Why Sleeping under a tree at Night is not Advisable?

(a) At night, since photosynthesis does not occur, oxygen is not being produced by the trees. In addition to this, the trees continue respiring thereby causing the amount of carbon dioxide to be increased and the amount of oxygen to be reduced.

(b) At night, trees produce a lot of water vapour which causes the area below the tree to be very humid. This will mean that there is lesser oxygen available in the area for breathing.

(c) At night, since the stomata on a leaf are closed, there is no gas exchange taking place. Therefore, there is neither oxygen nor carbon dioxide present around a tree at night.

(d) At night, trees give out some toxic gases such as sulphur dioxide. This can be harmful to humans as well as other life forms.

Sleeping under a tree is not advisable at night, since photosynthesis does not occur, oxygen is not being produced by the trees. In addition to this, the trees continue respiring thereby causing the amount of carbon dioxide to be increased and the amount of oxygen to be reduced.

Explanation of the correct choice: Because photosynthesis does not take place at night, trees do not create oxygen.

Additionally, while the trees continue to breathe, the amount of oxygen is diminished and the amount of carbon dioxide is raised.

A justification for the incorrect choices:

Option (B):

The amount of sweating decreases at night.

As a result, the humidity below the tree is much lower than it is during the day.

Option (C):

Since they can rely on the atmosphere to interchange their breathing gases, humans do not require the exchange of gases.

Option (D):

No trees emit dangerous gases at night.