Blood vessels expand during hot weather and retract/ tighten in cold weather
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.
The answer is Bacteria
Prokaryotes are a microscopic single Celled organisms that has neither a distinct nucleus with a membrane nor other specialized organelles.
Plants, Dinosaurs and bugs.
