Silkmoth Chorion: A Natural Protective Amyloid - The Functional Fold: Amyloid Structures in Nature - page 57

a b

Figure 4.1 (a) Two ovarioles dissected from a developing adult female

Bombyx mori are each

composed of four ovarioles. Follicles in progressively advanced
stages of development (0, 1, 2, …, 22) are interconnected
in a linear array within each ovariole; 0 follicle indicates
the beginning of choriogenesis (Papanicolaou

moth. The paired ovaries in B. mori

1986).
Bar = 3 mm. Copyright 2008 NRC Canada or its licensors.
Reproduced with permission. (b) Schematic diagram of a
follicle. FC, follicle cells; OC, oocyte. The eggshell consists of
chorion (CH) and vitelline membrane (VM).

et al.

Figure 4.2 Transmission electron micrograph of a thin section cut

through a chorion of silkmoth. Within

the bulk of the lamellar chorion, four types of lamellae can
be distinguished: thin lamellae of the inner lamellar layer
(IL); thick, distorted, spongy lamellae of the holey layer (HL);
lamellae of the outer layer (OL); and, lying at an angle to the
rest, the thick lamellae of the oblique layer (OB). Nearest to
the oocyte is the trabecular (TL) layer, which consists of
pillars surrounding air-filled spaces (Hamodrakas

Abtheraea polyphemus

et al. 1986).

Bar = 10 μm.