Chapter 44 Flashcards
The majority of all known animal species are:
insects
Cnidarians have _____ symmetry
radal
Ecdysozoans include insects and make up more than half of all known animal species.
true
Which of the following statements is false regarding chondrichthyes?
Chondrichthyes can (typically) only tolerate low levels of urea.
A phylogenetic tree is:
a diagram of the evolutionary relationships among different species.
Which of the following is not true of sponges?
Sponges are among the most primitive organisms to have developed reproductive organs.
The group Lophotrochozoa includes
annelid worms and mollusks.
Which of the following are cartilaginous fish?
sharks and rays
The period of time during which an “explosion” of fossilized animals with bilateral symmetry are first found is the
Cambrian.
The development of wings on a fly, a moth, and a bird are ____ because they developed independently as adaptations to perform the common function of flying.
analogous
Placozoans, which were first discovered in an aquarium, are by far the most diverse of the eumetazoans, with approximately 10,000 documented species.
false
Imagine that scientists have discovered annelid life on a new planet. Remarkably, these worms are large in size, lack mouths, and appear to form symbioses with certain bacterial species. These worms most resemble ______________ on Earth.
vestimentiferan worms
All amniotes lay eggs, as exemplified by reptiles, birds, and monotremes.
false
The colonization of land by animals
may have taken place independently by a variety of species descended from aquatic environments.
A protostome is distinguished by a(n):
blastopore that becomes a mouth.
A researcher has just discovered a new marine organism that appears very similar to jellyfish. However, on closer inspection, this organism possesses both a mouth and anal pore, and a single set of tentacles. This animal is most likely a
comb-jelly.
All echinoderms (sea stars and sea urchins) have:
a water vascular system and five-fold symmetry.
Which of the following is not a characteristic of vertebrates?
an open circulatory system
Which of the following is not true regarding the history of life on Earth?
The rise of more complex organisms such as eukaryotes has resulted in a reduction in diversity of more “primitive” organisms such as bacteria.
Bilaterians are distinguished by:
mirror symmetry that results in a distinct head and tail and one plane of symmetry.
Which of the following are cnidarians?
jellyfish and sea anemones
Which of the following statements is true of chelicerates?
Chelicerates, unlike insects and crustaceans, do not actually have antennae.
Vertebrates may have an external skeletal system.
false
Unique characters evolve over long periods of time. The time that a particular character arose can be estimated by determining
shared presence of the character in descendants of the population in which the character first arose.
A researcher has just discovered a new marine organism that appears very similar to jellyfish. However, on closer inspection, this organism possesses both a mouth and anal pore, and a single set of tentacles. This animal is most likely a
comb-jelly.
Crustaceans:
have a hard external skeleton composed of a polysaccharide commonly known as chitin.
Which of the following is true regarding hagfish and lampreys?
They are vertebrates
Modern day birds are most closely related to which of the following?
dinosaurs
(Please choose from the lettered responses below.) Phylogenetic trees help us understand:
1-the genetic relationships among a species.
2- the evolutionary relationships among a species.
3- the relationships of symmetry among related species.
4- the level of complexity among related species.
2 and 4
A researcher is culturing cells in a petri dish. After a few weeks, she notices that these cells have formed a “sheet,” with junctions visible between individual cells. Which of the following statements is not true regarding these cultured cells?
These cells have formed mesoglea.
Chordates include:
tunicates and vertebrates.
If you have ever watched a television show on sharks, you may have noticed that certain fish attach themselves to sharks (and are considered to be parasites). Interestingly, these fish lack definitive jaws or mandibles. These parasitic fish are most likely:
lampreys.
Microorganisms dominated Earth’s ecosystems for most of the planet’s history.
true
_____ are not helpful for reconstructing evolutionary relationships because they do not show the evolutionary development of characters among groups.
Analogies
What feature of animals enabled them to function in so many ways that they have been able to diversify in ways that plants, fungi, algae, and protozoans have not?
Organ systems
What structure would you expect to find in every type of mollusk (i.e., gastropods, cephalopods, and bivalves)?
mantle
Which of the following is not a cell or structure found in sponges?
gastric cavity
Which of the following is not a component of some sponge skeletons?
cartilage
A deuterostome is distinguished by a(n):
blastopore that becomes an anus.
Which of the following statements is true of sponges?
External fertilization occurs in all species of sponge; sponge eggs are fertilized externally in seawater.
Like cnidarians, many sponges produce toxin-generating nematocysts. These cells typically line the pores of sponges.
The choanocytes of sponges and choanoflagellates share no morphological similarities.
Like comb-jellies, sponges possess both a mouth and an anal pore; however, the anal pore is distinctly smaller than the mouth.
None of these statements are true regarding sponges.
Regarding the gastric cavity of the cnidarians, which of the following is true?
Digestive enzymes allow the consumption of prey such as fish whole.
Ctenopores (comb jellies):
have a separate mouth and anal pore, unlike cnidarians.
If you’ve ever read any stories about Sherlock Holmes, you may remember that he once solved a mystery where a man died due to injuries sustained from a lion’s mane jellyfish. Apparently, the victim encountered this free-floating jellyfish in a pool of water, was stung, and died suddenly. From this information, you can deduce that the victim encountered the jellyfish in what form?
medusa
All lophotrochozoa have:
bilateral symmetry and complex organs.
Triploblastic organisms give rise to ___ germ layers, which include _______.
three; ectoderm, mesoderm, and endoderm
Which of the following is not true of sponges?
Sponges are among the most primitive organisms to have developed reproductive organs.
____ are helpful for reconstructing evolutionary relationships because they show the evolutionary development of characters among groups.
Homologies
Due to the production of chitin, arthropods occupy a unique position on the tree of life. These organisms are much more closely related to fungi (which also produce chitin) compared to either cnidarians or lophotrochozoans.
false
Which of the following is false regarding cnidarians?
Cnidarians have a separate opening for the anus and the mouth.
What feature of animals enabled them to function in so many ways that they have been able to diversify in ways that plants, fungi, algae, and protozoans have not?
Organ systems
Insects:
have a respiratory system including spiracles connecting to a trachea.
Linnaeus sorted animals into groups based on body plans. Today, these groupings are called:
phyla.
