Parts of the Reproductive System of Fish and their Functions

Subject : 

Biology

Topic :

Control of Diseases Caused by Pests

Term :

Second Term

Week:

Week 6

Class :

SSS 2

Previous lesson : 

The pupils have the previous knowledge of

Management And Control of Pests

that was taught in the last lesson

Behavioural objectives :

At the end of the lesson, the pupils should be able to

• define pest control
• say the methods of pest controls
• list the diseases cause by pests and their agents

Instructional Materials :

• Poster
• Wall Chart
• News paper
• Online Video
• Pictures

Methods of Teaching :

• Class Discussion
• Group Dialogue
• Asking Questions
• Explanation
• Role Modelling
• Role Delegation

Reference Materials :

• Scheme of Work
• Online Information
• Textbooks
• Workbooks
• 9 Year Basic Education Curriculum
• Workbooks

Content :

Control of Diseases Caused by Pests

Control of diseases caused by pests involves:

1. Physical methods: this involves removal of diseased plants. Weed hosts are also removed. Bush burning and soil flooding are other methods.
2. Cultural methods: this involves the modification of farming practices to destroy disease-causing agents. Early planting and use of balanced fertilizers enable plants to be well established before the peak period of infection. Planting resistant varieties also help control diseases.
3. Chemical methods: this involves the use of chemical agents to either eradicate the crops from such agents. These are best methods of diseases control.
4. Integrated method: this involves the combination of two or more methods highlighted above, for effective disease control.

Other methods are:

1. Prevention of crops from being infected by disease-causing agents.
2. Destruction of disease-causing agents and their respective vectors.
3. Prevention of disease plants or animals from entering into country by government.
4. Distribution disease-free planting materials.

REPRODUCTIVE SYSTEMS IN FISH AND REPTILES

CONTENT

A. Reproductive Systems in Fish and Reptiles

1. Structures of the Male and Female Reproductive Systems
2. Parts of the Reproductive Systems and their Functions
3. Structures of the Male and Female Gametes (Sperm and Ovum)
4. Differences between Male and Female Reproductive Organs

Structures of the Male and Female Reproductive Systems of Fish and Reptiles

The reproductive system plays a vital role in the reproduction of organisms. Vertebrates like the fish and reptile have distinctive systems that are involved in the process of their reproductive reproduction.

Structures of the Male and Female Reproductive System of Fish

In bony fishes like tilapia, the male reproductive system is made up of two elongated testes which are surrounded from the stomach. The testes be a part of a easy duct which opens at a genital opening often known as Cloaca. Within the females, the ovaries are contained in sac-like constructions also suspended from the abdomen. The ovaries are related in a easy duct which results in the genital opening.

Generalized Anatomy of a Fish

Each the digestive and circulatory methods in most fishes are quite easy. Though a number of species can breathe atmospheric air, most fish breathe via gills. The swim (or fuel) bladder permits fish to take care of a continuing buoyancy whatever the altering water stress at various depths.

In cartilaginous fish like shark the male reproductive system consists of the testes, vasa efferentia, vas deferens urino genital papilla, clasper and different inclusion that improve replica. The testes are lengthy cylindrical organs. The feminine reproductive system is made up of two ovaries.

Shark Egg Case with Embryos

These two dogfish egg cases show the developing embryos inside. Each egg case contains enough yolk to sustain the nutritional needs of the embryo until it hatches. The outer covering of the egg case is a tough, horny material. Each of the corners of the egg case is drawn out into a long coiled filament, or tendril, that wraps around rocks, kelps, or other materials on the sea floor, preventing the egg case from being carried away by currents and exposed to possible predation.

Structures of the Male and Female Reproductive System in Reptiles

In reptiles e.g. lizard, the male has two testes located in the abdominal region. Tiny vessels emerge from the testes where sperm cells led to the epididymis. These vessels are known as vasa efferentia. Each epididymis opens into two protusitle penes.

In the female lizard the ovaries are found at the two sides of the abdomen. The oviducts open into the cloaca. During mating, the male penis penetrated through the female cloaca into the opening of the oviduct while the seminal fluid that contains sperm is released into the oviduct.[]

Parts of the Reproductive Systems and their Functions

Parts of the Reproductive System of Fish and their Functions

Some parts of the reproductive system of fish and their functions are as follows:

1. Testis – Production of sperms.
2. Ovary – production of ovaries
3. Seminal vesicle – storage of sperms
4. Cloaca – genital opening.

Parts of the Reproductive System of Reptiles and their Functions

Some parts of the reproductive system of reptile and their functions are:

1. Ovoid testes: produces sperm cells.
2. Vas deferens: tiny vessels that carry sperms to the epididymis.
3. Ovaries: produce eggs.
4. Male penis: releases sperm into the oviduct

Structures of the Male and Female Gametes (Sperm and Ovum)

The male gametes of both fish and reptile are the sperm cells which are unicellular and mobile.

The female gametes on the other hand are the ova (ovum; singular) which are also unicellular but larger in size than the sperms, they are also called eggs. They are produced by the ovary.

In reptiles the eggs have hair-like structures surrounding it which enable it to move into the oviduct.

Differences between Male and Female Reproductive Organs

There are significant differences between the male and female reproductive organs of fish and the reptile.

Differences between Male and Female Reproductive Organs of Fish

For the fish, the basic differences are as indicated in the table below:

Differences between Male and Female Reproductive Organs of Reptiles

In reptiles the basic differences in their reproductive organs are as follows:

Presentation

The topic is presented step by step

Step 1:

The class teacher revises the previous topics

Step 2.

He introduces the new topic

Step 3:

The class teacher allows the pupils to give their own examples and he corrects them when the needs arise

Conclusion

The class teacher wraps up or conclude the lesson by giving out short note to summarize the topic that he or she has just taught.

The class teacher also goes round to make sure that the notes are well copied or well written by the pupils.

He or she does the necessary corrections when and where  the needs arise.

EVALUATION

1. 1. How are fungal diseases by pests controlled in crops?
   2. What is usually involved in the cultural methods of the control of plant diseases caused by pest?
   3. In a tabular form, outlines 5 common pests of crops, their symptoms and their control.
   4. Explain 4 pest control methods applicable to crops.
   5. Discuss the benefits and disadvantages of the use of Biological and chemical methods of pest control.
   6. What is crop rotation? Explain its benefits to pest control.
   7. State two differences between the male and female reproductive organs of a named fish.
   8. Mention two differences between the male and female reproductive organs of agama lizard.
   9. State 4 differences between the reproductive systems of a male and a female fish.
   10. State the functions of the following structures in the reproductive organs in reptiles.
   11. Seminal vessicle (b) Epididymis (c) Testis (d) Cloaca.
   12. Tabulate the differences in the fish male and female reproductive organs.
   13. Briefly describe the male gamete of a fish.
   14. Name the structures that produce the male and female gametes in reptiles.
   15. In what way are the functions of the testes related to that of the ovary.
   16. What are functions of the following parts of a fish reproductive system: (i) Testes (ii) Vasa efferentia (ii) Seminal vesicle (iii) Epididymus
   17. What is reproduction?
   18. Mention any parts of the reproductive system of a bony fish (male)
   19. Mention any parts of the reproductive system of a reptile (female)