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Found Organism 631 times.

Displaying results 1 to 10.

1. Abiogenesis
Early theory that held that some organisms originated from nonliving material.

2. Abiogenic
Abiogenic refers to things not involved with or produced by living organisms.

3. Absolute filter
A fine-pored, steam-sterilizable filter that is used to trap airborne microorganisms. The filter's pores are about 2 micrometers in diameter, smaller than the particles it is designed to remove.

4. Acanthocephala (spiny-headed worms)
A phylum of parasitic organisms, from one of three general classes, generally referred to as spiny-headed worms. They are notable for their lack of a digestive tract.

5. Accessory flower parts
Sepal and petal organs found on flowers. The sepals and petals are not essential for pollination but may aid in attracting insects or other organisms.

6. Acclimatization (adaptation)
The physiological process through which an organism grows accustomed to a new environment. In microbial cultures, this can involve enzymatic changes that allow it to use an new nutrient source for energy.

7. Accumulation
Repeated exposures to a chemical may result in the progressive increase of its concentration in an organism, organ or tissue; illness or other effects may increase with successive doses. Factors involved in accumulation include selective binding of the chemical to tissue molecules, concentration of fat soluble chemicals in body fat, absent or slow metabolism of the chemical, and slow excretion of the chemical. Accumulation is a mass balance effect where input exceeds output.

8. Acellular
Describes any organism or tissue that is a mass of protoplasm which is not divided into cells, such as the plasmodium of some slime molds and the hyphae of some fungi .

9. Acetyl reduction assay (acetylene reduction assay)
A technique for measuring the nitrogen fixation activity in photosynthetic organisms. It uses a flame ionization detector and a gas chromatography apparatus to determine the reduction of acetylene to ethylene by the enzyme nitrogenase .

10. Acid-fast stain
A staining technique used to determine the cell wall property of a microorganism. After stained with dye such as hot carbol fuschin, an acid-fast organism, (.e.g. Mycobacterium species) will retain the color in its cell wall after being washed with acid-alcohol.

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