Animal Morphology and Classification

These flashcards cover key concepts in animal morphology and classification.

Animals are classified as __________ organisms that are multicellular, heterotrophic, and eukaryotic.

Animals

When comparing animals to other eukaryotic organisms, they are characterized by the absence of a __________ and photosynthetic machinery.

cell wall

The nine major animal phyla include Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Arthropoda, Echinodermata, and __________.

Chordata

In bilateral symmetry, one cutting plane creates distinct __________ mirror-image halves.

left and right

Invertebrates are animals that do not possess a __________ or spinal column.

dorsal bone

The term used to describe when an animal exhibits segments that are structurally different is __________.

tagmatization

The body symmetry type associated with concentration of nervous tissues and sense organs in the head is called __________ symmetry.

bilateral

The main function of the osculum in sponges is to act as the primary exit for __________ from the sponge's central cavity.

filtered water, waste products, and gametes

Phylum Cnidaria is characterized by its __________ symmetry and sac-like gastrovascular cavity.

radial

Jellyfish exhibit two stages in their life cycle: the polyp stage and the __________ stage.

medusa

The class of flatworms that is free-living and possesses eyespots is called __________.

Turbellaria

The __________ are parasitic flatworms with no digestive tract that absorb food through their body walls.

Cestoda

Nematodes are recognized for their __________ bodies that taper at both ends.

round and slender

Annelids exhibit a __________ digestive system and a closed circulatory system.

complete

The muscular foot of mollusks is used for __________.

locomotion

Class __________ includes intelligent marine predators such as octopuses and squids.

Cephalopoda

The animal phylum with the largest number of species is __________.

Arthropoda

In sea stars of class Asteroidea, the mouth is located at the center of the __________ surface.

oral

Sea cucumbers belong to the class __________ and are characterized by their elongated and soft body.

Holothuroidea

Echinoderms have an endoskeleton composed of __________ plates.

calcareous

Mammals are considered the most __________ and specialized class of Chordates.

advanced