Discuss the terms oviparous, ovoviviparous, and viviparous. What would be some advantages and
disadvantages of each?
Oviparous—animals that lay eggs
Ovoviviparous—animals that retain eggs within their bodies until they hatch, and then give birth to live young
Viviparous—animals 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.
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In which mode does cycle asynchrony most commonly occur?
a. Volume ventilation. b. Pressure ventilation. c. CPAP. d. No mode is more susceptible.
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a. Increase the O2 flow rate. b. Decrease the treadmill speed. c. Decrease the treadmill incline. d. Terminate the procedure at once.
When cultured as a significant isolate from a genital culture, which of the following organisms does not routinely require susceptibility testing?
A) Candida albicans B) Anaerobic gram-negative rods C) Staphylococcus aureus D) Enterobacteriaceae