Dictionary, Defintion, Meaning, What is Acrogenes, Active Transport, Acrania, Acrasiales, Acrogyny, Acromion, Acropetal, Acrosome, Actinomorphic, Actinomycete, Actinomycin

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Biology Dictionary Biology Dictionary - Part 1 Part 2 A band Abomasum Accentric Chromosome - Acetylcholinesterase Acrogenes - Active Transport Adaptive Enzyme - Adrenegic Aggulutination - Alimentary Canal Allantois - ALS Anti Lymphocytic Serum Amitosis - Amphibia Amylases - Angiospermae Annelida - Antagonism Antibiotic - Antigibberllins Aphid - Apospory Arachnida - Arteriole Artificial Parthenogenesis - Asteroidea Atrium - Autecology Autosome - Avitaminosis Bacillariophyta - Baer's Law Barrington's Reflex - Basidium Biennial - Bio Assay Bioluminescence - Blastocyst Blood Clotting - Blood Corpuscle Blood Plasma - Bolus Bracteole - Bryophyta Bulbil - Caenogenetic Cambium - Capsule

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Your Ad Here	Acrania An outdated taxonomic term often used as a synomym of protochordate but in some classification limited to synonymy with cephalo chordate. Acrasiales A grouping in some classification within the myxomyceta which includes those slime moulds that are cellular or communal and which do not coalesce. Acrogenes Ferns and mosses.
Acropetal (Bot). Development of organs in succession towards apex, the oldest at base, youngest at tip, e.g. leaves on a shoot. Also used in reference to direction of transport of substances within a plant, i.e. towards the apex. Acrosome Part of head of animal sperm, usually forming a cap over the nucleus. It contains enzymes concerned in penetration of the egg covering and perhaps fusion with the egg during fertilization. ACTH (Corticotriopin). Adreno-cortico-tropic hormone, produced by anterior lobe of pituitary, controlling the growth and secretory activity of adrenal cortex.
Actin Protein that, in conjunction with myosin (q.v.), provides the contractile mechanism in muscles, and in other cells. Actinomorphic (Of flowers), capable of bisection vertically in two or more planes into similar halves, e.g. butter cup. Actinomycete A group of gram-positive bacteria (Actinomycotales) with cells arranged in hypha – like filaments. Mostly saprophytes, some parasites and source of streptomycin. Actinomycin. Antibiotic that combines with DNA, thus preventing transcription. Actinosphaerium A protozoan known as the sun animalcule, which is related to Amoeba.	Your Ad Here
Actinozoa (Anthozoa) Sea anemones, corals, sea pens, etc. These animals are usually colonial though sea-anemones and some others are solitary, sedentary (fixed), with tentacles around mouth, gastro-vascular cavity partitioned with septa or mesentries. All actinozoans are not corals (e.g. sea-anemones like Metridium, Adamsia) and all corals are not actinozoans (e.g. stinging or fire coral is millepora belonging to anoterh class Hydrozoa of the same phylum). Most actinozoan corals are colonial and contribute to the formation of coral reefs along with many other animals and plants. Acrogyny Said of the gametophyte of some Bryophyta, when growth stops on the formation of archegonia. The apical cell forming the last archegonium. Acromion Point of the shoulder girdle. The spine of the scapula terminates in the acromion process.
Your Ad Here	Action potential Of a nerve impulse; a localized change of electrical potential between the inside and outside of a never fibre, which marks the position of an impulse as it travels along the fibre. Action Spectrum A graphical plot of efficiency of electromagnetic radiation in promoting or inhibiting a particular reaction, e.g. action spectra for photosynthesis, show maximum absorption and activity in blue and red parts of visible spectrum. Activated sludge Any material used in sewage treatment, consisting mainly of bacteria and protozoans, the purifies the sewage and increase by multiplication during the process. Part of the new sludge is used in the continuing treatment of the sewage.

Active center
The site or surface an enzyme molecule that combines with the substrate. A relatively small number of the atoms of the enzyme molecule is involved.

Active transport
The movement of substance from region where its concentration is low to where it is high, especially through a membrane; accomplished by means of expenditure of energy from metabolism.

Activity
The ability of a substance to react with another.

Actomyosin
Complex of two proteins, action and myosin forming a major constituent of muscles.

Acuity
Sharpness of vision; the resolving power of the eye.

Adaptation
(1) Evolutionary
Any change in the structure of organisms which, in the environment they inhabit, improves their changes of survival and ultimately of leaving descendants. An adaptation to a particular feature of the environment means a characteristic which is an adaptation because it reduces destruction by the particular feature.
(2) Physiological a change in an organism as a result of exposure to certain environmental conditions which makes it react more effectively to these conditions.
(3) Sensory a change in excitability of a sense-organ as a result of continuous stimulation such that a more intense stimulus becomes necessary to produce the same response.

Activator
Any drug that increases the activity level of the person being treated.

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Biology Dictionary - Part 3 Part 4 Cardinal Veins - Carotenoid Cartilage Bone(Replacing Bone) - Cataract Cell Body - Cell Mediated Immunity Centipide - Centriole Centrum - Cerebrospinal Fluid Chalaza - Chemotaxis Chloroplast - Chorda Mesoderm Chromatid - Chromosome Ciliary Feeding - Circadian Rhythm Cleidoic Egg - Clotting Factors Cobalamine - Coenzyme Collagen - Columella Auris Compensatory Hypertrophy - Compound Eye Coinferales - Connective Tissue Cork Phellem - Corpus Luteum Cranial Nerves - Cycadales Cymose - Cytotaxonomy

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