It’s the last one.
All of these are parts of the cell theory.
The right answer is A.) DNA in mitochondria
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Eukaryotic cells, with their many intracellular organelles, have long been considered progeny of prokaryotes that would have become more complex as a result of genetic mutations. But from the 1960s, biologist Lynn Margulis proposed an alternative explanation that was first received coldly by the scientific community. His endosymbiotic theory, proposed in a more formal way in a 1981 book, proposes that eukaryotic cells as we know them today would be the result of a series of symbiotic associations with different prokaryotes.
Mitochondria and chloroplasts also have their own DNA that is not trapped in a nucleus, which is also the case with prokaryotes. However, the proteins encoded by this DNA do not cover all mitochondrial proteins. The prokaryote is thought to have lost some genes to the nucleus of the cell, a process known as "endosymbiotic gene transfer". For this reason, mitochondria and chloroplasts are now host-dependent for the synthesis of most of their components.
Compare the limbs of different organisms goes in left box. compares fossilized structures to living organisms left box.
other 2 go in the right box hope this helped(:
Answer:
b. 8P+ , 10no , 8e-
Explanation:
An isotope is a form of a chemical element whose atomic nucleus of an element contains a specific number of neutrons and protons. For example, the nucleus of a carbon atom contains 6 neutrons(no) and 6 protons(P+) and similarly in the nucleus of oxygen contains 8 neutrons and 8 protons . The number of neutron can varies in the nucleus of that element. Variation in neutrons form isotopes of the element. In nature, oxygen has three stable isotopes, ¹⁶O, ¹⁷O, and ¹⁸O, but ¹⁶O most abundant. The ¹⁸O isotope of oxygen contains 8 protons(P+), 8 electrons(e-) and 10 neutrons(no) instead of normal 8 neutrons.
Answer:
Antigen-presenting cells show digested antigens to T cells through the MHC on their surface, which allows the T cell to “see” the antigen and recognize it as foreign. The connection between the MHC and the receptor on the T cell is the first signal necessary to activate the T cell to respond to a tumor and destroy it.
Explanation: