What does the term Herps refer to?
Reptiles and amphibians
Do amphibians have scales like reptiles?
The class reptalia includes what animals?
Snakes, lizards, chelonians, crocodiles
What order and suborder does the snake belong to?
What are the four families of snakes? Give examples of snakes found in each family.
- Elapidae: cobra, coral snake, mamba
- Boidae: boa, python
- Colubridae: grass snakes, corn snakes
- Viperidae: vipers, rattlesnakes
Snakes with triangular heads are more ______ than snakes with round heads
Snakes are _______, which means that they rely on their environmental temperature to maintain body temperature.
The integument of snakes are made up of scutes. What are the 3 types of scutes found on the snake and what are their shapes?
- Dorsal scutes: smaller
- Ventral scutes: transversly shaped to protect belly
What factors might contribute to dysecdysis?
- Presence on mites
- Incorrect humidity
Why would you not handle a snake when it is shedding?
The epidermal scale in the eyes are cloudy which decreases eyesight
What covers the eye of a snake?
What is missing in the snake ear that is found in most other animals?
Tympanic membrane and external openings
What type of sounds can a snakes hear? What structure allows this and how does it work?
Low frequency sounds due to the columella attached to the quadrate bone. The soundwaves are detected through the ground.
Snakes contain special infared receptors called sensory pits. What are the 3 subgroups and where are the pits located in each? Which ones are venomous, and which are not?
- Pit vipes: pits b/w eyes & nares = venomous
- Pythons & boas: labial pits on upper & lower lip = nonvenomous
- Coral snakes: no pits = venomous
What type of teeth do snakes contain?
What is the structure of teeth in nonvenomous snake?
- 6 rows
- 2 on palate
- 2 on maxilla
- 2 on mandible
What is the structure of the teeth in a venomous snake?
- Fangs replace maxillary teeth
- 2 rows on palate
- 2 rows on madible
What organ is found on the snakes tongue that is used for chemoreception?
Vomeronasal sense is important in what?
Predation & chemoreception
What will happen to a snake if it were to lose it's tongue?
- Multicellular gland will no longer secrete mucous
What is located between the nasal and oral cavities and is significantly important for respiration in birds and reptiles?
What is the bone in the snake skull that allows the jaw to vertically spread when eating?
Snakes do not have a thoracic or pelvic girdle, but boidaes may have ________ and _______.
Spurs and vestigial pelvic girdles
The mandible is joined by a highly elastic ligament which allows for what?
Spreading of the mandibles to accomodate for prey size
What is the range of vertebrae found in snakes and where are the ribs located on the vertebrae?
150 - 400 vertebrae with ribs cranial to the cloaca
What type of body cavity lines the snakes organs? What are they missing that most animals contain?
Coelomic cavity and no diaphragm
How many chambers does the snake heart contain?
What gland does the snake contain that is present throughout their life and is located lateral and cranial to the thyroid?
What is the renal portal system?
Blood in the back half of the body filters directly through the kidneys without circulating through the heart first
The snake does not contain a diaphragm. How does it breath?
The intercostal muscles and rib movement
Describe the anatomy of the snake respiratory system.
- The trachea does not bifurcate and leads to a right lung, which is composed of a vascularized anterior portion and a posterior portion made of air sacs for air regulation
- Left lung may or may not be present and is vestigial.
What part of the digestive system of a snake controls food boluses entering the intestines?
What are the basic characteristics of the snake digestive system?
- Muscular esophagus
- Stomach small, not C-shaped & located on left
- Contain a large liver
Boids are the only snakes with a ______ in their digestive system.
What is snake urine composed of?
Do snakes have a bladder? Explain.
No, the ureters enter into the urodeum of the cloaca.
Where are the male and female snake gonads located and how many do they have?
Intrabdominal, each has 2
How are snakes sexed?
- Cloacal probe (male: 8 - 20 scales, females: 2 - 4 scales)
- Dimorphism: color & appearance
How long can the female snake store sperm in the oviduct?
Months to years
Define: oviparous, viviparous, oviviparous and parthenogenic
- Oviparous: egg laying & external hatching
- Viviparous: live birth
- Oviviparous: eggs hatch internally & birth appears to be live
- Parthenogenic: asexual reproduction
What are the four layer of the amniotic egg? What is the purpose of each?
- Chorion: produces shell
- Amnion: contains embryo
- Allantois: contains wastes
- Yolk sac: water source containing albumin and nutrients
What is the term for yolk production? What is required for this to occur?
- Must have anough fat stored for this to occur