Sunday 20 March 2016

TEST FOR BIOLOGY STUDENTS

All living creatures and plants have a water-salt balance. If this balance is changed death may follow. We have to know that there is a movement at all times from areas of high pressure to areas of low pressure.

We put fertilizer around the base of a small plant. What happens? There is low salt pressure in the plant and high water pressure. Salt then passes from outside high to inside low. Water passed from inside high to outside low. The plant dries out and dies.

We put a fresh water fish in salt water. What happens? High water inside. Low water outside. Water passes out. High salt outside and low salt inside. Salt passes in. Fish dries up and dies.

We put a saltwater fish in fresh water. What happens? High salt inside and low salt outside. Salt passes out. Low water inside and high water outside. Water passes in. Tissues fill with water and the fish dies.

It is all because of the change of homeostasis or water-salt balance.

No comments:

Post a Comment