Glossary

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Term Term description
macroflora

 

All of the plants occurring in a particular area that are large enough to be seen with the naked eye.

 

macronutrients

Any substance, such as carbon, hydrogen, or oxygen, that is required in large amounts for an organism's healthy growth and development. They are usually obtained through the intake of food, water, or air.

magma

Hot liquid rock material under the Earth's crust that comes to the surface through volcanic eruptions, and form igneous rocks when cooled.

Marine Protected Areas

Areas of the oceans or Great Lakes that are protected by law for a conservation purpose.

mass

A body of matter with no particular defined shape and having weight. A molecule has a very low mass, while an elephant has a relatively high mass.

matter

Something that occupies space, has mass, and can exist ordinarily as a solid, liquid, or gas.

mean

The simple mathematical average of a set of two or more numbers.

mesophyll

The tissues of a leaf that carry on photosynthesis, consisting of the palisade layer and the spongy parenchyma.

mespohyll

The photosynthetic tissues of a leaf, located between the upper and lower epidermis.

metabolic system

The set of life-sustaining chemical transformations within the cells and organ systems of living organisms. The metabolic system of a particular organism determines which substances it will find nutritious and which poisonous.

metabolism

All the energy and matter exchanges that occur within a living cell or organism; collectively, the life processes of organisms.

metabolism

The process used by an organism to extract energy from food.

metalloid

A chemical element with properties between those of metals and non-metals. These include boron, silicon, germanium, arsenic, antimony, and tellurium. They can combine with a metal to form a metal alloy, and often act as biological toxins or nutrients, depending on the concentration.

metamorphic

A rock type that results from a parent rock type changing under the influence of heat, pressure, or some other agent without passing through a liquid phase.

metamorphic rocks

Rocks that are created by the physical and chemical alteration of heat and pressure of an existing igneous or sedimentary material.

methane

CH4, an odorless, colorless, flammable gas, the major constituent of natural gas, a fossil fuel that is used by humans.

methanogenesis

The production of methane (CH4), especially through the action of methanogens in oxygen-free environments. Methanogens are microorganisms produce methane gas as a byproduct of anaerobic respiration.

methanogens

Microorganisms that produce methane as a metabolic byproduct in anoxic conditions. They are classified as archaea, a domain distinct from bacteria, and are found in the stomachs of cows, in swamp mud, and in other environments in which oxygen is not present.

methionine

An essential amino acid (C5H11NO2S) containing sulphur, which occurs in many proteins. It is not synthesized by the human body, and must be absorbed from food.

microalgae

Tiny unicellular algae visible only under a microscope.

microbe

Microbes are single-cell microscopic organisms that include bacteria, archaea, fungi and protists. They occur in every habitat on Earth.

microbe

A term for tiny creatures that individually are too small to be seen with the unaided eye. Microbes include bacteria, archaea, fungi and protists.

microbial

Pertaining to a minute life form; a microorganism. Typically described as something that is too small to be seen with the naked eye, often bacteria but also including arachea, algae, fungi, and protozoa.

microflora

The community of microorganisms, including algae, fungi, and bacteria that live together in or on another living organism, or in a particular habitat.

micronutrient

Vitamins and minerals that are essential in minute amounts (< 100 mg/day) to the growth and health of organisms.

microorganism

An organism that can be seen only with the aid of a microscope. Microorganisms include bacteria, protozoans, algae, and fungi.

Milankovitch

Variations in the Earth's eccentricity, axial tilt, and precession comprise the three dominant cycles, collectively known as the Milankovitch Cycles, named after Milutin Milankovitch who discovered these phenomena.

Millennium Ecosystem Assessment Report

The Millennium Ecosystem Assessment (MA), called for by the United Nations Secretary-General Kofi Annan in 2000 to assess the consequences of ecosystem change for human well-being and the scientific basis for action needed to enhance the conservation and sustainable use of those systems and their contribution to human well-being. The MA has involved the work of more than 1,360 experts worldwide. Their findings provide a state-of-the-art scientific appraisal of the condition and trends in the world’s ecosystems and the services they provide (such as clean water, food, forest products, flood control, and natural resources) and the options to restore, conserve or enhance the sustainable use of ecosystems.

minerals

A naturally occurring crystalline substance that is generally inorganic, occurs naturally, is solid, has a specific chemical composition and an ordered atomic arrangement.

mini-grid

Small electrical networks that are used to distribute alternate electric current within a small village or neighborhood. Mini-grids are usually supplied by a single power generation station (e.g. Micro-Hydro power plant, Wind turbine, combustion engine running on Biogas or a Photovoltaic array).

molecular polarity

A property of molecules that have a slight positive charge on one side and a slight negative charge on the other.

molecule

A combination of two or more atoms bound together, that has different qualities than the individual atoms.

mollusks

Mollusks were among the first inhabitants of the Earth- many have been found in rocks that date back over 500 million years. Most mollusks have a soft, skin-like organ covered with a hard outside shell and live on land or in water.

monoculture

The cultivation or growth of a single species of crop or organism especially on agricultural or forest land.

monoculture

The cultivation or growth of a single species of crop or organism especially on agricultural or forest land.

moral goals

Aims toward which human beings direct their action for the sake of a morally good result.

moral principles

Standards or rules that help define right and wrong human actions.

moral virtues

Features of a person’s character that contribute to the well-being of persons, human societies, and the natural world.

Muslim

Of or relating to the religion, law, or civilization of Islam; an adherent of Islam.

mutation

 

A change, either spontaneous or by external factors, in the genetic material of a cell; mutations in the gametes (sex cells) can be inherited by future generations of organisms. Mutations are the basis of evolutionary change.

 

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