Dense irregular connective tissue. Dense irregular connective tissue has fibers that are not arranged in parallel bundles as in dense regular connective tissue. Substances formed[edit] This tissue comprises a large portion of the dermis. This type of tissue is also in the protective white layer of the eyeball and in the deeper skin layers.
Definition of VERMICULITE. : any of various micaceous minerals that are hydrous silicates resulting usually from expansion of the granules of mica at high temperatures to give a lightweight highly water-absorbent material. See vermiculite defined for kids. ADVERTISEMENT.
Vermiculite helps hold water and fertilizer in the potting mix, and it also contains some calcium and magnesium. It has a pH near neutral. Vermiculite comes in different grades; medium grade is usually used for starting seeds, a coarse grade may be used for larger plants.tâs a good idea to test each batch of potting mix, and to be able to compare results from mixes that performed well to those that didnât. The cost is low, about $15 or $20 per SME sample. The information in this table was developed at Michigan State University in the 1980's.