All GRE Subject Test: Biology Resources
Example Questions
Example Question #2 : Speciation And Phylogenetics
Which of the following is false of the phylum chordata?
They have a coelom
They are protostomes
They have bilateral symmetry
They have a notochord at some point in their development
They are protostomes
All chordates are deuterostomes, not protostomes. During early development, the formation of the blastopore leads to the growth of the digestive tract. In protostomes, the blastopore develops into the mouth, while in deuterostomes it becomes the anus.
All chordates have a notochord during development, which eventually gives rise to the nervous system. Chordates also have a coelom, or fluid filled cavity, somewhere within the body and they all exhibit bilateral symmetry.
Example Question #1 : Speciation And Phylogenetics
Which of the following is not necessary for designation as a chordate?
I. A notochord
II. Vertebrae
III. A post-anal tail
IV. Gill arches
V. A dorsal, tubular nervous system
V
I
II
IV
III
II
Chordates must have, at some point in their embryogenesis, all features except vertebrae. Although the vast majority of chordates are vertebrates, Amphioxus has only a notochord. This primitive organism never develops vertebrae. Man has gill arches, and remnants of these are seen in certain congenital malformations. The notochordal remnants can give rise to the tumor known as a chordoma. The brain has ventricles (it is tubular) and it is certainly dorsal. Finally, human tail persists in about one per million live births.
Example Question #2 : Speciation And Phylogenetics
Which of the following statements about chordates is true?
They lack a coelom
All chordates are vertebrates
They are protostomes
Their anus forms from the blastopore
Their anus forms from the blastopore
The phylum chordata has a few key characteristics. They are deuterostomes, meaning that the anus arises from the blastopore. They have a coelom that arises from the mesoderm during development, and at some point they have a tail, pharyngeal slits, and a notochord.
Vertebrata is a subphylum of chordata, so not all chordates are vertebrates (though all vertebrates are chordates).
Example Question #1 : Identifying Animals
Which of the following organelles is/are mainly present in animal cells?
I. Peroxisome
II. Centrioles
III. Flagella
II only
I and III
III only
I only
II and III
II only
Centrioles are generally only found in animal cells, but have been found in a variety of eukaryotes. There are a small subset of plants that do contain centrioles. Some plant cells have flagella and peroxisomes.
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