Reptile Notes

Reptile Notes

By Teresa Schlueter

Multiple Choice

The 8 levels of classification, from most broad to most specific are ...

• Domain, Genus, Family, Order, Class, Phylum, Kingdom, Species
• Domain, Species, Kingdom, Genus, Phylum, Family, Class, Order
• Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species
• Order, Kingdom, Species, Domain, Phylum, Family, Class, Genus

Multiple Choice

To what domain do Reptiles belong?

• Eukarya

• Prokarya

• Archaea

Multiple Choice

To what kingdom do reptiles belong?

• Plantae

• Protista

• Fungi

• Animalia

Multiple Choice

To what phylum do reptiles belong?

• Echinodermata

• Reptilia

• Chordata

• Platyhelminthes

Multiple Choice

To what class do reptiles belong?

• Amphibia

• Reptilia

• Aves

• Mammilia

External Structure and Locomotion

•  A reptile is a vertebrate that has dry, scaly skin, lungs, and terrestrial eggs with several membranes.

  •  These characteristics enable reptiles to live their entire lives out of water.

External Structure and Locomotion

•  Reptilian skin is dry and covered with thick, protective scales.

  • This prevents the loss of body water in dry environments.

  • The scaly layer of skin doesn’t grow, so it must be shed periodically as the reptile increases in size

Multiple Choice

What is happening here?

• Ecdysis

• Epistasis

• Ectoparasite

• Ectothermy

External Structure and Locomotion

•  Scales are modified for various functions

  •  Snakes have large belly scales that they use for locomotion

  •  Lizards and turtles have legs for locomotion

Multiple Choice

What are most reptile scales made from?

• Skeleton

• Epidermis (skin)

• Fur

• Brain

Multiple Choice

Which is NOT a characteristic of a reptile?

• Warm Blooded
• Scaly skin
• Has lungs
• lays leathery eggs

Nutrition

• ​Most reptiles are carnivores – turtles can be herbivores, carnivores, or omnivores.

• Tongues of turtles and crocodilians are nonprotrusible (non - can’t, protrusible - stick it out) and aid in swallowing.

—

​

Nutrition

​—

• Some lizards and the tuatara have sticky tongues.

​

Nutrition

• ​Snakes have the ability to unhinge their jaw and have a split lower jaw that allows them to ingest prey much larger than a snake’s normal head size.

  • Posteriorly pointing teeth prevent prey escape and help force food into the esophagus.

  • Some snakes possess venom glands to quiet their prey during swallowing.

Digestive System

• ​ESOPHAGUS - carries food to stomach

• STOMACH - uses acids and muscle contractions break down food;

• PYLORIC SPHINCTER - controls food moving from stomach to small intestine

Digestive System

• ​SMALL INTESTINE - (split into 2 sections)- finishes digestion/absorbs nutrients;

  •  DUODENUM-(closest to stomach) receives bile and trypsin/completes digestion

  •  ILEUM- coiled middle section-absorbs nutrients (fingerlike VILLI inside increase surface area)

Digestive System

• ​LARGE INTESTINE (also called COLON) absorbs water/concentrates digestive waste;

• CLOACA- receives feces, urine, eggs/sperm,

• VENT- exit opening in animals with a cloaca

Turtle Digestive system

Digestive System

• LIVER- ( 4 functions)

  •  makes bile

  •  stores glycogen

  •  Store vitamins

  •  processes toxins for kidneys

• GALL BLADDER- stores bile;

• MESENTERY-connects internal organs and hold them in place

Endocrine System

• ​ Thyroid Gland

  •  Regulates heart rate, metabolism, and reproduction

•  PANCREAS- (3 functions)

  •  makes digestive enzymes (trypsin) for small intestine

  •  Makes insulin

  •  makes glucagon

Multiple Choice

The _____ brings food from the mouth to the stomach.

• esophagus

• mouth

• stomach

Multiple Choice

The chewing and grinding of food into smaller pieces is an example of...

• Mechanical Digestion
• Chemical Digestion

Multiple Choice

What membrane holds the small intestine in a folded position?

• greater omentum
• mesentery
• lesser omentum
• falciform ligament

Multiple Choice

This part stores bile produced by the liver. 

• Gall Bladder
• Pancreas
• Stomach
• Rectum

Multiple Choice

This produces digestive juices that help to further break down the food in the small Intestine. It also produces insulin.

• Stomach

• Liver

• Gall Bladder

• Pancreas

Circulatory System

• ​ Reptiles have a double-loop circulatory system:

  •  One loop brings blood to and from the lungs. (Pulmonary loop)

  •  One loop brings blood to and from the rest of the body. (Systemic loop)

    ​

Circulatory System

• Reptile hearts have two atria and either one or two ventricles.

  •  Most reptiles have one ventricle with a partial septum that separates oxygen-rich and oxygen-poor blood.

  •  Crocodiles and alligators have two atria and two ventricles.

Circulatory System

Respiratory System

• ​Reptile lungs are spongy, allowing for a larger area of gas-exchange.

•  Many reptiles have muscles around the ribs that expand and collapse the chest cavity.

•  Most reptiles have two lungs, but certain species of snakes have just one lung.

• ​When Turtles hibernate under water they can breath through their cloaca.

Multiple Choice

Where can turtles do cutaneous gas exchange while hibernating underwater?

• Cloaca

• Neck

• Shell

• Tongue

Multiple Choice

Reptiles mostly breathe through lungs.

• True

• False

Temperature Regulation

•  Reptiles are ectotherms.

  •  Ectotherms are animals that rely on behavior to control body temperature.

  •  To warm up, they bask in the sun or stay under water at night.

  •  To cool down, they move to the shade or take shelter in underground burrows.

Multiple Choice

Is a reptile cold-blooded or warm blooded?

• Warmblooded
• Cold-blooded
• Neither
• Both

Multiple Choice

Most reptiles are...

• Diurnal and ectothermic

• Diurnal and endothermic

• Nocturnal and ectothermic

• Nocturnal and poikilothermic

Nervous system

• ​Vision is the dominant sense in most reptiles.

• Upper and lower eyelids, a nictitating membrane, and a blood sinus protect and cleanse the surface of the eye.

Nervous system

• Reptiles have simple ears with an external eardrum (tympanic membrane) and a single bone (columella) that conducts sound to the inner ear.

Nervous system

• Snakes can also pick up vibrations in the ground through bones in their skulls.

• Some snakes can detect the body heat of their prey.

• Reptiles sense of smell is more developed than the amphibians. 

• Most reptiles have sensory organs in the mouth that detect chemicals when reptiles flick their tongues.

Excretory system

• Urine is produced in the kidneys.

  •  In some reptiles, urine flows in tubes directly into a cloaca.

  •  In others, a bladder stores urine before it is expelled.

Excretory system

• Other reptiles convert ammonia into uric acid.

  •  In the cloaca, urine is reduced to crystals of uric acid that form a pasty white solid.

  •  By eliminating solid wastes, a reptile can conserve water.

Reproduction

• ​ Most reptiles are oviparous, laying eggs that develop outside the mother’s body.

•  All reptiles reproduce by internal fertilization, in which the male deposits sperm inside the female’s cloaca.

•  After fertilization, the female’s reproductive system covers the embryo with several membranes and a leathery shell.

• The sex of reptiles is determined by the temperature and placement within a nest unlike in mamals where sex is determined by the X and Y chromosome.

•  This type of egg, an amniotic egg, is one of the most important adaptations to life on land. 

The Amniotic Egg

• The amniotic egg them to reproduce and develop without running water.

• The shell and membranes protect the embryo and prevent the egg from drying out.

  •  4 membranes:

    •  CHORION-surrounds all membranes/protection

    •  AMNION-encloses embryo & fluid

    •  YOLK SAC-encloses food supply

    •  ALLANTOIS- stores nitrogen waste​

• ​ALBUMEN = protein & water surrounds the membranes (egg white)

Multiple Choice

___________ is when young hatch from an egg outside the mother’s body.

• oviparous

• ovoviviparous

The Amniotic Egg

Multiple Choice

Which part of an amniotic egg helps excrete wastes & exchange gases?

• Allantois

• Chorion

• Amnion

• Albumen

Multiple Choice

How is the sex of a reptile determined?

• Based on the temperature at which the eggs are incubated.

• Based on the temperature when the eggs are fertilized.

• Whether they have XX or XY chromosomes.

• There are not separate sexes because they are hermaphroditic.

Multiple Choice

Which part of the amniotic egg is the outermost membrane?

• Chorion

• Amnion

• Allantois

• Yolk sac

Multiple Choice

Which of the following is NOT true of any reptiles?

• Internal fertilization

• External fertilization

• Oviparous

• Viviparous

Multiple Choice

This is the part of the amniotic egg that surrounds the embryo with fluid to cushion it.

• Amnion

• Allantois

• Albumen

• Yolk Sac

Multiple Choice

What part of the amniotic egg is known as the "egg white" and is made up of proteins?

• Albumen

• Allantois

• Chorion

• Yolk sac

Orders of Reptiles

​Order: Testudines or Chelonia

• ​Turtles and tortoises

  •  Latin word test = shell

  •  Only vertebrates with hard shells that surround and protect organs

•  Shell is in 2 parts

  •  Top = carapace

  •  Bottom = plastron

•  They lack teeth

Orders of Reptiles

Multiple Choice

What order to turtles & tortoises belong to?

• Testudines

• Crocodilia

• Rynchocephalia

• Squamata

Multiple Choice

What are the two parts of a turtle's shell?

• Carapace is dorsal and plastron is ventral

• Carapace is ventral and plastron is dorsal

• Carapace is anterior and plastron is posterior

• Carapace is posterior and plastron is anterior

Orders of Reptiles

​Order: Squamata

Most diverse retile order

Includes

•  Suborder Lacertilia =Lizards

  •  4 limbs

  •  Visible ear openings

  •  Movable eyelids

​

​

​ Suborder Serpentes = Snakes

•  Lack limbs

•  Lack eyelids

•  No external ear openings

•  Split lower jaw

Orders of Reptiles

​Order: Squamata​

• Keratinous scales cover their bodies

•  Go through ecdysis when they outgrow their skin

• Transverse vent and more movable skulls than other reptiles.

Orders of Reptiles

Suborder Serpentes = Snakes

• —3 different types of serpents / snakes

  •  Elapids

    • Inject venom into their prey using immovable fangs

      •  EX: cobra, mamba

  • Vipers

    • Inject venom into their prey using movable fangs

      • EX: adders, rattlesnakes

  • Constrictors

    •  Squeeze their prey until they suffocate

      • EX: pythons and boas

​

Multiple Choice

Order that includes lizards and snakes?

• Squamata

• Testudines

• Crocodilia

• Rynchocephalia

Multiple Choice

Pit-like sense organ in the roof of a snake's mouth; removes scent molecules from the tongue and transmits information to the brain

• spectacle

• plastron

• Jacobson's organ

• pit organ

Orders of Reptiles

​Order: Crocodilia

• Includes Crocodiles, Alligators, and Caimans

  •  Long flattened snouts

  •  Laterally compressed tails

  •  Eyes, ears, and nostrils on top of the head

  •  Semiaquatic

  •  Carnivorous predators​

Orders of Reptiles

• ​Crocodile

  •  V-shaped nose

  •  No overbite

  •  Dagger-shaped teeth

• Alligator

  •  Rounded nose

  •  Slight overbite

  •  Conical shaped teeth

• Caiman

  •  Rounded nose

  •  Oversized upper jaw

  •  Dagger shaped teeth

  •  Smallest overall body size

Multiple Choice

All of the following belong in Crocodilia EXCEPT...

• Tuatara

• Alligators

• Crocodiles

• Caimans

Multiple Choice

The order ___________ contains crocodiles and alligators.

• Rhynchocephalia

• Chelonia

• Squamata

• Crocodilia

Orders of Reptiles

Order: Rhynchocephalia or Sphenodontia

• Only 1 living species

  •  Tutara in New Zealand

• 2 rows of teeth in the upper jaw

• They have a third eye on top of their head

  •  Not used for seeing

  •  Covered by scales in adults

  •  Light sensitive for determining time of day

Multiple Choice

What is unique about a Tuatara's teeth?

• They are thecodont teeth

• They have two rows on the top and one on the bottom

• They don't have any teeth

• They can be replaced throughout its lifetime

Multiple Choice

Match the following: Order for Turtles

• Testudinata

• Amphisbaenia

• Sauria

• Spenodonata

• Squamata

Multiple Choice

Match the following: Order for Tuatara

• Crocodilia

• Amphisbaenia

• Sauria

• Spenodonata

• Squamata

Multiple Choice

Match the following: snakes and lizard order

• Crocodilia

• Amphisbaenia

• Serpentes

• Spenodonata

• Squamata

Multiple Choice

Match the following: suborder for snakes

• Crocodilia

• Amphisbaenia

• Serpentes

• Spenodonata

• Sauria

Multiple Choice

Match the following: Order for Alligators

• Testudinata

• Crocodilia

• Squamata

• Spenodonata

• Sauria

Comparative Anatomy of Circulatory Systems