A sense organ found in vertebrates that can control balance and the detection of sounds in the external environment.

Also known as the tympanic membrane and connecting the external and inner ear, this membrane is responsible for detecting sound waves travelling up the ear.

An area of the environment that tends to suit a species' long term survival and welfare. Factors in the external environment of an organism cause abiotic stress, which prevent the species' population from exploding in numbers, and according to the laws of natural selection, those in a population least suited to their environment are less likely to survive. When an ecological niche is overpopulated, this theory of natural selection will come into play, where those most suited to the ecological niche will most likely survive and pass on their genetic information and contribute to the continually adapting gene pool.

A way of measuring feeding relationships between organisms, either by biomass, population or energy.

Also known as bionomics, ecology involves the study of organisms in relation to their environment

Ecospecies

Pertaining to a species which has a diversified over time, where each sub-species involved is still capable of reproducing fertile offspring with one another.

The volume of area where biological matter can exist, slightly above, on or below ground level.

Description of an area with its biotic and abiotic factors is similar, such as grassland, woodland etc.

An indication of a species' ecological niche, where organisms are in abundance in the centre of the geographical niche, where over distance the density of the organism decreases in the less favourable areas.

Cold blooded animals, those who cannot regulate their body temperature.

Edaphic Factor

Abiotic factors involving the soil, such as its pH and chemical concentrations.

Animals without teeth.

Actions carried out by nervous impulses and hormones that are activated by receptors.

Nervous impulses that travel from the Central Nervous System.

Effluent

An outlet of liquid.

The expulsion of excess and unused food from within the body.

Otherwise known as the ovum. Otherwise, externally, an egg can be deposited by parents which soon develop into offspring. Some domesticated birds do not lay eggs.

See Ovum

Ejaculation

The expulsion of semen from the male penis for reproductive purposes, where semen will attempt to fertilise the female gamete and fuse to form a zygote.

A type of plankton where its movement is assisted by oil droplets present in the organism assisting in its buoyancy.

A plastid that stores oil.

Such an organ is found in the electric eel, these organs are capable of discharging an electrical charge, most likely as a means of self-defense or killing prey.

A modern microscope capable of magnifying images by thousands of times, which is done by firing electrons at the magnified specimen, where the resultant consequence of these electrons produces a false colour image for the microscope user to see.

A series of Redox reactions where ATP continuously gets broken down into ADP and vice versa producing a net gain of energy in the long run.

A substance consisting entirely of one element, for instance, carbon, hydrogen or oxygen. Elements can combine into compounds to form other substances.

An obstruction in a blood vessel caused by a foreign agent in the blood stream, such as a lipid molecule.

Materials responsible for causing an embolism.

The stage of development of developing offspring where they are born and able to survive in the open world.

Usually protected within a seed, the embryo in plants will remain dormant until hormones in the meristems stimulate growth.

The study of embryo's and related factors.

The membrane that protects embryo's and is responsible for supplying the embryo with nutrients from its genetic parent.

Pertaining to animals that are moving away from their natural environment into another geographical niche.

A disease which results in the breakdown of lung tissues and can be fatal over the long term.

Where the population of a species is dangerously low, so much that their gene pool diversity is adversely affected while there is a risk of the species being wiped out all together, usually a consequence from human gain.

Relating to a particular geographic area, such as the red squirrel population which is endemic to the North of Scotland.

The inner lining of the heart.

Endocrine Gland

Tissues specialised in the production of hormones which can be secreted into the bloodstream.

The collective system involved in hormone production, excretion and execution of the hormones. The hormones used by the system act as chemical messengers which allow a way of cells communicating with one another, alongside the nervous system, also capable of this.

Major organs in the endocrine system include the pituitary gland and the pancreas.

The dedicated study of endocrine glands, the endocrine system and the various factors that are involved.

A single layer of cells found in many plants, where the endodermis, consisting of endodermal cells regulate the flow of water and other materials into the plant, particularly at the roots.

An occurrence where two flowers from the same plant manage to pollinate. This is in contrast to exogamy, the mating between to distinct plants.

Pertaining to growth of an organism by internal means, i.e. the organisms genetic coding and available material.

Pertaining to the regulatory control that genes have over an organisms' internal biological activities.

An enzyme that fuses nucleic acids together.

Organisms that are usually of a parasitic nature who live on or within plants.

Interconnected flattened cavities that bear ribosomes, which host protein synthesis. Smooth endoplasmic reticulum bears no ribosomes, while rough endoplasmic reticulum (RER) bears ribosomes, due to its rough looking nature this is why it is called RER.

A type of protein produced in the nervous system that has similar effects to morphine.

A skeletal structure internal to an organism, such as the human body's skeleton.

A tissue found in many seeds which supplies nutrients to the embryo.

Pertaining to organisms which are capable of maintaining their bodily temperature above the temperature of the external environment.

Measured in joules, energy, as far as living things are concerned, is the capacity to execute a biological process. Some form of energies are heat energy, potential energy, light energy and kinetic energy.

Molecules capable of accepting energy, as in the example of the cytochrome system as part of the respiration process.

The movement of energy around an ecosystem by biotic and abiotic means. Ecological pyramids (food chains) is where a sizable percentage of energy is held, where organisms in the chain supply an energy source to other organisms and so forth, to the top of the chain which then decomposes after death.

See Pyramid of Numbers.

Entomophily

The pollination of plants by insects.

Lacking a nucleus.

The external surroundings of an organism, consisting of biotic (living) and abiotic (non-living) factors which will affect the life of all the organisms within it.

The environmental conditions of Earth are ideal for life to exist and steadily evolve within.

The resistance presented by the conditions of a species environment that stops the population of it growing out of control. A mixture of biotic factors and abiotic factors will determine how much environmental resistance is placed on an organism.

A type of protein that catalyses biological reactions. Enzymes have to operate in certain environment conditions (such as a thirty seven degree Celsius temperature in humans) to operate optimally.

There can be factors, like a change in temperature or the absence of a coenzyme that will reduce the effectiveness of an enzymes' reaction.

A type of leucocyte, that is believed to be specially adapted to deal with allergies as an immune response.

See Oestrogen.

Estrous Cycle

See Oestrous Cycle.

Ethene

See ethylene.

Ethylene is a type of hydrocarbon that can act as a plant hormone. In plants, it prevents cells from elongating and promotes leaf abscission, while sometimes being responsible for the ripening of fruit.

A Kingdom taxon that belongs under the Superkingdom Procaryota. Organisms that belong to this taxon possess cell walls and a single chromosome, and are of unicellular nature. E. coli is an example of eubacteria.

Pertaining to the euphotic zone, for instance, the term may refer to a "euphotic organism".

The area of a mass of water that is less than one hundred metres in depth, where light can still be found and photosynthesis can occur.

The term used to describe the way that natural selection gently manipulates the gene pool of a species over time so that the species is more suited to its environment and thus is more likely to survive.

The act of expelling air out of the lungs when breathing.