The effects of GnRH on the secretion of LH and FSH are not exactly parallel, and the variations are probably due to other modulating factors such as the serum concentrations of steroid hormones (substances secreted by the adrenal cortex, testes, and ovaries).
The noun OBSTACLE has 2 senses: 1. something immaterial that stands in the way and must be circumvented or surmounted. 2. an obstruction that stands in the way (and must be removed or surmounted or circumvented). Familiarity information: OBSTACLE used as a noun is rare.Dictionary entry details.. something immaterial that stands in the way and must be circumvented or surmounted. 2. an obstruction that stands in the way (and must be removed or surmounted or circumvented). Familiarity information: OBSTACLE used as a noun is rare.
(often foll by up) to obstruct (a passage, channel, etc) or prevent or impede the motion or flow of (something or someone) by introducing an obstacle: to block the traffic, to block up a pipe 35. to impede, retard, or prevent (an action, procedure, etc)