1. 6S (13) Lee Michelle Ching Yin Reptile

2. We are reptiles ! Me too!

3. Class: Retilia General features: live on ground, while some can live in water as well poikilotherm most are carnivorous, except turtles are herbivorous breathe with lungs skin covered with scales/ scutes lay shelled eggs tetrapods

4. Body Structure

5. have lungs - crocodiles: muscular diaphragm  increase space for greater lung inflation

6. have horny epidermis  watertight  able to live on dry land exposed parts protected by scales & scutes

7. have three-chambered heart - 2 atria, 1 ventricle, 2 aortas - deoxygenated blood can be shunted back to the heart and oxygenated blood can be shunted back to the lungs  more effective thermoregulation  longer diving time

8. diurnal animals -vision can adapt daylight condition -with colour vision -more advanced vision depth

9. some snakes have heat-sensitive pits  sense the body heat of birds and mammals  hunt in the dark

10. lack a secondary palate - must hold their breathe while swallowing - except crocodiles & skinks - snakes: extend their trachea and stick out like a fleshly straw

11. camouflage -skin colour is usually grey, brown or green  blend into the background of the natural environment  avoid confrontation

12. Reproduction

13. most reptiles reproduce sexually all reproductive activities occur through the cloaca most reptiles have copulatory organs, which are usually retracted or inverted and stored inside the body

14. some squamates (lizards & snakes) are able to have asexual reproduction parthenogenesis females are able to produce a unisexual diploid clone of the mother

15. oviparous -most reptiles lay eggs covered with leathery or calcareous shells

16. ovoviviparous/ viviparous - ovoviviparous= embryos develop inside eggs, without placenta - viviparous= birth of offspring without the development of calcified eggs - evolved only in lizards & snakes

17. temperature-dependent sex determination - the incubation temperature determines whether a particular egg hatches as male or female - most common in turtles and crocodiles - sometimes occur in lizards and tuataras as well

18. Defense Mechanism

19. snakes crawl away into the underground hiss loudly vibrate the tip of the tail ( rattlesnakes) elevate the head and spread out the skin of the neck to look bigger and more threatening use venom to attack play dead

20. crocodiles expose the teeth and yellow tongue plunge into water and sink out of sight hiss loudly inflate the body to look bigger chase bite

21. lizards the tail has more vivid colour when captured by the tail  shed the part of the tail detached tail will continue to wiggle the tail can be regenerated

22. ReptilesAmphibians dry & scaly skinmoist & sticky skin with clawswithout claws breathe with lungs breathe with lungs & gills eggs have thick, hard shell eggs without protective outing covering eggs laid in buried, insulated nests eggs laid in water / damp places external fertilizationinternal fertilization do not have larval stage pass through larval stage before metamorphose into adult form

23. The End! Reference: http://en.wikipedia.org/wiki/Reptile http://en.wikipedia.org/wiki/Tempe rature- dependent_sex_determination http://en.wikipedia.org/wiki/Parthe nogenesis