Animal life cycles Knowledge-Based Download PDF

Questions

1. 1.

   In the life cycle of a parasitic animal, which term describes the host organism in which the parasite reaches sexual maturity and carries out sexual reproduction?

   • A) Definitive host
   • B) Intermediate host
   • C) Paratenic host
   • D) Reservoir host
2. 2.

   In the life cycle of many cnidarians, such as jellyfish, which body form represents the free-swimming stage that carries out sexual reproduction?

   • A) Planula
   • B) Polyp
   • C) Ephyra
   • D) Medusa
3. 3.

   In which type of animal life cycle does the organism bypass a distinct larval stage entirely, hatching or being born as a miniature version of the adult that simply increases in size and matures?

   • A) Direct development
   • B) Complete metamorphosis
   • C) Incomplete metamorphosis
   • D) Alternation of generations
4. 4.

   During the life cycle of a frog, which anatomical transformation occurs as the aquatic larva matures into an adult?

   • A) Development of a rigid chitinous exoskeleton that is periodically shed through molting
   • B) Replacement of functional lungs by branched external gills to facilitate underwater diving
   • C) Secretion of a calcified, cleidoic shell around developing body tissues to prevent desiccation
   • D) Resorption of the aquatic tail and gills accompanied by the emergence of limbs and functional lungs
5. 5.

   Which stage of the life cycle is present in organisms undergoing complete metamorphosis, but is entirely absent in those undergoing incomplete metamorphosis?

   • A) Egg
   • B) Adult
   • C) Nymph
   • D) Pupa