turtle dissection - o'mara's science...

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