The R group should have the ability to form hydrogen bonds.
The R-group take a lot of different chemical forms and can
be acidic, basic, polar or non polar. Amino acids that are either acidic or basic
consequently have either positive or negative charge. These types of R-groups
are stabilized when surrounded by water.
It's letter A - Obligate anaerobe.
<em>Obligate anaerobes</em> are microorganisms killed by normal atmospheric concentrations of oxygen. A <em>facultative anaerobe</em> prefers to produce energy in the presence of oxygen but can survive without it. <span>A <em>photoautotroph </em>is an organism that converts light energy into chemical energy. </span><span>Prokaryotes may perform </span>aerobic<span> (oxygen-requiring) or </span>anaerobic<span> (non-oxygen-based) metabolism and some can switch between these modes. Since we're talking about an environment without oxygen and dies when exposed to oxygen, the preferable answer is A.</span>
Answer:
The right answer to this question is option A) island forms and mainland forms descended from common ancestors.
It's known in science that a long time ago, all the continents were only one, united all together in a bigger one. This can be observed by the way every continent can fit another one.
A proof of that too, is evolution, when we find organisms in an island that share some characteristics with organisms from another island, that can mean some things, they come from the same place, or these islands share characteristics that lead these organisms to be this way through evolution.
