False. The opportunity of a new job or house you have wanted can cause stress as well. Stress is an emotion just like crying over extreme happiness or sadness
ANSWER: Nitrogen, oxygen or gas, dust particles
Answer:
The cell membranes controls what goes in and out by having protein channels that perform their role accordingly sometimes like funnels and like a pump in different cases.
When a channel open in the plasma membrane it allows molecule to pass through, in this case there is no requirement for energy so it is a passive transport.
Gases and food particles broke down in water must be assimilated and waste or harmful substance and molecules must be remove. For most cells, this type of selective transport of all materials all through the cell must happen through the plasma membrane.
Answer :
Vinegar is a weak acid. This is used to make a naked egg. When an egg is added in the vinegar for one day / 24 hrs, it reacts with the eggshell. The calcium carbonate shell gets dissolve.
Then an egg without shell is formed and the size of the egg does not change. The calcium carbonate reacts with acetic acid and forms carbon dioxide.
When the shell-less egg is kept in the vinegar for 48 hrs i.e. 2 days again, the water content in it enters into the eggs through the membrane. Then the egg gets somewhat bigger.
Otherwise, for 24 hrs, vinegar is acting like an isotonic solution and only dissolves the shell. This experiment would be done for showing the osmosis process through the cell membrane.
