Dr. Paul's Virtually Biology Show.
An organism that obtains its energy from breaking down dead organic matter. A
decomposer is often called a saprobe. Many fungi
and bacteria are good examples.
Reasoning. Reasoning from a general concept
or theory to a specific prediction. For example, knowing the general laws of
gravity, and having mathematical equations for them, allows us to deduce or
make specific predictions about the path of a satellite.
Deme. A local
freely interbreeding group of organisms; a subpopulation.
branched part of the neuron involved in receiving chemical signals from other
neurons or information from the environment.
One of the three main tissue types in plants. This tissue occurs as a single layer
of cells on the outer surfaces of leaves and stems where it is called epidermal
tissue. Another type of dermal tissue, endodermis, separates the vascular bundle
of the root from the surrounding tissues and helps to regulate what materials
may enter the vascular system of the plant.
An organism that ingests dead organic matter(detritus) and digests this material
internally. Many small animals such as sow bugs, millipedes and worms are detritovores.
of the three natural forms of carbon. The others are graphite and buckminsterfullerine.
The period during the cardiac cycle when the ventricles are relaxed. When measuring
blood pressure if your blood pressure is 120/70, the "70" refers to
your diastolic blood pressure.
In development, refers to the increased and largely irreversible specialization
of cells as the organism develops. Recent research into cloning shows that differentiation
can be reversed artificially.
A process by which a substance moves from a region of high concentration to a
region of low concentration solely due to the thermal energy possessed by the
The breaking down of complex food stuffs into simpler compounds by means of cleavage
chromosomes in pairs of similar chromosomes called homologous chromosomes.
A mating involving pure breeding individuals with respect to alternate forms of
each of two characteristics. The offspring from this mating are then mated with
each other to examine the mode of inheritance of the two characteristics.
DNA. DNA or Deoxyribonucleic
acid is a a double stranded nucleic acid. Each strand is mad up of many units
each made from phosphate, 5 carbon sugar and one of four nitrogen containing carbon
bases. The function of DNA is to serve as genetic material in organisms and in
A complex enzyme involved in the replication of DNA.
genetics an allele that completely masks the expression of another allele at the
same locus on a homologous chromosome is said to be dominant over the second one.
A covalent bond in which each of the two atoms in the bond are sharing two electrons.
Hence the double bond involves a sharing of four electrons in all. In structural
diagrams the double bond is shown as two lines connecting the atoms.
Chromosome. A chromosome containing two identical molecules of DNA is
called a duplicated chromosome as opposed to an unduplicated chromosome which
is a chromosome with one molecule of DNA.