The endospores of the eukaryotes and prokaryotes are extremely important for the sake of the cells in terms of heat protection. It helps them get fully protected from harmful radiation and high temperatures which can destroy them.
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:
Birds have remarkably specialized bones that are pneumatic, because they are full of air sacs that provide a continuous flow of breath throughout their bodies. In short, their lungs are essentially hooked up to their bones.
Doesn’t normally happen until your 40’s or 50’s
