Fossils of isolated land plant spores (Heckman et al, 2001) suggest land plants may have been around as long as 475 million years ago; Fossils of land plant spores within plant fragments (Wellman et al., 2003) date back to 425 million years ago ( these were found in Oman and appear to be liverwort-like, although elaters are noticeably absent!)
The noun PUPILLARY REFLEX has 1 sense: 1. reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller. Familiarity information: PUPILLARY REFLEX used as a noun is very rare. Dictionary entry details.
A reflex is basically an automatic response, something you don't control e.g. your eyes blinking or you hands move away from a hot object. Mainly reflexes are there to prevent â¦ injuries because it's much faster than a voluntary response (actions/response you control).se of the straw is not response to stimulus, and therefore not a reflex. Reflexes follow a Reflex ARC. The Arc is through the spinal cord. While the information gets sent to the brain (you know you touched something hot, or you are choking and coughing), the reflex totally by-passes the brain.