Answer:
Mold fossils A fossilized impression made in the substrate; a negative image of the organism.
Cast fossils Formed when a mold is filled in.
Trace fossils or Ichnofossils Fossilized nests, gastroliths, burrows, footprints, etc.
True form fossils Fossils of the actual animal or animal part.
The question is incomplete as it does not have the options which are:
- there was no sulfur compound added to the medium, that could be used as an electron donor.
- no oxygen was added to the medium so the organism died.
- there is some inhibitory chemical that is preventing the growth of the bacterium.
- you were using the wrong type of sunlight as the energy source for the bacterium.
Answer:
There was no sulfur compound added to the medium, that could be used as an electron donor.
Explanation:
In the given question, the bacteria which are found in the pond uses light energy to use carbon dioxide and form the glucose molecule. These bacteria are known as phototrophic bacteria.
The process of photosynthesis requires an electron donor and an electron acceptor to use molecule.
The organism when provided the light and carbon dioxide artificially in a culture, the bacteria were not able to grow. The reason for this could be accounted as that there was no electron donor found in the media like sulfur which could donate the electron during the chain reaction.
Thus, the selected option is correct.
Answer:
Chromatin
Explanation:
The unwound, filamented mass of DNA and associated proteins in a cell that is not dividing id termed as 'chromatin'. The major function of the chromatin is to pack the DNA into the compacted dense shape so that any type of tangling is avoided in the DNA strands. The chromatin is known to be present in every eukaryotic cell. It is due to chromatin that the chromosomes are properly segregated during the anaphase. The nucleus is the site where chromatin is present.