WEEK 5: REPRODUCTIVE SYSTEM IN FISH, AMPHIBIAN, REPTILE AND BIRDS

TOPIC: Reproductive System in Fish, Amphibian, Reptile and Birds 
MAIN AIM: To help the learners understand reproductive system in fish, amphibian, reptile and birds
SUSIDIARY AIM: By the end of the lesson, learner should be able to;

1. Explain the reproductive system of fishes and amphibians
2. Explain the reproductive system of reptiles and birds
3. Explain the reproductive system in female reptiles and birds

PERSONAL AIM: To keep strictly to time allotted to  each stage of the lesson
PREVIOUS KNOWLEDGE: The learners learnt reproduction in their previous  lesson
TEACHING AIDS: Research work from the internet, pictures
PROCEDURE: The teacher present the lesson with the following steps
STEP ONE:  REPRODUCTIVE SYSTEMS OF FISHES AND AMPHIBIANS

MALE REPRODUCTIVE SYSTEMS: Male fishes and amphibians have two testes for production of spermatozoa. Each testis is joined by fine tubules called vasa efferentia to sperm-conducting tubules in the anterior part of the kidney. These kidney tubules drains into a common duct called Wolffian duct. The Wolffian duct transports both urine and sperms into the cloaca. In some frogs and toads, each Wolffian duct enlarges at its posterior region to form a sac called seminal vesicle where sperm cells are stored until copulation.

   DIAGRAM OF FEMALE REPRODUCTIVE SYSTEM OF FROG
Parts of female reproductive system of amphibians and fishes and their functions

1. Ovaries produce egg cells.
2. Oviduct is the tube where produced eggs pass and enter the cloaca.
3. Cloaca is the opening for the passage of the eggs to the exterior.

STEP 2: REPRODUCTIVE SYSTEMS OF REPTILES AND BIRDS

Male Reproductive System of Reptiles: Male lizards and snakes have a pair of copulatory organs called hemipenes. The hemipenes are sac-like and lack erectile tissue. They are found at the base of the tail. Only one is used at a time during copulation and are not involved in urination. The reptiles have a pair of testes near the kidneys. A sperm duct from each testis leads into the cloaca and joins the hemipenis. The hemipenis is used to introduce sperm into the cloaca of the female.
Male Reproductive System of Birds: birds do not have penis. They have a pair of testes for production of sperm cells. Sperm ducts from each testis connect the testis to the cloaca. The sperm ducts expand at their posterior end to form seminal vesicle where the sperm cells are stored until copulation. During copulation, sperms are introduced from the seminal vesicle to the female when their cloacae come in contact.

STEP THREE: FEMALE REPRODUCTIVE SYSTEM OF REPTILES AND BIRDS

Female reptiles have two ovaries and oviducts. The oviducts open internally into the body cavity and lead posteriorly to open into the cloaca.
Female birds have one ovary and on oviduct. This is because only the left side of the reproductive system is developed. The ovary produces the eggs which are transferred into the oviduct through the body cavity. At the oviduct, the eggs are covered with albumen, shell membranes and shells secreted by glands at the posterior part of the oviduct, before they are laid. The eggs are laid into the external environment through the cloaca.

 
EVALUATION:

1. Explain the reproductive system of fishes and amphibians
2. Explain the reproductive system of reptiles and birds
3. Explain the reproductive system in female reptiles and birds

CONCLUSION: The teacher concludes the lesson by summarizing the topic from the beginning and give assignment to the learner.
ASSIGNMENT:
Draw the reproductive system in female reptiles and birds