The number of cycles per second (Hertz) (abbreviated as, hz) of anything that oscillates is called the frequency. The electricity of an AC wall outlet is said to have a frequency of 60 Hertz as it cycles negative then positive 60 times each second. Sound is an oscillating wave, but it has a broad range of frequencies. A low frequency sound (say, 50 hz) might sound like a low rumble, while a high frequency sound (say 12,000 hz), might sound more like a sizzle. A person with normal hearing can hear all the way up to about 20,000 hz.
The noun SECRETORY PHASE has 1 sense: 1. the second half of the menstrual cycle after ovulation; the corpus luteum secretes progesterone which prepares the endometrium for the implantation of an embryo; if fertilization does not occur then menstrual flow begins Familiarity information: SECRETORY PHASE used as a noun is very rare.
Definition. noun, plural: secretions. (1) The physiological process of synthesizing and eventually releasing substances from the interior of a cell to its exterior. (2) The substance secreted. Supplement. In eukaryotes, cells primarily involved in secretion have well-developed endoplasmic reticulum and Golgi apparatus.n prokaryotes, such as bacteria, secretion occurs by releasing substances from the bacterial cell interior to its external environment. Word origin: Latin secretio, from secernere (to secrete). Compare: 1  excretion.