Turtle Dissection
Scientists believe
other land vertebrates
evolved from BONY
LOBE-FINNED fish
TURTLE
LATIN meaning
ANIMALIA
KINGDOM _____________
PHYLUM ____________________________
CHORDATA
VERTEBRATA “backbone”
SUBPHYLUM ___________________________
REPTILIA “to creep or crawl”
CLASS _______________________________
CHELONIA “tortoise”
ORDER _____________________________
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
Image from:
http://www.dfo-mpo.gc.ca/canwaters-eauxcan/bbb-lgb/creatures-animaux/reptiles/index_e.asp
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:
Short tail
Vent closer
MALES:
Longer tail
Vent farther from body
CURVE OF PLASTRON
MALE PLASTRON
slightly CONCAVE
to fit on top of female
FEMALE PLASTRON
slightly CONVEX
to make more room for eggs
INTERNAL FERTILIZATION
Penis deposits sperm inside female’s body
Increases chances of
sperm and egg meeting
Image from:
http://www.turtletimes.com/PhotoContest/2001PhotoContests/May2001/Geoemyda%20spengleri%20mating.jpg
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
ECTOTHERMIC
ADVANTAGES:
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
Vent
Image from:
http://theturtlepages.crosswinds.net/anatomy/index.html
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
PANCREAS
In mesentery near first loop of small intestine
Makes TRYPSIN, INSULIN, GLUCAGON
SMALL INTESTINE
Duodenum
Ileum
LARGE INTESTINE
(Also called COLON)
CLOACA
SPLEEN
Make, store, recycle RBC’s
TURTLE HEART
3 CHAMBERS
2 atria; 1 ventricle
Image from: BIODIDAC
Sinus Venosus &
Conus Arteriosus
are smaller
PARTIAL SEPTUM:
begins to divide ventricle into two sides
Sinus
venosus

 

RIGHT LEFT  Lungs

Atrium Atrium


Ventricle



 Body
organs


Conus
arteriosus
FROG/TURTLE CIRCULATION
ENDOCRINE
Glands that make
hormones that
control other body
organs
PANCREAS controls
blood sugar levels
THYROID: located above heart
Makes hormones that control heart rate,
blood pressure; cell development and growth
TRACHEA & ESOPHAGUS
BRONCHI
LUNGS HAVE ALVEOLI
FROG LUNG
TURTLE LUNG
Increase surface area for more gas exchange
Images modified from:
http://www.stclement.pvt.k12.il.us/studentWeb/science98/GarrittPatM/alveoli.gif
Images modified from:
http://theturtlepages.crosswinds.net/anatomy/index.html
REPRODUCTIVE
Vent
MALE
Vent
FEMALE
OVARY• make eggs
OVIDUCT• add shells
• transport to
cloaca
EPIDIDYMIS –sperm mature here;
add tails
TESTES –
make sperm
Image from:
BIODIDAC
INTERNAL FERTILIZATION
Increases chances of
sperm and egg meeting
Image 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)
Ways offspring enter world
VIVIPARITYNo shell around egg
Eggs retained in body
Nourished by mother through
placenta
Offspring are born alive
Ex: Mammals & some reptiles
Ways offspring enter world
OVOVIVIPARITYEgg surrounded by protective shell
but kept in body until just before hatching
or can hatch inside female
Nourishment comes from egg not mother
Ex: Some reptiles (snakes)
OVI
PARITY
SHELL?
NO SHELL?
Embryo
grows?
Food comes
From?
Seen in?
SHELL
OUTSIDE
EGG
Birds,
Reptiles,
Few mammals
OVOVIVI
PARITY
SHELL
INSIDE
VIVI
PARITY
NO SHELL
INSIDE
EGG
MOTHER
Reptiles
Mammals,
few 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 eggscan lay eggs on land now;
better protection for embryos
Partial septumbetter 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 needed
Dry, 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 eggscan change sex based on
population needs