1. Reproductive System in Animals
By: Kaitlin, Kayleen & Stephanie

2. Function Continue the existence of a species
Individuals can multiply selves
Reproductive tissue usually is separate one to form a new organism
Cells: sperm and egg join to produce offspring

3. How it works: Asexual Reproduction
Independent sexual reproduction that doesn’t need union of male/female germ cells
Uncommon, certain invertebrates can perform

4. Asexual Reproduction Continued
Hermaphroditism: one organism has both reproductive systems to reproduce
Sequential hermaphroditism: an organism changes sex during its life
- produce offspring without mating
Parthenogenesis: an unfertilized egg to develop and hatch (insects)

5. How it works: Sexual Reproduction
Union of 2 sets of DNA which usually comes from different parents
Gonads: organ producing
reproductive cells, needed in process
- Male = testes: produce sperm
- Female = ovaries: make eggs
Sperm need wet environment get to egg
Must meet when gonads contain mature gametes

6. Porifera

7. Porifera Sexual: sponges usually cross-fertilize one another
Eggs and sperm join to produce a free-swimming larva settles on surface (rocks)
Asexual: gemules (internal buds)
Small cuts of sponges reproduce into a full-bodied sponge

8. Cnidarians Asexual/Sexual Most Jellyfish - both reproductive systems
Multible Stages
Polyp Stage: larva settles to the bottom, attaching self to a hard surface transforming into a polyp

9. Cnidarians: Egg Stage and Poly Colony Stage
Egg Stage: Fertilized eggs develop inside the female or in pouches on the oral arms
Larva is a short stage
- leave mouth or pouch as
free-swimming larva.
Poly Colony Stage: Polyp
develops into a polyp colony kept
together by feeding tubes

10. Cnidarians cont. Ephyra & Medusa stage
Polyp colony reproduce asexually and bud off tiny free-swimming jellyfish (called Ephyra)
Ephyra grow in size and become adult Medusa (form of jellyfish)

11. Platyhelminthes Flatworms = hermaphrodites
Eggs of each animal become fertilized from sperm of partner
Eggs are laid in cocoons
Yolk supplies
with nourishment
Then…hatch

12. Roundworms Reproduce sexually Separate sexes Chitinized spicules move
into genital pore of the female.
Sperm crawl along the
spicule into female worm

13. Annelids: Worms and Leeches

14. Annelids Sexually - some external fertilization
- some hermaphrodites (rarely fertilize selves)
- two worms attach – exchange sperm and store in sacs until eggs ready to be fertilized
- mucus ring forms and a cocoon is produced to hold embryos

15. Mollusks Sexually Male shed sperm into water
Fertilization in body of female water flow brings in sperm from male

16. Arthropoda: Insecta Insecta: separate sexes
Reproduction is usually sexual
- some eggs can develop without fertilization by sperm

17. Arthropoda: Crustacea
- Fertilization when eggs laid
- egg sticks to the female’s swimmeret
- carries eggs until developed/survive on own.

18. Arthropoda: Arachnida
Arachnida: Sexual reproduction
-Developing embryos protected until ready to be born by
- egg case - cocoon - on female

19. Echinodermata Sexual reproduction Uses external fertilization
Have separate sexes

20. Chordata: Fish Sexually Female lays eggs Male fertilizes with a
spray of liquid of
sperm cells
Yolk feeds the fish in
the egg

21. Chordata: Amphibians Reproduces sexually
Eggs fertilized outside of the mother's body
Father immediately comes by and fertilizes them

22. Chordata: Reptiles Reproduces sexually
Female's eggs fertilized by the male internally
Egg then laid

23. Chordata: Aves (Birds)
Reproduce sexually
Fertilization: male place sperm in the female
Bird lays eggs: protective
shell
Male often help keep eggs
warm until hatched

24. Chordata: Mammal Reproduce sexually
Female fertilized internally by male

25. Interesting facts
In internal fertilization: a female not willing to mate often will injure/kill an aggressive male
In sea horses, the males become pregnant
At five to six weeks of age male mice reach puberty
Snails are hermaphrodites but still need to mate to produce fertile eggs

26. Reproductive system interactions
Only system not necessary for an individual organism to live
Doesn’t depend on any other system to work
Endocrine system
- hormones in the bloodstream
- system that interacts with reproduction

27. Possible Test Questions
What is the Purpose of the Reproductive System?
Define and explain the two reproduction processes?
True/False: Hermaphrodites always reproduce with self.

28. Answers
What is the Purpose of the Reproductive System?
Continue the existence of a species and for individuals to multiply selves
Define and explain the two reproduction processes?
Sexual: 2 sets of DNA, Sperm must meet egg to fertilize
Asexual: Independent reproduction not needing union of male/female cells
True/False: Hermaphrodites always reproduce with self.
False: Sometimes mate with other animals (Annelids) though have both parts

29. If Egg were to be fertilized….
Beginnings of embryo.
As it grow, consume yellow part: yoke