Pyroclastic rocks are the product of explosive volcanism. They are often felsic (high in silica). Pyroclastic rocks are often the result of volcanic debris, such as ash, bombs and tephra, and other volcanic ejecta.henocrysts are crystals that are larger than the matrix and are identifiable with the unaided eye. Rhomb porphyry is an example with large rhomb shaped phenocrysts embedded in a very fine grained matrix. Volcanic rocks often have a vesicular texture caused by voids left by volatiles trapped in the molten lava.
July 9, 2014. Frozen sperm must be stored in extremely cold temperatures (-196 F), but in order to ensure that the fewest possible sperm are damaged, the freezing must be gradual. Generally, the following procedure is followed:
In order for the testicles to properly produce sperm, the organs must be kept 1 to 4 degrees cooler than the body. To keep the testicles in the proper temperature range, the scrotum constantly changes size. If the temperature is too cool, the scrotum contracts, bringing the testicles closer to warmth of the body.he epididymis is a soft area on the upper-back portion of each testicle. The testicles in the average healthy male produce about 100 million sperm cells per day. Each ejaculation contains about 500 million active sperm cells in a healthy man.