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Kontrak kuliah Prinsip dasar reproduksi hewan. Nilai Akhir = 40% UTS + 40% UAS + 20% Tugas . Reproductive System. Sexual reproduction → gametes (the sperm and the ovum → produced by two parents)
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Kontrak kuliah Prinsip dasar reproduksi hewan
Reproductive System • Sexual reproduction →gametes(the sperm and the ovum → produced by two parents) • Each gamete → formed by meiosis 4→ contains only half the chromosomes of the body cells (haploid). • Fertilization → results in the joining (male and female gametes) → form a zygote which contains the full number of chromosomes (diploid). • The zygote then starts to divide by mitosis→ form a new animal with all its body cells containing chromosomes that are identical to those of the original zygote
Fertilisation External fertilization: In most fish and amphibia (frogs and toads) fertilisation of the egg cells takes place outside the body. The female lays the eggs and then the male deposits his sperm on or at least near them. Internal fertilization: In reptilesand birds, eggs are fertilized inside the body when the male deposits the sperm inside the egg duct of the female. The egg is then surrounded by a resistant shell, “laid” by the female and the embryo completes its development inside the egg. In mammals the sperm are placed in the body of the female and the eggs are fertilized internally → develop inside the body of the female → born → milk excreted from the mammary glands and protected by their parents
Sexual Reproduction In Mammals The reproductive organs of mammals produce the gametes (sperm and egg cells), help them fertilise and then support the developing embryo.