Time for a plant rant! Hooray!
Please note that explanations on this blog are generally at the curious 10-year-old level; not for the expert or specialist. Please alert me to errors within that context.
The flowers of most flowering plants have both male and female parts on the same flower; these flowers are called perfect. Some flowering plants have separate male and female flowers on the same plant; these plants are called monoecious. (e.g., Arizona Black Walnut Juglans major, Mexican Blue Oak Quercus oblongifolia).
A few flowering plants have separate male and female plants. These plants are called dioecious. Let's look at one example that's blooming now, namely: Jojoba (Simmondsia chinensis).
|Photos by Matt Ball 2/7/2015|
This is the male plant. These flowers produce pollen; pollen is the plant equivalent of sperm in the animal world. There's always a lot more pollen than eggs!
This is a close-up of a female flower (on a female Jojoba plant : -) As in the animal world, the female has the egg(s)! If this female flower is pollinated (the egg is fertilized), the embryo will develop into the seed (which is contained in the fruit). The seed is the (potential) next generation.
Other dioecious plants include Desert Broom (Baccharis sarothroides) and Fourwing Saltbush (Atriplex canescens).
Further reading for the plant curious.