Components of the 19 critical
subsytems of a cell
[note: based on science as per 1979]
Subsystems which
process both matter-energy and information
Reproducer: chromosomes and chromatin in nucleus; ribosome,
mitochondrion, kinetosome, chloroplast;
centrosome, aster,
centriole, and spindle in cytoplasm
Boundary: for
matter-energy, cell membrane plus cell wall or other protective
structures;
for information, cell membrane including specialized
areas at synapse and neuromyal junction
Subsystems which process
matter-energy
Ingestor: cell
membrane as a whole or specialized regions such as peristome,
cytostome, gullet;
tentacles to hold food and cilia to sweep it
in
Distributor: endoplasmic reticulum, sarcoplasmic
reticulum of muscle cells;
ground substance, including axoplasm
of neurons; microtubules, microfilaments
Converter: enzymes
such as those in mitochondrion, cell membrane, chloroplast, nucleus,
or lysosome;
vacuoles which carry out phagocytosis or
pinocytosis
Producer: chlorophyll, chloroplast; enzymes
such as those in mitochondrion;
Golgi apparatus; nucleic acids of
nucleus and ribosome
Matter-energy storage: Phosphorylated
organic compounds (e.g. ATP, creatine phosphate, and argenine
phosphate of muscle cells); starch or glycogen granule; glucose,
fructose, lactose; lipochondrion; lipid, including fat droplet; some
protein; secretory granule
Extruder: region of cell
membrane capable of matter-energy transport out of cell, including
anal pore or cytoproct and vacuole of protozoan; excretory canal of
some glandular cells; possibly sarcoplasmic reticulum
Motor:
cytoplasm, the microtubules and microfilaments of which enable it to
move, as in a pseudopodium;
cilium; flagellum;
myofibril
Supporter: microtubules, microfilaments;
myofibrils of muscle cells; cell walls of plant cells; cell membrane;
wall of cysts
[note: structures that
associate cells with each other are not mentioned here]
Subsystems which
process information
[Can you see the parallel with subsystems
that process energy-matter?]
Input transducer
[sensor]: cell membrane; particularly specialized receptor sites
of cell membrane, including subsynaptic region of neurons, muscle
fibers, glandular cells; light-sensitive pigments, cilia, other
specialized parts of receptor cells
Internal transducer:
enzymes and repressor molecules
Channel and Net:
endoplasmic reticulum, sarcoplasmic reticulum of muscle cells;
ground substance, including axoplasm of neurons; microtubules,
microfilaments;
cell membrane, transverse system of muscle cells,
nuclear membrane
Decoder: molecular binding sites, such as
the operator, a ribosomal molecule, or subsynaptic membrane;
parts
of cell membrane, such as postsynaptic membrane or membrane of
initial segment of axon
Associator: unknown [question: can
a plant-cell learn? Answer: why not? A plant as a whole displays
remarkably sophisticated behaviour in the defense against hostile
insects; it can secrete specific substances that deter such insects.
This may apply more to the plant as an organism than an individual
plant cell. Nice research project for biologists.]
Memory:
unknown
[note: it seems likely that cells have some memory system;
certainly organs seem to carry the impressions of the habits of the
person to whom' s body the organ belongs. This is sometimes
noticeable in cases of organ transplants! Unexpected changes in
habits may occur in the person receiving the donor-organ. Such cases
are certainly known and published in at least one book I know.
]
Decider: regulator genes and operon, including structural
genes, and perhaps architectural and temporal genes in nucleus;
possibly operator, promotor, activator RNA, repressor sites,
replicon, initiator, replicator, effector or modifier or modulator
components; cytoplasmic DNA; parts of cell membrane, as of axon
hillock, initial segment of axon, first node of Ranvier, other
specialized cell membrane sites of neurons; other components.
[note:
timer structures are not mentioned here]
Encoder: components
producing alpha-coded antigenic proteins, hormones, and other
molecules output as signals by cells; component producing transmitter
substance output by neurons, perhaps mitochondrion or synaptic
vesicle; part of electroplaque cell that produces electric pulses;
part of cell membrane that determines axon pulses, perhaps near
initial segment of axon
Output transducer: cell membrane;
presynaptic membrane and neuromyal junction; prejunctional region of
neuron; synaptic vesicle