SVP aider moi a :
rédiger un texte pour montrer comment l'organisme coopère pour que la production de spermatozoïdes est possible:
Hypothalamus – GnRH – Hypophyse – LH – sang – cellule de Leydig – testicules – testostérone – spermatogénèse – production de spermatozoïdes

In the practice of science, this type of reasoning is used to develop explanations.

Cladistics is a way of classifying organisms by examining the characteristics of their ancestors and descendants and depicting the relationships in a cladogram. which of the following best describes a challenge in classifying organisms this way? a. there are millions of species on earth, and a cladogram is not a practical means for classifying all of them. b. it is impossible to tell which organisms are most closely related to each other using a cladogram. c. cladograms are detail-oriented and do not provide a useful understanding of evolutionary relationships. d. there is a limited number of ways to organize the information, so most cladograms end up looking very similar.

All ova contain sex chromosomes corresponding to: x y xx xy