Answer: The symbiotic nitrogen-fixing bacteria invade the root hairs of host plants, where they multiply and stimulate formation of root nodules, enlargements of plant cells and bacteria in intimate association. Within the nodules the bacteria convert free nitrogen to ammonia, which the host plant utilizes for its development. brainliest?
Explanation:
Answer:
The presence of organelle DNA in mitochondria and chloroplast supports the theory that mitochondria and chloroplast originated as independent prokaryotic organism.
Explanation:
- The more well documented and generally accepted theory for the origin of eukaryotic organelles is Endosymbiotic Theory. (Margulis 1970).
- Recent evidences justify that organelles have originated from the endosymbiotic association of ingested aerobic and and photosynthetic prokaryote, the precursors of mitochondria and chloroplast respectively.
- Molecular data have played an important role in supporting the xenogenous origin rather than autogenous origin of organelles.
- The idea of independent existence of mitochondria and chloroplast are: they are replicators; they carry genetic information; they have protein synthesising machinery; they have ribosome of prokaryotic type.
- The prokaryotic or bacterial origin of mitochondria and chloroplast is supported by the fact like their DNA is simple ,closed and circular with single point of origin; DNA controls the synthesis of their rRNA and tRNA etc.; They have their own ribosome; antibiotic specificity.
Answer:
B. Wind
Explanation:
Wind is the movement of air, caused by the uneven heating of the Earth by the sun and the Earth's own rotation. Winds range from light breezes to natural hazards such as hurricanes and tornadoes.
The answer is a because without them our veins would be dead
C Chromosomes break at centromeres,and sister chromatids move to opposite ends of the cell.
