Dearolf
BIOL 220
PHYLUM CNIDARIA QUESTIONS
Class Scyphozoa
1. The name of the polyp stage in the life cycle of Aurelia is the ___________________________.
2. This stage undergoes an unique form of ASEXUAL reproduction called
____________________________, which creates saucerlike buds.
3. After undergoing this process, the polyp is now called a _____________________.
4. The saucerlike buds are called ____________________________.
5. One of the saucerlike buds is in the micrograph below. Label this stage of the Aurelia
life cycle with the following structures: gastric pouch, lappet, and rhopalium.
6. The gonads of mature Aurelia form in their _______________________________ (2 words)
and arise from ectoderm/endoderm (circle one).
7. In comparison, the gonads of hydrozoan medusae like Obelia form in association
with their _______________________________________ (2 words) and arise from
ectoderm/endoderm (circle one).
8. In Aurelia, fertilization is external/internal (circle one), and the zygotes may
develop out in the ocean or in the female’s _______________________________ (2 words).
9. The zygote of Aurelia develops into a ciliated _________________________________ (2 words),
which divides meiotically/mitotically (circle one) to produce the polyp stage.
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Dearolf
BIOL 220
Class Anthozoa
1. A distinctive feature of all anthozoans is the division of their large gastrovascular
cavities into smaller spaces by inward extensions of the body wall called
_____________________________.
2. Members of the Subclass Hexacorallia possess __________ (number) pairs of complete
inward extensions of the body wall.
3. The complete inward extensions of the body wall are called
_____________________________ (2 words).
4. The members of the Order Actiniaria possess a ciliated groove at one or both ends of
their mouths called a _________________________________.
5. The purpose of this structure is to create a ___________________________________ (2 words)
directed into the pharynx.
6. Incomplete extensions of the body wall are also found in the gastrovascular cavities
of actiniarians. The purpose of these extensions is to increase the
________________________________________ (2 words) of the cavities.
7. The free edge of each incomplete extension of the body wall forms a sinuous cord
called a __________________________________ (2 words), which contains
_________________________________ and gland cells for digestion.
8. The sinuous cords within the gastrovascular cavities of anemones are similar to
structures found within the gastrovascular cavities of scyphozoan jellyfish, which
are called ________________________________________ (2 words).
9. The lining of the sinuous cords of anemones and the similar structures found in
scyphozoan jellyfish arise from ectoderm/endoderm (circle one).
10. In the members of Order Actiniaria, gonads form on the margins of the
____________________. Thus, they arise from ectoderm/endoderm (circle one).
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Dearolf
BIOL 220
11. A cross-section of Metridium is in the micrograph below. Label the structures using
the terms from questions 3, 4, and 7 (2 word term), and the following terms:
epidermis, the TWO types of incomplete extensions of the body wall, gastrodermis,
gastrovascular cavity, mesoglea, and retractor muscles.
12. Corals are in the same Subclass as anemones, but they are in Order
____________________________.
13. One distinctive feature of corals is the _________________________________ (2 words) that
the polyps secrete and live in.
14. Tube anemones and thorny corals are members of the Subclass
_______________________________________.
15. A distinctive feature of organisms in this Subclass is the possession of
_____________________________________ (2 words) within their gastrovascular cavities.
16. Tube anemones are colonial/solitary (circle one), while thorny corals are
colonial/solitary (circle one).
17. Sea fans, sea pens, and sea pansies are examples of organisms in the Subclass
_____________________________________.
18. These soft corals have _______________ (number) unpaired
____________________________________ (2 words) within their gastrovascular cavities.
19. Soft corals are colonial/solitary (circle one).
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