ABSTRACT
Male animals produce sperm, females produce ova (eggs), and the combination of one sperm and one egg produces a new individual. Some animals are hermaphrodites, producing both sperm and eggs, but generally, identifying male and female animals is straightforward. Higher (flowering) plants are different, and introductory botany courses provide details on the varied patterns that one encounters. An essential difference between animals and flowering plants is that adult plants do not directly produce either sperm or pollen; rather, tiny multicellular female plants are produced in the ovary of the flowers (these are parasitic, relying for sustenance on nutrients absorbed from the flower), and even tinier multicellular male plants known as pollen grains are also produced inside the flowers (in the anthers). The tiny females are stationary, awaiting visits by the mobile tiny males. The reason that flowering plants have adopted this system is that they lack a penis to introduce sperm to the eggs, or they don’t grow in a habitat where water is available in which the sperm can swim to the eggs in the ovaries. Rather, flowering plants rely on pollinators or the wind to make the transfer, and when the tiny male plants arrive at the pistil (female part of the flower), they produce a “pollen tube” (analogous to a penis), which introduces the sperms to the eggs. Only pedantic botanists concerned with technical details insist on referring to the tiny male and female plants (these are termed “gametophytes”) as the only plants that truly possess sex and insist on interpreting the large flower-producing plant as sexless (these are termed “sporophytes”).
