Question

(a) Name any two copper releasing intra-uterine devices. State two reasons that make them effective contraceptives.
(b) Name any two outbreeding devices that flowering plants have developed and explain how they help in encouraging cross-pollination.

Hint:

(a) Copper-releasing IUDs are highly effective as they not only prevent fertilization but also alter the uterine environment to reduce sperm mobility.
(b) Outbreeding devices like bright flowers and varying flowering times ensure cross-pollination, which increases genetic diversity in plants.

Answer 1

(a) Two copper-releasing intra-uterine devices (IUDs) are: 1. Copper-T 2. Multiload Cu375
These IUDs are effective contraceptives because: 1. They release copper ions, which create a hostile environment in the uterus, preventing sperm from fertilizing the egg. 2. They cause changes in the cervical mucus, making it thicker and less penetrable by sperm.
(b) Two outbreeding devices developed by flowering plants to encourage cross-pollination are: 1. Brightly colored flowers: The bright colors attract pollinators like bees, birds, and butterflies, encouraging the transfer of pollen from one flower to another. 2. Different flowering times: Plants may have different flowering periods to ensure that they do not self-pollinate, thus promoting cross-pollination when different species or individuals flower at different times.