Bio1331 Animals - Evolution - Ecdysozoans (Lecture Five)

Complete the following sentence:One of the key features of the ecdysozoans is the ___________, a tough, non-cellular, secreted body covering.

Complete the following sentence:For an ecdysozoan to grow, the cuticle must be _____ and replaced with a larger one.

Approximately when did moulting evolve?

• A.

  >500 million years ago

• B.

  >5 million years ago

• C.

  >5 billion years ago

• D.

  >500 thousand years ago

True or False?Ecdysozoans had a single common ancestor.

• A.

  True

• B.

  False

Complete the following sentence:________ is a term meaning the moulting of the cuticle to enable growth.

The Nematodes are a clade of Ecdysozoans.Tick everything below that this group of organisms are/have.

• A.

  Bilaterally symmetrical

• B.

  Radially symmetrical

• C.

  Triploblastic

• D.

  Diploblastic

• E.

  Segmented

• F.

  Unsegmented

• G.

  Thick, multi-layered cuticle

• H.

  Thinly layered cuticle

• I.

  Pseudocoelomate

• J.

  Acoelomate

• K.

  Coelomate

The second clade of Ecdysozoans taught in the lectures are the most dominant animals on the Earth, accounting for at least 75% of described species and found in nearly all habitats on the planet.Name this species.

Please fill answer below_______

Complete the following sentence:________ were an early arthropod, with simple and repetitive body segmentation and appendages.

The substance that composes the exoskeleton is leathery in its pure form, but becomes harder when encrusted with calcium carbonate.It is found within the endocuticle of the exoskeleton.Name this substance.

Complete the following sentence:Some arthropod joints contain a substance called _______, which stores energy on compression and releases it efficiently, allowing them to jump.

True or False?Butterflies were the first insects to fly.

• A.

  True

• B.

  False

Complete the following:Insects have many adaptations to gas exchange.One of these adaptions is the _________, external openings on the thorax and abdomen. These can be closed to regulate water loss.