Practice Exam for BIO 311. Exam II

 

1.  Often various species of sponge reproduce at the same time.  When sponges sexually reproduce:                                                                                             a.  some embryonic development is external (and embryos are found in gelatinous
string that cling to the surface of the parent sponge)                                               b.  by fertilizing themselves since they are hermaphroditic                                   c.  sperm enter female sponges and enter the osculum to locate the oocytes/eggs
(internal fertilization)                                                                                             d.  all of the above are true

 

2.      If two species of coral were living next to each other on a coral reef, what would be the most likely outcome?                                                                               a.  nothing would happen; corals do not have an immunity system                                                                                                              b.  the more aggressive species would smother the other by growing at a faster rate                                                                                                                                     c.  the more aggressive species would detect the other and produce filaments to
attack the other species                                                                                     d.  the less aggressive species would go dormant for a period of time

 

3.      In some species of Cnidarians we find that a polyp form cycles with a medusa stage when sexually reproducing.  In other species, only one form remains and reproduces sexually.  Which is the PRIMITIVE condition?                              a.  alternating between polyp and medusa                                                             b.  remaining only in polyp stage                                                                          c.  remaining only in medusa stage

 

4.      Cnidaria and Ctenophora were formerly placed together in a single phylum known as Coelenterata because in part these animals shared:                                         a.  cnidocytes                                                                                                   b.  radial symmetry                                                                                             c.  complete gut                                                                                                d.  true nervous system

 

5.      Suspension feeders, such as sponges:                                                                  a.  cannot select which type of food they ingest – it is a passive process                                                                                                             b.  expend little energy compared to filter feeders when adapting this feeding strategy                                                                                                               c.  must remain motionless and sessile in order to feed                                         d.  need to worry about expelling waste through their gastrovascular cavity

 

6.      Water (and potentially food) moves through the body of a sponge at different rates based on the animal’s architecture.  Water flow velocity is lowest over the choanoderm chambers (with collar cells) because:                                             a.  its cross-sectional diameter is larger then the other vessels and openings (e.g.
osculum and ostia)                                                                                               b.  amoeboid cells in the choanocyte chambers can slow the exit of water from the
chambers by changing shape and position                                                             c.  both a and b are true                                                                                      d.  neither a nor b are true

 

7.      Which of the following is true regarding ecdysis?                                                a.  the new exoskeleton/cuticle is not made until the old one is shed                                                                                                                   b.  the animal’s exoskeleton begins to break open at the most posterior end of the animal                                                                                                                                 c.  after it is secreted, the new exoskeleton/cuticle hardens from the most inner
 layer (endocuticle) to the most outer layer (epicuticle)                                                                                                         d.  it is under hormonal and neural control

 

8.      Insects and other arthropods that have an exoskeleton are limited in how large in size they can grow because:                                                                                a.  the exoskeleton is hollow and it has greater resistance to bending than a solid
 rod of the same cross-sectional area                                                                  b.  as an insect grows larger in size, the thickness of the exoskeleton increases                                                                                                           c.  a large insect has an exoskeleton that is stronger and more resistant to stresses
from impact than a small insect                                                                          d.  they live on land and produce uric acid as a waste product

 

9.      Because Cnidarians, such as jellyfish, do not have true respiratory systems, they must rely on diffuse of gases in and out of their bodies.  This should place a strict limitation on body size, yet some species can reach great lengths and sizes.  What allows for the increase in size?                                                                                                                          a.  presence of a third layer of cells (triploblastic animal)                                                                                                                b.  the mesogloea thickens and the cells in it can help transport gases and waste                                                                                                               c.  the gastrovascular cavity is small in size and expands the length of the animal,
           and diffusion only occurs across this cavity                                              d.  spicules are placed in the skeleton to aid in support of the large size

 

10.  What do most people today consider an individual sponge?                                                                                                               a.  every choanocyte chamber represents an individual                                                                                                          b.  each osculum and its associated cells constitute an individual                                                                                                             c.  any and all sponge material bounded by a continuous outer cellular covering
           (which may include many oscula) constitutes an individual                          d.  all cells that have the same genome (genetic material) is an individual
regardless of whether the cells are found on the same structure

 

11.  The cnida, or harpooning-like threads, that are discharged from the cnidocyte of Cnidarians is secreted by the:                                                                              a.  golgi body of the cnidocyte                                                                            b.  nucleus of the cnidocyte                                                                                  c.  mitochondria of the cnidocyte                                                                          d.  lysosomes of the cnidocyte

 

12.  What is TRUE regarding nematocysts?                                                                 a.  they are all barbed and penetrate prey, none wrap around prey                                                                                                                  b.  they are filled with a fluid, which contains toxins                                                 c.  they can be used multiple times (and thus can be “recycled”)                         d.  all of the above are true

 

13.  Coral reefs are limited in distribution because they require:                                                                                                               a.  water temperatures of no less than an average minimum of  20°C                                                                                                               b.  minimum sunlight penetration in the water column                                           c.  high levels of sediments in the water                                                                 d.  a certain species of coral-building fish

 

14.  Corals are important reef builders and obtain their nutrients:                                                                                                             a.  primarily from the symbiotic algae that live inside them                                     b.  by releasing nematocysts and spirocysts into their prey                                                                                                                      c.  by using a mucus net to their advantage to help trap prey                               d.  all of the above are true

 

15.  Some species of Cnidarians can be found in polymorphic colonies.  What does this mean?  I.e. what is the design of such a colony? 

 

16.  Identify one reason why humans are economically interested in sponges. 

 

17. Suspension feeders have dealt with the trick of removing food particles from the local environment by the use of five fundamentally different mechanisms.  One of these methods is to modify limbs with rows of feather-like setae adapted for generation water currents across parts of the body and removing selected particulate matter form it.  Identify and explain one other method.  Be sure to explain how this method works thoroughly (i.e. don’t just list a method – explain it).