Answer: Armored fish
Explanation:
The earliest known fossil vertebrates were heavily armored fish discovered fish in rocks from the Ordovician period.
The fossils shows the path from the early aquatic life to the vertebrates, vertebrates to mammals.
The fossils shows that it is vertebrate and are the oldest known fossil ever known. The fossils of the animals and plants helps to known the behavior of the past time and based on that research and study is done.
D is the answer to the question
A is the answer I would choose :) amos 12kvng
Answer:
Some forms of chromatin modification can be passed on to future generation of cells
Acetylation of histone tails in chromatin allows access to DNA for transcription
DNA is not transcribed when packaged tightly in a condensed form
methylation of histone tails can promote condensation of the chromatin
Explanation:
chromatin modifications that can be passed on includes epigenetic modifications that are heritable changes made to the chromatin structure that does not involve the DNA sequences. Some epigenetic modifications include DNA methylation and Histone modifications. examples of histone modification include acetylation, methylation, phosphorylation, ubiquintylation etc. All these function either in allowing the DNA become more accessible to transcritional factors or vice versa. for exmple, histone tail acetylation encourages unwounding of nucleosomes allowing transcriptional factors to have access to the DNa while histone tails methylation further tightens the nucleosomes promoting condensation of the chromatin.
The time required for a typical atom in the oceanic plate to complete the plate tectonic cycle is about in excess of two hundred fifty million years in which this is required for it to developed and to be fully complete for it to fully finish the plate tectonic cycle.