<span>there is no easy definition of an algae. Algae are generally microscopic organisms, are usually thought of as simple aquatic plants which do not have roots, stems or leaves and have primitive methods of reproduction. </span>
Answer;
Semi-permeability means that only certain molecules are allowed to pass through.
Explanation;
-Semi-permeability is one of the features of a cell membrane, which means that the membrane allows selective movement of materials in and out of the cell; that is only certain molecules can enter or leave the cell.
-For example smaller molecules such water and ions such as potassium and sodium ions are able to leave and enter the cell, while other molecules that are large such as protein molecules can not enter or leave the cell.
The concept would be crystallization. As magma cools inside or outside of the earth it crystallizes into an igneous rock. Intrusive (formed inside crust) igneous rocks are typically more course grained and contain many different noticeable minerals (for example, granite). Extrusive (formed outside) igneous rocks are typically more porous and are more fine grained then intrusive rocks (example, obsidian).
Technology such as lenses, magnifying glasses, and microscopes had an impact on the development of the cell theory. Below are some examples of how such technologies contributed to the cell theory. Robert Hooke is accredited with observing the first cells in 1665. ... He used lenses to make the discovery.
