gDNA = "genomic DNA" and cDNA = "complementary DNA." cDNA is classically associated with being reverse transcribed either from all extracted RNA from a tissue or cell (total RNA) including (in eukaryotes) pre-mRNA, ribosomal RNA, tRNA, snoRNA, miRNA and mRNA, etc.) while cDNA obtained only from reverse transcription of the mRNA (expressed eukaryotic cytosolic mRNA) fraction (e.g., by poly[dT]n and random priming) is complementary DNA (cDNA) made from what is called the "transcriptome." Eukaryotes have introns and exons in the gDNA, while prokaryotes do not. So eukaryotic cDNA reverse transcribed from mRNA lacks introns. Prokaryotic-derived cDNA is always complementary to prokaryotic RNA and gDNA (so is always necessary to have a good DNase treatment prior to gene expression analysis by e.g., qPCR for prokaryotic transcriptome work)...
Diatom Cells are enclosed in a cell wall made up of silica or hydrated silicon dioxide namely frustule. The frustule has small walls where nutrients enter, enabling it to perform photosynthesis the same way plants do.
Deposition in Geography refers to a process where sediments or rocks are transported by flowing ice or water, wind or gravity. Examples include beaches, deltas, glacial moraines, sand dunes and salt domes. this phenomenon also takes place when a flood comes into contact with the plain area.
