Protections the ozone layer
Maintaining animal and human food chain
Preserving potable water and making efficient use of non renewable resources
The dichotomous key is used as a classifying tool for items in the natural world, (trees, wildflowers, mammals, reptiles, rocks...). At each step of the classification process,<span> the user is given two choices and each choice leads to another question until the item is identified.</span>
<span>A dichotomous key starts with specific information and leads to general information.
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<h3><u>Answer and Explanation;</u></h3>
- <u>Endosymbiotic theory</u> explains the origin of chloroplasts and mitochondria and their double membrane. Mitochondria of eukaryotes evolved from aerobic bacteria living within their host cell and the chloroplasts of eukaryotes evolved from endosymbiotic cyanobacteria.
- On the other hand according to the <u>autogenous hypothesis, </u>mitochondria and chloroplasts have evolved within the protoeukaryote cell by compartmentalizing plasmids or vesicles of DNA within a pinched off invagination of the cell membrane.
- <u>Endosymbiont theory </u>is the theory that suggests that simple prokaryotic cells were engulfed by larger prokaryotes 1.5 billion years ago.
- <u>Autogenous theory</u> is a theory that was proposed as an alternative to endosymbiont theory. proposes that eukaryotic organelles formed by infolding of the plasma membrane.
- <u>Horizontal gene transfer theory</u> is an alternative to endosymbiont and autogenous theories for the origin of complex organelles in eukaryotes.
The finches adapted over time to better suit their environment that they were in -- the size and shape of their beaks changed as a result of natural selection.
