Chapter 24, Problem 8A

Summary Introduction

To write:The advantages and disadvantages of internal and external fertilization

Introduction:Fertilization takes place as the sperm penetrates into the egg to create a fertilized egg cell known as zygote.Sexual fertilization is the fusion of the female egg cell with a male sperm in the female body, during sexual reproduction. With the assistance of an intromitent organ, sperm is transferred from the male into the uterus. External fertilization is the process in which the male and female gametes are combined outside of the mother's body.

Explanation of Solution

• Advantages of internal fertilization

There are some benefits of internal fertilization. The female reproductive tract offers a small and protected location where sperm and egg will interact, without the possibility of being swallowed by predators or swept away by water currents. The zygote may accumulate secretions, membranes, or shells for the protection of the developing embryo when traveling down the female reproductive tract.

• Disadvantages of internal fertilization

Lower numbers of offspring are produced at a given time. The explanation for this is that the male and female often have trouble coming into close contact. Besides that, there is an growing chance of sexually transmitted infections.

• Advantages of external fertilization

It results in greater variations in the genome. This requires a greater number of offsprings. The gametes produced can drift and thus, mates can be easily identified.

• Disadvantages of external fertilization

The plenty of gametes are lost and left unfertilized. Environmental threats and Predators reduce the chances of fertilization. Basically, eggs and sperms cannot come into contact. Zygote or gametes are desiccated

Conclusion

Thus, it concludes that internal fertilization occurs in mammals, reptiles, birds and other species of the marine. On the other hand, frogs, starfish, and salmon are the most common examples of species that conduct external fertilization.