Why It Matters: The Reproductive System

Why describe the components and role of the reproductive system?

Photo shows a yellow seahorse with its tail curled around a fragment of coral.

Figure 1. Female seahorses produce eggs for reproduction that are then fertilized by the male. Unlike almost all other animals, the male seahorse then gestates the young until birth. (credit: modification of work by “cliff1066″/Flickr)

Animal reproduction is necessary for the survival of a species. In the animal kingdom, there are innumerable ways that species reproduce. Asexual reproduction produces genetically identical organisms (clones), whereas in sexual reproduction, the genetic material of two individuals combines to produce offspring that are genetically different from their parents. During sexual reproduction the male gamete (sperm) may be placed inside the female’s body for internal fertilization, or the sperm and eggs may be released into the environment for external fertilization. Seahorses, like the one shown in Figure 1, provide an example of the latter. Following a mating dance, the female lays eggs in the male seahorse’s abdominal brood pouch where they are fertilized. The eggs hatch and the offspring develop in the pouch for several weeks.

Learning Outcomes

  • Describe advantages and disadvantages of asexual and sexual reproduction
  • Describe human male and female reproductive anatomies
  • Describe the roles of male and female reproductive hormones
  • Discuss internal and external methods of fertilization
  • Explain how the embryo forms from the zygote
  • Describe the process of organogenesis and vertebrate formation
  • Explain fetal development during the three trimesters of gestation