4 - Chordate and Vertebrate Characteristics Origins

A set of flashcards to help review key concepts from Zoology 224 related to embryology, chordate characteristics, and vertebrate origins.

What are the five unique features that all chordates share?

1. Notochord 2. Dorsal hollow nerve cord 3. Pharyngeal slits 4. Post-anal tail 5. Subpharyngeal gland or endostyle.

What developmental feature differentiates vertebrates from other chordates?

Neural crest cells.

What is the primary cavity called that is produced within the mesoderm?

Coelom.

What type of symmetry do vertebrates exhibit?

Bilateral symmetry.

What is the notochord and its significance?

An elongate, fibrous, fluid-filled rod that serves as the main support for the body.

What term refers to the method of coelom formation in vertebrates?

Enterocoely.

In which animal group are pharyngeal slits primarily used for filter feeding?

Cephalochordates and urochordates.

What structure do pharyngeal slits develop into in vertebrates?

Gill openings.

What do ectodermal placodes contribute to?

They form sensory structures including those of the inner ear, nasal cavity, and parts of the eye.

What feature allows vertebrates to have a tripartite brain?

The anterior portion of the dorsal hollow nerve cord develops into the brain.

What is the developmental significance of the three primary germ layers?

They give rise to specific tissues and organs in the body.

What unique feature is mainly derived from the ectoderm in vertebrates?

Neural crest cells is the unique feature that is mainly derived.

What does the term eumetazoa refer to?

A clade comprising all major animal groups except sponges.

What are the two subdivisions of Bilateria?

Protostomia and Deuterostomia.

What are vertebrates considered within the phylum Chordata?

Subphylum Vertebrata.

What is the primary role of the endoderm layer?

It becomes the lining of the digestive and respiratory tubes.

What type of cleavage do deuterostomes exhibit?

Radial cleavage.

What embryonic layer forms muscle, bone, and connective tissue?

Mesoderm.

In vertebrate embryology, what do the neural crest cells give rise to?

Many structures including cartilage, bone, and parts of the sensory system.

What is the function of the thyroid gland in vertebrates?

It is involved in metabolizing iodine.

What critical evolutionary feature is derived from the notochord in vertebrates?

The vertebral column.

What are myomeres?

Block-like muscle segments along the body of vertebrates.

What is the significance of the taxon Metaspriggina in vertebrate evolution?

It is thought to be the oldest known vertebrate.

What are cranial nerves?

Nerves associated with the brain and at least partially encased within the cranium.

Which two organisms provide early evidence for the evolution of vertebrates?

Pikaia and Metaspriggina.

What distinguishes the vertebrate heart from those of other chordates?

It is muscular and forms part of a closed circulatory system.

Which layer becomes the central nervous system in vertebrates?

Dorsal hollow nerve cord.

What is the main difference between protostomes and deuterostomes in embryonic development?

The blastopore becomes the mouth in protostomes and the anus in deuterostomes.

What developmental stage involves the differentiation of basic germ layers?

Gastrulation.

How does the vertebrate structure differ from that of protochordates?

Vertebrates have unique structures such as neural crest and ectodermal placodes.

What type of skeleton do vertebrates have?

Endoskeleton made of cartilage or bone.

What is the role of intervertebral disks in vertebrates?

They act as compression pads between vertebrae.

What classification includes both jawed vertebrates and their ancestors?

Gnathostomata.

What does the term 'chordate' imply about certain characteristics of vertebrates?

They possess a notochord and other chordate features at some point in development.

What does the term 'amnion' refer to in vertebrate development?

A membrane that encloses the embryo in many vertebrates.

What evolutionary significance do hagfish have in relation to vertebrates?

They are considered the most primitive living vertebrates.

What are the two main sources of the integument in vertebrates?

Epidermis from ectodermal tissue and dermis from mesodermal tissue.

Why are nephrons significant in the vertebrate excretory system?

They are the fundamental units of the excretory system unique to vertebrates.

What are the primary functions of the post-anal tail in chordates?

Locomotion and balance.