Turtle Dissection
Scientists believe
other land vertebrates
evolved from BONY
LOBE-FINNED fish
TURTLELATIN meaning
KINGDOM _____________
PHYLUM ____________________________
SUBPHYLUM ___________________________
CLASS _______________________________
ORDER _____________________________
ANIMALIA
CHORDATA
VERTEBRATA “backbone”
REPTILIA “to creep or crawl”
CHELONIA “tortoise”
INTEGUMENT
THICK, DRY,
SCALY SKIN
Contains KERATIN (protein)
LIPIDS & PROTEINS make it water tight
ADVANTAGES over
thin, moist Amphibian skin
1. WATER TIGHT
- Keeps them from drying out on land
2. TOUGH PROTECTION –
- prevents injury, keeps out germs,
- prevents wear & tear on skin
when crawling around on land
SHELL IS LIVING PART OF BODY
Expanded ribs form shell
Can regenerate damaged scutes
Growth rings tell age
Limbs at right
angles to body
Location of
Pelvic and
Pectoral girdles
allow turtle to
pull limbs into
shell
http://www.biosci.ohio-state.edu/~eeob/anatomy/eeob512/miscellaneous/turtleskeleton.jpg
Nictitating membrane
Tympanic membrane
External nares
Only reptiles with NO TEETH
Claws on feet
VENT
WHAT SEX IS IT?
FEMALES: MALES:
Short tail Longer tail
Vent closer Vent farther from body
MALE PLASTRON
slightly CONCAVE
to fit on top of female
CURVE OF PLASTRON
FEMALE PLASTRON
slightly CONVEX
to make more room for eggs
INTERNAL FERTILIZATION
Increases chances of
sperm and egg meetingImage from:
http://www.turtletimes.com/PhotoContest/2001PhotoContests/May2001/Geoemyda%20spengleri%20mating.jpg
Penis deposits sperm inside female’s body
GLOTTIS – respiratory opening
PHARYNX
GULLET
GLOTTIS
INTERNAL NARES
Ectothermic• Body heat comes from
surrounding environment
• Slow metabolism/low activity in
cold places
• “cold-blooded”
• EX: All invertebrates,
fish, amphibians, reptiles
ECTOTHERMICADVANTAGES:
Slow metabolism means you can survive
on 1/10 the food as a same size endotherm
DISADVANTAGES:
• Can’t to live in extremely cold places
(NO reptiles in Arctic)
• Can’t keep up max activity level for long
Endothermic “warm-blooded”
• Create own body heat
• FAST metabolism allows for:
high activity for extended time
ability to live in variety of environments
• EX: Birds, Mammals
PELVIC &
PECTORAL
GIRDLES
inside ribs
PERICARDIAL
MEMBRANE
Covers &
protects heart
EXCRETORY
URINARY
BLADDER
Image from:
http://theturtlepages.crosswinds.net/anatomy/index.html
Vent
LIVER
Makes BILE
Stores GLYCOGEN
Stores VITAMINS
Processes TOXINS
including nitrogen
waste for kidneys
Image from:
http://www.spc.cc.tx.us/biology/jmckinney/Studyimages/turtle/turtledissectlist.html
GALL
BLADDER
Stores BILE
STOMACH
Add ACID; Start DIGESTION; Grind & mash food
MESENTERY
PANCREASIn mesentery near first loop of small intestine
Makes TRYPSIN, INSULIN, GLUCAGON
SMALL INTESTINE
Duodenum
Ileum
LARGE INTESTINE(Also called COLON)
CLOACA
SPLEENMake, store, recycle RBC’s
TURTLE HEART
3 CHAMBERS
2 atria; 1 ventricle
Sinus Venosus &
Conus Arteriosus
are smaller
PARTIAL SEPTUM:
begins to divide ventricle into two sides
Image from: BIODIDAC
FISH
Sinus
venosus
RIGHT
Atrium
VentricleConus
arteriosus
Lungs
Body
organs
LEFT
Atrium
FROG/TURTLE CIRCULATION
REPTILESCan bypass lungs to save energy
• Holding breath underwater• Hibernating• When want to warm up
quickly
ENDOCRINEGlands that make
hormones that
control other body
organs
THYROID: located above heart
Makes hormones that control heart rate,
blood pressure; cell development and growth
PANCREAS controls
blood sugar levels
TRACHEA & ESOPHAGUS
BRONCHI
LUNGS HAVE ALVEOLI
FROG LUNG TURTLE LUNG
Increase surface area for more gas exchangeImages modified from:
http://www.stclement.pvt.k12.il.us/studentWeb/science98/GarrittPatM/alveoli.gif
REPRODUCTIVE
MALE FEMALE
Images modified from:
http://theturtlepages.crosswinds.net/anatomy/index.html
VentVent
OVARY-
• make eggs
OVIDUCT-
• add shells
• transport to
cloaca
Image from: BIODIDAC
EPIDIDYMIS –sperm mature here;
add tails
TESTES –
make sperm
INTERNAL FERTILIZATION
Increases chances of
sperm and egg meetingImage from:
http://www.turtletimes.com/PhotoContest/2001PhotoContests/May2001/Geoemyda%20spengleri%20mating.jpg
DIRECT DEVELOPMENT
Image from:
http://www.neuroscientist.com/animimag/turtles.htm
SEX is determined by
TEMPERATURE of NEST
Image from:http://www.parcplace.org/documents/GeneralHerpInfo/learnabout2.htm
Types of Reproduction
Ways offspring enter world
OVIPARITY- Reproductive tract encloses egg in a protective shell
Eggs deposited outside body to hatch
Nourishment comes from egg
EX: Most reptiles,birds & a few mammals
(monotremes)
VIVIPARITY-
No shell around egg
Eggs retained in body
Nourished by mother through
placenta
Offspring are born alive
Ex: Mammals & some reptiles
Ways offspring enter world
OVOVIVIPARITY-Egg surrounded by protective shellbut kept in body until just before hatching or can hatch inside female
Nourishment comes from egg not mother
Ex: Some reptiles (snakes)
Ways offspring enter world
OVI
PARITY
OVOVIVI
PARITY
VIVI
PARITY
SHELL?
NO SHELL?
Embryo
grows?
Food comes
From?
Seen in?
SHELL
OUTSIDE
EGG
Birds,
Reptiles,
Few mammals
NO SHELL
INSIDE
MOTHER
Mammals,
few reptiles
SHELL
INSIDE
EGG
Reptiles
AMNIOTIC EGG
NERVOUS
• COMPLEX BRAIN
• DORSAL SPINAL CORD
(Spine is fused to shell)
TURTLE BRAIN
BIGGER CEREBRUM than same sized amphibian
Image modified from: http://theturtlepages.crosswinds.net/anatomy/reprodexc.html
WHAT’S IN REPTILES?
Internal fertilization- (Penis)
increases chances of sperm finding egg
allows addition of protective shell
Amniotic eggs-
can lay eggs on land now;
better protection for embryos
Partial septum-better separation on high/low oxygen blood
WHAT’S IN REPTILES?
Other kinds of reproduction-
(OVOVIVIPARITY; VIVIPARITY)
increases chances for offspring survival
Control over Pulmonary circulation
can shift blood away from lungs to
body when neededDry, scaly skin
better able to live on land
WHAT’S IN REPTILES?
Nitrogen waste = uric acid
AMMONIA UREA URIC ACID
Least toxic form;
Needs least water to dilute
conserves water
Bigger cerebrum-
“smarter”; more complex behaviors
WHAT’S IN REPTILES?
LUNGS have ALVEOLI
increases surface area for more
gas exchange
Sex depends on temperature of eggs-
can change sex based on
population needs
