âI think weâve read every single book they have.â Mark chuckled. He still wasnât ready to put the children downâWill was hanging off of one hip, his hand on Markâs shoulder as he stoically looked down at Bridget, and Mabel had nuzzled into the crook of Markâs neck with a contented sigh.
Diatoms are producers within the food chain. A unique feature of diatom cells is that they are enclosed within a cell wall made of silica (hydrated silicon dioxide) called a frustule. These frustules show a wide diversity in form, but are usually almost bilaterally symmetrical, hence the group name.
Diatoms are microscopic algae living in both fresh and salt water. They are unicellular organisms with heavily silica impregnated cell walls. Living diatoms are amongst the most abundant forms of plankton and represent an essential part of the food chain in the ocean. Once dead, their shells accumulate on the seabed and eventually form siliceous sediment deposits.