Reproductive Biology (Part-III)

Introduction: So afr we have discussed different asexual methods in bacteria, fungi and lower plants. Now in the current lecture, we will discuss different steps of sexual reproduction with suitable examples. The major steps of sexual reproduction is given in the Figure 20.1.

Figure 20.1: An Over-view of different steps in sexual reproduction.

Step 1: Organism produces male and female gametes.
Step 2: These gametes are fused to form zygote.
Step 3: Zygote develop into new organism.
But miute details of these steps are not identical in every organism. In the current lecture, we will focus more on the generalized events rather than any specific organism.

Sexuality is organisms: The male and female parents are separated in many organisms and these are said to be unisexual or dioecious. The different between human male and female sex character is given in Table 20.1. In few animals both sex organs are present in the same animal. These are considered as bisexual or hermaphrodite For ex. Earthworm, liverfluke, leech. Bisexuality facilitates the efficiency of fertilization and higher yield of eggs. It also facilitates self pollination in plants as well.