Answer to Question 1Oviparousanimals that lay eggs
Ovoviviparousanimal s that retain eggs within their bodies until they hatch, and then give birth to live young
Viviparousanimals that retain the young within their bodies in a preplacental sac
Oviparous reptiles lay their eggs in nest cavities in the soil. The eggs are covered and then left untended.
When the young hatch, they are on their own, relying on inherited instincts for survival.
Snakes may be oviparous, ovoviviparous, or viviparous. Most are oviparous. Snakes that are ovoviviparous
retain the eggs within their bodies until they hatch, and then they give birth to the young. The young receive
no nourishment from the female, only the nourishment contained in the egg.
In a few species, the young are retained in a preplacental-type sac, which allows for some exchange of
oxygen and nutrients. This is referred to as viviparous.
Some species of ovoviviparous and viviparous snakes protect their newly hatched young from predators.
Crocodilian females will stay within the vicinity of their nests to guard against predators. When she hears
the sounds of the young coming from the eggs, the female will begin to dig the top of the nest away so the
young can emerge.
Answer to Question 2Turtles and tortoises do not molt their thick epidermal skin. Each year, a new epidermal scale is formed
beneath the old one. This allows for the expanding growth of the animal. These epidermal scales are called
scutes.
Scutes of the plastron are the gular, humeral, pectoral, abdominal, femoral, and anal scutes. Scutes of the
carapace are the nuchal, supracaudal, marginals, centrals, and costals. Refer to Figure 202 in the text.