Sexual reproduction is the obvious cause of this very important arrangement.
Especially, that form ofsexual reproduction in which an embryo undergoes a series of marked changes of external form, as the chrysalis stage, pupa stage, etc.
Defn: The production of offspring by the union of parents of different sexes; sexual reproduction; -- the opposite of agamogenesis.
In a word, sexual reproduction by multiple inheritance tends to variation of offspring, and thus furnishes material for natural selection.
All races disappear through crossing, likewise many races that have arisen from pathological variations disappear even insexual reproduction (in self-fecundation).
It is evident from this, that in reality there exists no wide chasm between sexual and non-sexual reproduction, but that both modes of reproduction are directly connected.
We must, however, try to get a very clear idea of this process and the meaning of sexual reproduction.
Sexual reproduction offers an infinite variety of interesting forms in the different classes of animals and plants, especially as regards the mode of conception, and the conveyance of the spermatozoon to the ovum.
Hence the one essential point in the process of sexual reproduction or impregnation is the formation of a new cell, the stem-cell, by the combination of two originally different cells, the female ovum and the male spermatozoon.
On the other hand, sexual reproduction is the general rule with all the higher organisms, both animal and plant; very rarely do we find asexual reproduction among them.
In sexual reproduction, with the union of ovum and sperm, we seem to have a fertile source of variation.
And in sexual reproductionwe have a constantly varying series of experiments in germinal combinations, some of which, we may fairly suppose, will be successful in giving rise to new or favourable variations.
Sexual reproduction as above, asexual by sporangia or conidia or both: Mucoraceae.
Mycelium well developed; sexual reproduction by zygospores; asexual reproduction by sporangia and conidia.
Sexual reproduction by oogonia and antheridia; asexual reproduction by zoospores or conidia.
Most of the recent work of importance in this group deals with the cytology of sexual reproduction and of spore-formation, and the effect of external conditions on the production of reproductive organs.
But before its division can begin there occurs in all cases of sexual reproduction a process called fertilization, the essential feature of which is the union of this cell with another commonly from a different individual.
The above is no merely speculative history, since all gradations between complete alternations of generations and simple budding combined with sexual reproduction can be traced in actually existing forms.
Sexual separation, which characterises the more complicated of the two kinds of sexual reproduction, has evidently been developed from the condition of hermaphroditism at a late period of the organic history of the world.
And again his work "Cross and Self Fertilisation" may be condensed to a point of view of great importance in reference to the meaning and origin of sexual reproduction.
The most important stage in the life of a flowering plant is the transition from purely vegetative growth to sexual reproduction--that is, the production of flowers.
This suggests the conclusion that quantitative internal changes in the cells, and with them disturbances in the degree of concentration, are induced, through which the chemical reactions are led in the direction of sexual reproduction.
To quote a single example; I may put the question, what internal changes produce a transition from vegetative growth to sexual reproduction?
The above list will hopefully provide you with a few useful examples demonstrating the appropriate usage of "sexual reproduction" in a variety of sentences. We hope that you will now be able to make sentences using this group of words.
