The document discusses various modes of reproduction in animals. It describes asexual reproduction methods like budding and fragmentation where offspring are clones of the parent. It also covers sexual reproduction, noting external fertilization in many fish and internal fertilization in most other animals. Five main types of sexual reproduction are outlined: oviparity, ovoviviparity, histotrophic viviparity, hemotrophic viviparity, and hermaphroditism in which an animal can change or have both sexes simultaneously. Examples are provided for each method.

1. ANIMAL REPRODUCTION
Tony Ng

2. Reproduction
A fundamental biological
process in which new
individual organisms
("offspring") are produced
from their "parents"
Ensures the continuity of
the species

3. Reproduction
◉ Asexual Reproduction:
Parent produces genetically similar/identical offspring
◉ Sexual Reproduction:
Production of gametes (sex cells) via meiosis
Fusion of male and female gametes (fertilisation)

4. Fragmentation
Parthenogenesis
Types of Reproduction
in animals
Sexual ReproductionAsexual Reproduction
Budding Five modes of reproduction
Hermaphroditism

5. Fragmentation
Parthenogenesis
Types of Reproduction
in animals
Asexual Reproduction
Budding
Organism develops from an
outgrowth due to cell division at a
particular site on parent
E.g. sponges, corals, jellyfish, hydra

6. Fragmentation
Parthenogenesis
Types of Reproduction
in animals
Asexual Reproduction
Budding
Organism is split into fragments, each
of which develop into mature clones
May or may not be intentional
E.g. sponges, corals and echinoderms

7. Fragmentation
Parthenogenesis
Types of Reproduction
in animals
Asexual Reproduction
Budding
in animals
Organism (embryo) develops from
an unfertilized egg cell (after
meiosis)
Half clones or full clones
E.g. insects, some reptiles (lizards,
komodo dragon), sharks

8. Types of Reproduction
in animals
Sexual Reproduction
Five modes of reproduction
Hermaphroditism
(1) Ovuliparity
External fertilisation (egg cells
released into the environment and
fertilised by males)
Molluscs, arthropods, fishes and
most frogs

9. Types of Reproduction
in animals
Sexual Reproduction
Five modes of reproduction
Hermaphroditism
(2) Oviparity
- Internal fertilisation
- Lay eggs
- Little embryonic development
in mother
Most fish, amphibians, reptiles, all
birds, monotremes

10. Types of Reproduction
in animals
Sexual Reproduction
Five modes of reproduction
Hermaphroditism
(3) Ovoviviparity
- Internal fertilisation
- Embryos develop in eggs and
hatch within parent
- Give birth to live young
- No placenta
Some fish, amphibians and reptiles

11. in animals
Sexual Reproduction
Five modes of reproduction
Hermaphroditism
Viviparity
Development of embryo within
parent (give birth to live young)
Types of Reproduction

12. in animals
Sexual Reproduction
Five modes of reproduction
Hermaphroditism
(4) Histotrophic viviparity
Embryos acquire nutrients from:
1) other tissues (skin/glands)
2) oophagy (feeding on eggs
produced by ovary); e.g. some sharks
3) adelphophagy (fetus feeds on
sibling embryos); e.g. marine snails
and worms, some sharks
Types of Reproduction

13. in animals
Sexual Reproduction
Five modes of reproduction
Hermaphroditism
(5) Hemotrophic viviparity
Embryo acquires nutrients from
female (often from placenta)
E.g. most mammals
Types of Reproduction

14. Types of Reproduction
in animals
Sexual Reproduction
Five modes of reproduction
Hermaphroditism
Organism can have both male and
female reproductive organs
(A) Sequential hermaphrodites
Individual born as one sex but can
later change into the opposite sex
(B) Simultaneous hermaphrodites
Individual has both male and female
sexual organs at the same time (A) (B)

15. Group Activity
Kangaroo Slug Great White
Shark
Starfish Scorpion
Komodo
Dragon
Human Sea
Anemone
Clownfish Seahorse
Jellyfish Aphid Sea Turtle Cuckoo Frog
25 min to research and prepare a 5 min presentation on reproduction in 3 animals!

16. Guiding Questions
◉ How does mating take place?
◉ What is/are the method(s) of reproduction?
○ E.g. number of mates? length of gestation? how
does the animal give birth? number of young?
◉ Do parents care for the young?
◉ Any interesting facts?
◉ What are the advantages/disadvantages of such a
method of reproduction?

17. Thanks!