The small amount of fat in the latebra spectrum could
be due to the box being too big. The corners stick out into the yolk, which is
high in fat.
Proteins are typically only present at very low concentrations (1
millimole/liter for example). Water is very concentrated (55 moles/liter). So
the sensitivity of these spectra is just not good enough to show the
We don't know. The box is too big to tell - it covers both light
and dark rings. This would be a good experiment for a future student to repeat,
using a smaller box and placing it on each of the rings.
Fat ("lipid") is the major component of membranes. The baby chick
will be growing a lot of cells, each with a membrane around it. The lipid will
be converted into the structure of tissue. Also, the fat can be oxidized to
carbon dioxide and water to provide energy to drive the growth of the
The yolk is floating at the top of the (mostly water) albumen. Fat
is less dense than water, so it floats.