单词	protandrous
释义	protandrous /prəʊˈtandrəs / adjective Botany & Zoology (Of a hermaphrodite flower or animal) having the male reproductive organs come to maturity before the female. The opposite of protogynous.It is a wind-pollinated species, with hermaphroditic protandrous flowers (the first two days as male and three last days as female).... In many protandrous spiders, adult males cohabit with juvenile females nearing sexual maturity, and this may provide an index of expected mate availability for females. Perfect flowers are protandrous, hence the stigmas open after anthesis, which reduces the probability of autogamous self-pollination. Derivatives protandry noun ... Under natural photoperiodic conditions protandry in hermaphrodite disc flowers of sunflower is determined by the different elongation rates of the style and filaments. The temporal aspects of stigma receptivity and pollen longevity were investigated in relation to protandry (the occurrence of anther dehiscence prior to stigma receptivity) and breeding system. Predictions from the above hypotheses are not mutually exclusive, and associations between protandry and sexual dimorphism may be promoted by complex interactions between the suggested mechanisms acting in concert.
随便看	stanzaed stanzaic stapedial stapelia stapes staph staphylinid staphylococcal staphylococcus staple staple gun stapler star star 69 star69 star anise star apple Stara Zagora starboard starburst starch Star Chamber starcher starchily starchiness

英语词典包含243303条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。