REFERENCE SECTION: BIOLOGICAL TERMS
Complete the Table below, which defines or describes some important
biological terms that are occasionally included in chemistry texts, by
inserting the correct word from this list: Active transport; Allele; 
Autotroph; Cell; Diffusion; Codominance; Dominant allele; Enzyme; 
Excretion; Food chain; Gene; Genotype; Growth; Herbivores & Carnivores; 
Heterotroph; Heterozygous; Homeostasis; Homozygous; Irritability; 
Limiting factor; Movement; Nutrition; Organism; Osmosis; Phenotype; 
Population; Recessive allele; Reproduction; Respiration; Saprotrophs; 
Sex-linked allele; Species; Trophic level.
     Term     
             Definition or Description
 
 A structure containing the genetic code for
 reproduction.
 
 A group of organisms capable of breeding to produce
 fertile offspring; e.g., Ursos arctos (brown bear).
 
 A group of individuals in a species that live in a
 defined habitat.
 
 An assembly of fragile molecules, enclosed within a
 semi-permeable membrane, which show some or all the
 other characteristics of living things.  *
 
 The maintenance of a constant internal environment
 despite changes in the external environment.
 
 The removal of waste products of cellular metabolism. 
 
 The change in position of whole or part of a living
 organism.
 
 
 The enzyme-controlled release of energy, in the form
 of ATP, by the oxidation of organic compounds.
 
 The formation of new organisms to ensure the survival
 of the species.
 
 The ability to detect and respond to changes in the
 external environment.
 
 The processes by which chemical energy is obtained
 and assimilated.
 
 The irreversible increase in dry mass of an organism
 via biosynthesis and mitotic cell division.
 
 A catalytic protein.
 
 The net movement of particles down the concentration
 gradient; i.e., from high to low concentration.
 
 The net movement of solute particles, across a
 semi-permeable membrane, against the concentration
 gradient; i.e., from low to high concentration.
 
 
 The net movement of water particles, across a semi-
 permeable membrane, down the concentration gradient; 
 i.e., from high  to low concentration.

     Term     
             Definition or Description
 
 An organism which biosynthesizes its chemical energy
 from inorganic compounds.
 
 An organism which obtains its chemical energy from
 the organic compounds produced by other organisms.
 
 Ingestive heterotrophs which obtain their chemical
 energy from living organisms.
 
 Absorptive heterotrophs which obtain their chemical
 energy from dead organisms and their excretions.
 
 A series of organisms through which chemical energy
 is transferred by feeding.  #
 
 The position of an organism in a food pyramid.
 
 Any variable which reduces the rate of a biological
 process from its possible maximum.
 
 
 The basic unit of inheritance; in molecular terms,
 it is the sequence of DNA nucleotides which codes for 
 the synthesis of one polypeptide.  $
 
 One of a number of alternative forms of a gene.
 
 The allele(s) present for a specific characteristic.
 
 The physical or chemical expression of the genotype.
 
 One allele of a pair which has an effect on the
 phenotype when homozygous or heterozygous. (Shown in
 a genetic diagram by a capital letter; e.g., H.)
 
 One allele of a pair which has an effect on the
 phenotype when homozygous. (Shown in a genetic 
 diagram by a small letter; e.g., h.)
 
 When both alleles in a heterozygous individual are
 expressed in the organism's phenotype.
 
 An alternative form of a gene which is carried on a
 sex chromsome.
 
 
 Where two alleles for a characteristic are the same
 (e.g., HH or hh).
 
 
 Where two alleles for a characteristic are different
 (e.g., Hh).
                                                                   [33]
*  Most living organisms usually show nine characteristics; i.e.,
cellular organisation, homeostasis, excretion, movement, respiration, 
reproduction, irritability, nutrition, and growth. (... 'Chemrring' ?).
[Viruses, which are invariably parasitic and pathogenic, are viewed as
non-living organisms because they do not show these characteristics.]
#  A similar transfer occurs in a food web, but involves interacting
organisms (i.e., communities).
§  Despite their surprisingly frequent appearances, the terms 'dominant 
gene' and 'recessive gene' are both incorrect.

Dr. R. Peters                   Next                     Contents' List