Chlorophyll is a pigment found in the thylakoid membranes of the chloroplasts in the leaves. This is why plants are green. The simple answer is that plants are green because they have green chloroplasts.
The light-dark cycle caused by the rising and setting of the sun is responsible for what are called circadian rhythms. These are biological processes that show a cycle of around 24 hours, the time between consecutive rising of the sun. Experiments have shown that without the external cue of sunlight, the circadian rhythms of organisms tend to break down. These can be reset by being re-exposed to these cues. Jet lag is due in part to a re-setting of the circadian rhythm, as you travel to a different time zone, your body has to become used to a different timing of night and day. <span> </span>
Phloem is the food conducting tissue that has a two-way flow.
Explanation:
Plants prepare food on their own and plants also have conductive cells that carry out transportation process. Plants are divided into two types based on their conductive system i.) vascular plants ii.) non vascular plants.
Vascular plants are those plants which have special conductive cells called phloem and xylem.
Xylem transports water from roots of the plants to other parts of plants and also provides mechanical support to plant. It is uni-directional.
Phloem is the food conducting tissue that transports food to plant and also have bi-directional movement.