleotides that occur in DNA

Cells

Minute compartments within which the processes of life are carried out.

single celled organisms

Some examples of this organisms are bacteria, some algae, and protozoa.

Enzymes

a special class of proteins that carry out all the chemical reactions required to create various structures. They also provide energy and materials to carry out cell functions, dispose of wastes, and perform other functions of life at the cellular level. They are molecular catalyst because they regulate chemical reactions without being used up or inactivated in the process.

Metabolism

the multitude of enzymatic reactions performed by an organism.

Energy

The ability to do work, such as moving matter over a distance or causing a heat transfer between two objects at different temperatures.

Kinetic

Potential

Chemical

Heat

Types of Energy

Kinetic Energy

energy contained in moving objects

Potential Energy

stored energy that is dormant but available for use.

Chemical Energy

stored in the food that you eat and the gasoline that you put into your car

Heat

the energy that can be transferred between objects of different temperature.

One joule (J)

is the work done when one kg is accelerated at one meter per second per second.

One calorie

is the amount of energy needed to heat one gram of pure water one degree Celsius.

Thermodynamics

A study that deals with the transfer of energy in natural processes.

It deals with the rates of flow and the transformation of energy from one form or quality to another.

First law of thermodynamics

States that energy is conserved. It is neither created nor destroyed under normal conditions

Second law of thermodynamics

States that, with each successive energy transfer or transformation in a system, less energy is available to do work. Energy is degraded to lower-quality forms, or it dissipates and is lost, as it is used.

Chemosynthesis

is the process in which bacteria use chemical bonds between inorganic elements, such as hydrogen sulfide (H2S) or hydrogen gas (H2), to provide energy for synthesis of organic molecules.

Photosynthesis

converts radiant energy into high-quality chemical energy in the bonds that hold together organic molecules.

Ecology

the scientific study of relationships between organisms and their environment.

Species

refers to all organisms of the same kind that are genetically similar enough to breed in nature and produce live, fertile offspring.

Population

consists of all the members of a species living in a given area at the same time.

Biological Community

All of the populations living and interacting in a particular area.

Ecosystem

is composed of a biological community and its physical environment.

Abiotic factors

nonliving components such as climate, water, minerals, and sunlight

Biotic factors

examples are organisms and their products (secretions, wastes, and remains) and effects in a given area.

Productivity

One of the major properties of an ecosystem. The amount of biomass (biological matter) produced in a given area during a given period of time.

Food Chain

A linked feeding series.

Food Web

Interconnection of individual food chains.

Trophic Level

From the Greek trophe which means “food”. An organism’s feeding status in an ecosystem.

Producers

Organisms that photosynthesize, mainly green plants and algae.

Consumers

organisms that consumes the chemical energy harnessed by the producers.

Herbivores

plant eaters, e.g. goat, cow, horse, grasshopper, etc.

Carnivores

flesh eaters, e.g. lion, hyena, caracal, wolf, etc.

Omnivores

eat both plant and animal matter, e.g. man

Scavengers

Organisms that clean up dead carcasses of larger animals such as crows, jackals, and vultures.

Detritivores

Consume litter, debris, and dung such as ants and beetles.

Decomposer

Organisms that complete the final breakdown and recycling of organic materials such as fungi and bacteria. These microorganisms are second in importance to producers because without their activity nutrients would remain locked-up in the organic compounds of dead organisms and discarded body wastes, rather than being made available to successive generations of organisms.

Ecological Pyramids

A graphical representation of the relationship between different organisms in an ecosystem.

Pyramid of numbers

Pyramid of biomass

Pyramid of productivity

Types of Ecological Pyramid

Pyramid of numbers

Presents the number of organisms in each trophic level without any consideration for their size.

Pyramid of biomass

Presents the total mass of organisms at each trophic level. This type of pyramid is largest at the bottom and gets smaller going up, but exceptions do exist.

Pyramid of productivity

Presents the total amount of energy present at each trophic level, as well as the loss of energy between trophic levels. The most widely used type of ecological pyramid. Unlike

Hydrologic Cycle

The path of water through our environment.

Water

responsible for metabolic processes within cells, for maintaining the flows of key nutrients through ecosystem and for global-scale distribution of heat and energy.

Evaporation

As water is heated by the sun, surface molecules become sufficiently energized to break free of the attractive force binding them together, and then evaporate and rise as invisible vapor in the atmosphere.

Transpiration

Water vapor is also emitted from plant leaves by a process called transpiration. Every day an actively growing plant transpires 5 to 10 times as much water as it can hold at once.

Condensation

As water vapor rises, it cools and eventually condenses, usually on tiny particles of dust in the air. When it condenses it becomes a liquid again or turns directly into a solid (ice, hail or snow). These water particles then collect and form clouds

Precipitation

in the form of rain, snow and hail comes from clouds. Clouds move around the world, propelled by air currents. For instance, when they rise over mountain ranges, they cool, becoming so saturated with water that water begins to fall as rain, snow or hail, depending on the temperature of the surrounding air.

Runoff

Excessive rain or snowmelt can produce overland flow to creeks and ditches. Runoff is visible flow of water in rivers, creeks and lakes as the water stored in the basin drains out

Percolation

Some of the precipitation and snow melt moves downwards percolates or infiltrates through cracks, joints and pores in soil and rocks until it reaches the water table where it becomes groundwater.

Groundwater

Subterranean water is held in cracks and pore spaces.

Carbon Cycles

begins with the intake of carbon dioxide by photosynthetic organisms. Carbon (and hydrogen and oxygen) atoms are incorporated into sugar molecules during photosynthesis. Carbon dioxide is eventually released during respiration, closing the cycle. The carbon cycle is of special interest because biological accumulation and release of carbon is a major factor in climate regulation.

Nitrogen Gas

Makes up 78% of atmosphere; can be fixed by bacteria, cyanobacteria, some marine algae.

Ammonia

Gaseous form; corrosive; common agricultural fertilizer that bonds with H+ to form NH4.

Ammonium

Directly usable by plants; positive charge helps adhere to clays in soils.

Nitrite

Ion with negative electrical charge; a step in nitrification process (conversion of NH4 to NO3); toxic to plants; usually present temporarily or in low quantities.

Nitrate

Directly usable by plants; products of nitrification.

Organic Nitrogen

Diverse compounds, such as proteins; must be converted to NH4 for use by plants. Organic to inorganic transition is mineralization.

Nitrogen Oxides

Various combinations such as NO2 (nitrogen dioxide), NO (nitric oxide), and N2O (nitrous oxide); fuel combustion in vehicles and industry produces most NOx; rainfall washes NOx into soils and waterways. NO2 and N2 also result from denitrification by bacteria.

Phosphorus

the most important among the many elements released to ecosystem from rock formations because it is often limited in supply. It is also a key component of proteins, enzymes, and tissues.

Adaptation

The acquisition of traits that allow a species to survive in its environment.

Acclimation

When an individual organism can respond immediately to a changing environment.

Genetic traits

passed from generation to generation and allow a species to live more successfully in its environment. This process of adaptation to environment is explained by the theory of evolution.

Evolution

the basic idea is that species change over generations because individuals compete for scarce resources.

Natural Selection

the process of better-selected individuals passing their traits to the next generation.

Mutations

changes to the DNA coding sequence of individuals that occurs occasionally, and the changed sequences are inherited by offspring.

Physiological stress

Competition

Predation

Luck

limiting factors

Critical Factor

According to the chemist Justus von Liebig (1840), the single factor in shortest supply relative to demand determining where a species lives.

Tolerance Limits

each environmental factor has both minimum and maximum levels beyond which particular species cannot survive or is unable to reproduce.

Habitat

the place or set of environmental conditions in which a particular organism lives.

Ecological Niche

describes both the role played by a species in a biological community and the set of environmental factors that determine its distribution.

Generalists

species that tolerate a wide range of conditions or exploit a wide range of resources. Example: Species that thrive in broad variety of environments such as weedy species or pests (rats, cockroaches, or dandelions).

Specialists

species that have a narrow ecological niche. Examples are Giant Panda and Giant Saguaro.

Speciation

The development of a new species.

Allopatric Speciation

speciation that occurs when populations are geographically separated.