Vertebrate Anatomy Exam 1 Flashcards | Quizlet

In vertebrates, what do the first and second embryonic openings form into?

The first opening forms into the anus and the second forms into the mouth.

Into which subphyla is the phylum Chordata broken?

Urochordata, Cephalochordata, Vertebra

Which subphylum do Amphioxis, Lancelets, and Branchiostoma belong to?

Cephalochordata

Which subphylum do Tunicates and Sea squirts belong to?

Urochordata

What are the five traits that all chordates share?

Notochord, dorsal hollow nerve cord, pharyngeal pouches, endostyle, post anal tail

What does the dorsal hollow nerve cord evolve into in vertebrates?

Spinal cord

How many pharyngeal outpocketings are present in vertebrates?

$$7$$

What did Richard Owen develop that suggests species are all variations on a theme?

Archetype

What is the Plane of Equivalency?

All organisms have been evolving for the same time with varying levels of change

How did Richard Owen define homology?

Same organ in different animals under every variety of form and function

How did Richard Owen define analogy?

A character in one animal that has the same function as a character in a different animal

What is ontogeny?

The life of a single organism from fertilization to death

What are the stages of a vertebrate's life?

Fertilization, development, neonate, juvenile, adult, senescence, death

What is cladogenesis?

Any branching event where much phenotypic evolution occurs, creating a new clade

What is anagenesis?

Phenotypic evolution among one lineage without any branching

Which evolutionary models correspond to cladogenesis and anagenesis?

Cladogenesis is akin to punctuated equilibrium, and anagenesis is akin to gradualism

What is the difference between a synapomorphy and a symplesiomorphy?

A synapomorphy is a derived trait unique to one group, whereas a symplesiomorphy is a shared ancestral character state

What are the sequential stages of vertebrate embryo development?

Morula, blastula, gastrula, neurula, organogenesis, birth

At which stages are vertebrate embryos totipotent?

At the $2$ and $4$ cell stages

What is the archenteron?

Early embryonic gut tube

What do somites contribute to in vertebrate development?

Skeleton, muscles, dermis

Which cells build endochondral bone and which absorb it?

Osteoblasts build bone, while osteoclasts absorb bone

What occurs during bone calcification?

Calcium phosphate precipitates out of blood and bonds to collagen fibers

What is the blood vessel hole in each osteon called?

Haversian canal