-
What does the term Herps refer to?
Reptiles and amphibians
-
Do amphibians have scales like reptiles?
No
-
The class reptalia includes what animals?
Snakes, lizards, chelonians, crocodiles
-
What order and suborder does the snake belong to?
Squamata, serpentes
-
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
Dangerous
-
Snakes are _______, which means that they rely on their environmental temperature to maintain body temperature.
Poikilothermic/ectothermic
-
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
- Malnutrition
- Dermatitis
- Trauma
-
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?
Epidermal scale
-
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?
Polyphyodontic
-
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?
Jacobson's organ
-
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
- Infection
- Death
-
What is located between the nasal and oral cavities and is significantly important for respiration in birds and reptiles?
Choanal slit
-
What is the bone in the snake skull that allows the jaw to vertically spread when eating?
Quadrate bone
-
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?
3
-
What gland does the snake contain that is present throughout their life and is located lateral and cranial to the thyroid?
Thymus gland
-
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?
Pyloric valve
-
What are the basic characteristics of the snake digestive system?
- Linear
- Muscular esophagus
- Stomach small, not C-shaped & located on left
- Contain a large liver
- Gallbladder
- Cloaca
-
Boids are the only snakes with a ______ in their digestive system.
Cecum
-
What is snake urine composed of?
Uric acid
-
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?
- Vitellogenesis
- Must have anough fat stored for this to occur
|
|
