Re: Do all plants have chloroplasts?

1. Underground plant parts, such as most roots and underground stems would
generally lack chloroplasts because they are in the dark. Nongreen flower petals
probably lack chlorophyll as do internal cells in the stem, seeds and fruits. 
Epidermal cells usually lack chloroplasts except for the guard cells of the
stomata. 

Parts of plants that are not green may or may not have chloroplasts. Many
nongreen leaves have chlorophyll, e.g. purpleleaf plum, blue Colorado spruce and
red Japanese maple. In nongreen leaves, other pigments may mask the green
chlorophyll. Some barks have chloroplasts even if they do not appear green. It
is often possible to scratch off the bark on nongreen twigs and expose green tissue.

2. If a plant lacks chloroplasts, it also lacks chlorophyll and vice versa.
Parasitic plants that are pale yellow or white will lack chloroplasts, e.g.
dodder. Myco-heterotrophic plants also lack chloroplasts, e.g. Indian pipes and
Rafflesia. Albino plants also lack chloroplasts due to a mutation. Plants
growing in the dark for an extended period of time usually lack chloroplasts too.

3. Leaves turn color in the autumn for a couple of reasons. If the leaves turn
yellow, it is because the chlorophyll is being degraded and the yellow
carotenoids that have been there all season are revealed. Leaves that turn red
are synthesizing anthocyanins that supposedly act as a sunscreen to protect the
plant.

References


Re: Do all plant cells contain chloroplasts?


Re: Are the green parts of plants the only structures that produce oxygen?


Re: why do plants produce more anthocyanins when stressed for nitrogen.


Foote, K.C. and Schaedle, M. 1976. Physiological characteristics of
photosynthesis and respiration in stems of Populus tremuloides Michx. Plant
Physiology 1976 58: 91–94.