Search results
Results from the WOW.Com Content Network
Plant families with epigynous flowers include orchids, asters, and evening primroses. Between these two extremes are perigynous flowers, in which a hypanthium is present, but is either free from the gynoecium (in which case it may appear to be a cup or tube surrounding the gynoecium) or connected partly to the gynoecium (with the stamens ...
The stigma, together with the style and ovary (typically called the stigma-style-ovary system) comprises the pistil, which is part of the gynoecium or female reproductive organ of a plant. The stigma itself forms the distal portion of the style, or stylodia, and is composed of stigmatic papillae , the cells of which are receptive to pollen.
In most plant species, an individual has both male and female sex organs (a hermaphrodite). [24] The life cycle of land plants involves alternation of generations between a sporophyte and a haploid gametophyte. [25] The gametophyte produces sperm or egg cells by mitosis. The sporophyte produces spores by meiosis, which in turn develop into ...
Longitudinal section of a female flower of a squash plant (courgette), showing the ovary, ovules, pistil and petals. Fruits are the mature ovary or ovaries of one or more flowers. They are found in three main anatomical categories: aggregate fruits, multiple fruits, and simple fruits.
a vegetative propagative body filled with starch (amylum) and located around the lower nodes of certain stonewort s. anastomose Branching and then rejoining, as with leaf venation. anastomosis A connection or fusion of two or more vein s that are normally diverging or branching, thereby forming a network. anatropous
It was written around 350 BC. The whole work is roughly a study in animal anatomy and physiology; it aims to provide a scientific understanding of the parts (organs, tissues, fluids, etc.) of animals and asks whether these parts were designed or arose by chance.
Combined with the five-kingdom model, this created a six-kingdom model, where the kingdom Monera is replaced by the kingdoms Bacteria and Archaea. [16] This six-kingdom model is commonly used in recent US high school biology textbooks, but has received criticism for compromising the current scientific consensus. [ 13 ]
Pollen tube elongation is an integral stage in the plant life cycle. The pollen tube acts as a conduit to transport the male gamete cells from the pollen grain—either from the stigma (in flowering plants) to the ovules at the base of the pistil or directly through ovule tissue in some gymnosperms.