Silk is produced in one of three positions on the insect body: in the labium (as modified "salivary" glands),
Malpighian tubules, or in a variety of dermal glands.
To analyze the presence of sex chromatin in non-irradiated individuals,
Malpighian tubules from male and female T.
Se is shown to accumulate preferentially in the
malpighian tubules and in the midgut of insects.
In the same way, it is also the only genus in which the species produce silk from the anus using modified
Malpighian tubules (Ferriere 1941), for the spinning of the cocoon.
Associated with the digestive tract, but part of the excretory system, are the
Malpighian tubules (Figure 4).
Forms of cell death and cell survival responses which have been previously demonstrated in
Malpighian tubules of P.
Temperature-shocked larvae (positive controls) showed a maximum [beta]-galactosidase activity in all the tissues except
Malpighian tubules (Figure 2B).
However, when the characters that have been used to connect the insects and the myriapods were reviewed, the results suggested that they are either suspected of being convergent (i.e.,
Malpighian tubules, tracheae) or are not significant in a phylogenetic discussion (loss or absence of characters) (1, 2).
Testes length (TL), testes area (TA),
malpighian tubules length (MTL), and
malpighian tubules area (MTA) were measured as shown in Figure 1.
Giebultowicz of Oregon State University in Corvallis and her colleagues have found biological clocks in the testes of moths and in the fruit fly's
Malpighian tubules, excretory organs similar to kidneys.