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:
The question lacks options, the options are:
A. moisture content of seed must be at least 9%
B. Moisture content of the seed must be less than 9%
C. certain enzymes in the seed are activated
D. temperature must be above 80 degrees
E. temperature must be below 80 degrees
The answer is A
Explanation:
Germination is practically the very first step of every seed-producing plant. It is the process whereby seeds sprout or begin to grow. Germination requires certain conditions to be met in order to occur. This conditions include presence of moisture in the soil etc.
The water is absorbed by the seed helps to soften the seed coat, which protects the seed from damage. The seed coat ruptures, causing the emergence of growth structures from the seed. In general, seeds need water to activate their dormant physiology. Hence, the moisture content of the seed must not be lower than 9%.
A sedimentary rock is bits of broken up rock
