Invertebrates Quiz

Invertebrates

• Approximately 95% of animal species are estimated to be invertebrates.
• The Latin word 'vertabra' means "joint" or "turned".
• The term 'invertebrate' is derived from the prefix 'in-' meaning "not" or "without", and the concept of turning, expressed in the root 'verto', referring to the vertebral column.

Characteristics of Invertebrates

• The primary trait that distinguishes invertebrates from vertebrates is the absence of a vertebral column.
• Invertebrates do not have a vertebral column, which is a characteristic of vertebrates.

Taxonomy of Invertebrates

• The term 'invertebrate' is used as a convenience for animals that are not members of Vertebrata.
• 'Invertebrata' has very little circumscriptional significance except within the taxon Animalia.
• A valid taxon within Animalia is Vertebrata, which includes animals with a vertebral column.
• Arthropoda is a sister chordate subphylum to Vertebrata.
• A taxon in the same way that Arthropoda and Vertebrata do is a phylum.

Types of Invertebrates

• A major invertebrate group that includes insects, crustaceans, and arachnids is Arthropoda.
• Arthropoda has the largest number of described extant species among all invertebrate groups.

Cladogram Construction

• The presence or absence of the vertebral column should logically follow the presence or absence of a notochord in constructing a cladogram.