Reptile Species Considerations

Question 1

What are the 2 orders of Chelonia? What are the differences between these?

Answer 1

Pleurodira - 3 flexion points of head, can’t fully withdraw

Cryptodira - 2 flexion points, can withdraw

Question 2

Auscultation is hard with Chelonia due to the shell. What can we do to make this easier?

Answer 2

Wrap in a damp towel

Question 3

What type of poikilothermic ectotherms are Chelonia? What is a problem associated with this?

Answer 3

Heliotherms - heat from basking

Difficulty cooling

Question 4

What type of skulls do chelonians have? Do they have teeth?

Answer 4

Analysis

No teeth - use sharp beak for prehension. Egg tooth to open shell

Question 5

What is the shell of Chelonia composed of?

Answer 5

Keratinised scutes

Question 6

What is the upper shell of Chelonia called?

Answer 6

Carapace

Question 7

What is the lower shell (ventral) of Chelonians called?

Answer 7

Plastron

Question 8

In Chelonia, the not well developed rib cage is fused to the spine. What structures are within the rib cage? What effect does this have?

Answer 8

Pectoral and pelvic girdle

Limits locomotion

Question 9

What are the names of the scutes found in the central of the carapace? What about the ones next to these? What are the outside scutes called?

Answer 9

Vertebral
Pleural
Marginal

Question 10

What are the scutes found below the neck called?

Answer 10

Nuchal

Question 11

Where are the lungs found in Chelonia? How are they separated from the abdomen?

Answer 11

Below the carapace

Pleura

Question 12

What type of breathers are Chelonia? How is their respiratory system adapted for their anatomy?

Answer 12

nasal breathers. Respiratory breathing = distress

Short trachea - can breathe with neck fully drawn in

Question 13

Do any reptiles have a diaphragm?

Answer 13

No

Question 14

Why are chelonians susceptible to pneumonia?

Answer 14

No cough reflex

Question 15

Describe the kidneys in Chelonia. Where are they found?

Answer 15

Paired, Lobulated

Beneath the dorsal carapace

Question 16

In what form do chelonians excrete waste?

Answer 16

Urea/uric acid

Question 17

Under what temperature does no digestion occur?

Answer 17

<7 degrees C

Question 18

How can you sex chelonia?

Answer 18

Tail length and thickness

Males have concave plastron

Question 19

What are 2 of the suborders of lizard?

Answer 19

Iguinia
Gekkata
Skincomoprha
Varinoidea

Question 20

Explain how lizards scales are adapted for light absorption

Answer 20

Change in colour in the day

Question 21

What type of skulls do lizards and snakes have?

Answer 21

Diapsid (2 temporal fenestrae)

Question 22

What is unique about the vertebrae in lizards and snakes?

Answer 22

All have ribs (except cervical)

Question 23

What type of kidneys do lizards have?

Answer 23

Lobulated

Question 24

What 2 problems are common with female repro in lizards?

Answer 24

Follicular stasis

Egg binding tooviduct

Question 25

What type of offspring do lizards produce? (In terms of live birth, egg etc)

Answer 25

All! Viviparous Oviparous Parthogenesis (asexual reproduction, no male)

Question 26

Where are testes found in male lizards?

Answer 26

Abdomen

Question 27

Which species have hemipenes? Where are they? What do they do?

Answer 27

Squamata only - snakes and lizards Stored in tail, can be exerted One is used during copulation (NOT for urination)

Question 28

How are hemipenes everted? What is a common problem with hemipenes?

Answer 28

Erectile tissue contraction | Prolapse

Question 29

What are 2 external differences between male and female lizards?

Answer 29

Males larger and more colourful | Males have femoral pores

Question 30

What are the 2 main groups of snake? What is the difference between these?

Answer 30

Boidae - 2 lungs, 2 carotid arteries, caecum | Colubridae - 1 lung, 1 carotid artery, no caecum

Question 31

Give examples of 2 boidae snakes

Answer 31

Boa | Anaconda

Question 32

Give 2 examples of colubridae snakes

Answer 32

Corn snake | King snake

Question 33

How can snakes use their shape to alter thermoregulation?

Answer 33

Coil up to retain heat | Uncoil to lose heat

Question 34

Do snakes shed fully? What is a common problem that owners worry about before this happens?

Answer 34

Yes - including spectacle | Eyes turn milky

Question 35

Only primitive snakes have vestigial limbs. What are these called? How do snakes move?

Answer 35

Pelvic spurs | Axial skeletal muscles

Question 36

What organs are found in each 1/3 of the snake

Answer 36

Cranial - heart, left lung, trachea, oesophagus, thyroid Middle - stomach, liver, lung, spleen, pancreas Caudal - intestines, kidney, gonads

Question 37

What are the modifications that allow snakes to eat large prey?

Answer 37

Kinetic skull with no mandibular symphysis = large gape Rostral glottis allows breathing whilst swallowing Skin between scales allow stretch

Question 38

What is the function of the tongue in snakes?

Answer 38

Touch Taste Olfaction (brings particles onto chemoreceptors on roof of mouth - vomeronasal organ)

Question 39

Why do snakes easily regurgitate? Which snakes are more likely to regurgitate?

Answer 39

Poor cardiac sphincter | Young, stressed

Question 40

What type of teeth do snakes have?

Answer 40

Pleurodont (attached to medial bone)

Question 41

Do snakes have eyelids? How are the eyes protected? Do they have sclerotic rings?

Answer 41

No Protected by the spectacle No

Question 42

Why do snakes have poor vision?

Answer 42

No ciliary body | Reduced eye movement

Question 43

Describe the lungs in a snake?

Answer 43

Smaller vestigial left lung (if present) Lungs are unicameral - one compartment Have faveoli

Question 44

Describe the kidneys in snakes

Answer 44

Paired Lobulated Elongated Males have sexual part to kidney

Question 45

Do snakes have a bladder?

Answer 45

No - ureters run straight into urodeum

Question 46

Which types of snakes have pelvic spurs? Where are they found?

Answer 46

Primitive - pythons, boas | Either side of the vent

Question 47

Describe olfaction in snakes

Answer 47

Very good due to Jacobson’s organ as well as normal olfactory cells

Question 48

Describe snakes ears. What bone picks up sound vibrations?

Answer 48

No external ear Internal ear only Quadrate bone

Question 49

How do snakes find prey in the dark?

Answer 49

Infrared sensor pits between mouth and eyes

Question 50

At what age do snakes mature? What is this based on?

Answer 50

1-5 years | Based on size not age!

Question 51

How can you sex a snake?

Answer 51

Males have thicker tail due to hemipenes Evert hemipenes Probe (most accurate)

Question 52

Where are testes found in snakes? What happens to hemipenes during the breeding season?

Answer 52

Above kidneys | Enlarge