JAMB - Biology (2001 - No. 12)
The structure that holds the yolk in position is labelled
II
I
IV
III
Vysvětlení
I - Albumin
II - Shell
III - Chalaza
IV - Germinal disc
The chalazae are a pair of spring-like structures that project from the equatorial region of the vitelline membrane into the albumen and are considered to act as balancers, maintaining the yolk in a steady position in the laid egg.