The answer to that question is c
13). Atoms are the basic unit of matter
14). Elements (pure substances, one type of atom) and Compound (made up of two or more types of atoms)
16). Chemical change
17). If a rock is changed or broken and stays where it is, it is weathering. If pieces of pebbles and soil from the rock are moved by natural forces, it is erosion
Hope that helps
<span>Repeated and prolonged episodes of stress can cause a state of exhaustion within the immune system which can ultimately cause infection.</span>
Answer:
The correct answer is spirochete and cyanobacteria
Explanation:
The endosymbiotic theory states that the eukaryotic cells are evolved from prokaryotic cells when a larger prokaryotic cell engulfed the smaller prokaryotic cell. The presence of chloroplast and mitochondria supports this theory.
After genetic analysis of chloroplast DNA, it was seen that it closely resembles the cyanobacterial DNA which shows that ancestor host cell gained photosynthetic ability from endosymbiosis with a cyanobacterial ancestor.
It was also seen that ancestral host cells engulfed spiral bacteria called spirochetes which helped them to produce cilia for example tail on sperms is the result of endosymbiosis of spirochete. So the right answer is spirochete and cyanobacteria.
