Biology 3B
Exam 2 Study Guide
I’ve tried to include everything that was covered; however, there may be some inadvertent omissions. Anything covered
in lecture will be fair game. If you’re not sure, just ask (me) or email.
Chapter 32
Essay Questions:
 Be able to diagram early embryonic development from zygote to the gastrula stage including the germ layers (be
able to use the following terms: cleavage, blastula, gastulation, metamorphosis)
 Understand the hypothesis for the origin of animal from flagellated protist
 What’s the role of homeoboxes and HOX genes in animal diversity
 Be able to diagram and understand the advantages of body plans for Acoelomate, Pseudocoelomate, and
Coelomate
 Compare and contrast the early development in protostomes and deuterstomes (look at figure 32.9 for some
guidance)
Chapter 33
Essay Questions:
 Know important characteristics in each phylum including echinoderms and crustaceans (ie Cnidaria – diploblastic,
nematocysts)
 Define the following: ostia, osculum, spongocoel, radial canals, choanocytes and amoebocytes. Briefly describe
asconoid, syconoid and leuconoid body types of sponges.
 What are the characteristics of an endoparasite?
 Know the various types of parasites discussed in lecture and lab. Be prepared to discuss how they’re acquired,
disease they cause, where they’re found geographically and within its host (intermediate and final); and any main
disease conditions (Ascaris, Necator, Trichinella, Wuchereria, Enterobius, Dracunculus, Fasciola, Taenia,
Schistosoma, Clonorchis, Onchocera, Diroflilaria).
 Briefly describe asconoid, syconoid and leuconoid body types of sponges.
 What are major characteristics of Molluscs that distinguish it from other phyla? Members of this large and diverse
phylum have impacted humans in many ways. Explain this statement.
 What are important features distinguishing features of arthropods?
 Briefly explain the difference between complete and incomplete metamorphosis. Include a brief discussion about
ecdysis, ecdysone, juvenile hormone and prothoracotropic hormone and how they’re involved in metamorphosis.
 Onychophorans have been regarded by some biologists as a “missing link” between annelids and arthropods.
What evidence supports this hypothesis? What evidence suggests that onychophorans form a distinct phylum?
 How are the five classes of echinoderms similar and different from each other?
 You will have some taxonomy (inverts and verts) questions down to class (infraclass for
mammals) for inverts the written fill-in portion, for example:
.
The greatest contribution to biology by members in this phylum is metamerism. All
member possess setae, a ventral and dorsal nerve cord with an anterior "brain," a dorsal
"heart" for moving blood in their closed circulatory system.
.
Name the subclass for the egg laying mammals
Chapter 34
Essay Questions:
 Name the five hallmark anatomical characteristics of the phylum Chordata and explain their function and what
they’ve become in you.
 List four adaptations discussed in lecture that have guided vertebrate evolution, and explain how each has
contributed to the success of vertebrates.
 In 1928, Walter Garstang hypothesized that tunicates resemble the ancestral stock of the vertebrates. Explain
this hypothesis.
 Briefly discuss how the 4 adaptations discussed in lecture that has guided vertebrate evolution
 Distinguish between ostracoderms and placoderms. What important evolutionary advances did each contribute to
vertebrate evolution? What are conodonts?
 Explain how bony fish differ from sharks and rays in the following systems or features: skeleton, scales,
buoyancy, respiration, reproduction.
 Give the geographical locations of the three surviving genera of lungfishes and explain how they differ in their
ability to survive out of water. Which of the three is least specialized?
 Understand the hypothesis for the evolution of vertebrate jaws.

Differentiate between Oviparous, Ovoviviparous & Viviparous. Place all of the classes in the subphylum
Vertebrata in the three modes of reproduction. Remember, some groups maybe used more than once:
Petromyzontida, Chondrichthyes, Amphibia, Lepidosauria, Aves, Mammalia, Crocodilia, & Testudines.
 Compared with aquatic habitats, terrestrial habitats offer both advantages and problems for an animal making a
transition from water to land. We discussed how the changes in oxygen concentration, density of the medium,
temperature and the availability of water might have influenced the early evolution of tetrapods. So, the question
on the exam may be…select one of the aforementioned issues and discuss: what the problems they faced and
what were the solution or solutions terrestrial vertebrates evolved to deal with changes.
 Compare and contrast ecothermic and endothermic organisms. What is meant by poikilothermic and
homeotherm? How would these terms relate to the first set of terms? (Ch 40 stuff as discussed in the invasion of
land)
 Compare and contrast physiological and behavior thermoregulation. Ch 40 stuff as discussed in the invasion of
land). Shivering vs non-shivering thermogenesis
 What’s is a rete and do they work to cool or heat up an organism?
 Compare the heart structure and the circulation pattern of fish, amphibians, reptiles (noncrocodilian),
birds and mammals.
 What are the four extraembryonic membranes of the amniotic egg of a bird or a reptile and what is the function of
each? What is the fate of the four extraembyonic membranes of the amniotic egg in placental mammals?
 Describe ways in which reptiles are more functionally or structurally suited for terrestriality than the amphibians.
 Not as an essay questions, but for multiple guess: I would know what is meant by a “kinetic” skull and what
benefits does it confer? How are snakes able to eat such large prey? How is possible for snakes (and
crocodilians) breathe when their mouths are full of food (this includes us also)?
 Describe how a snake moves by lateral undulation (serpentine locomotion). Why might this form of locomotion be
inefficient on an unstable surface (such as sand) or surfaces lacking irregularities? What forms of locomotion
would work for a snake under these conditions?
 Why is the tuatara of special interest to biologists? Where would you have to go to see one in its natural habitat?
 Know the differences between anapsid, diapsid & synapsid skulls
 How might nest temperature affect egg development in turtles? In crocodilians (high  males, low temp 
females)
 Know the reptilian & avian characteristics for Archeopteryx.
 What are the advantages of seasonal migration for birds? Describe the different navigational resources birds may
use in long-distance migration.
 Define the terms precocial and altricial as they relate to birds.
 Offer some examples of how human activities have affected bird populations (increases, decreases, expansion of
range, etc.).
 Briefly describe the following types of feathers: contour, flight, down, filoplum and powderdown and their typical
function. Draw a typical contour feature and label its parts: quill, vane, barbs and barbules.
 Describe how air flows through a birds respiratory system and how it’s adapted for meeting the high metabolic
demands of flight.
 Define diphyodont and heterodont and explain why both terms apply to mammalian dentition. Are there mammals
that are homodont? Discuss the four types of dentition found in mammals and include their function.
 What do the terms Theria, Metatheria, Eutheria, Monotremata and Marsupailia mean? List at least two mammals
that are grouped under each taxon.
 Most mammals today are nocturnal. Briefly explain why they are and the characteristics that allowed them to be
successful nocturnally. We will discuss 12 points.
 Briefly discuss the formation the neural tube formation and the fate of the neural crest cells.
 Be prepared to discuss the five avenues of heat exchange (Ch 40 stuff as discussed in the invasion of land)
 Anything on the invasion of land will be fair game, if I’ve left something off
Non essay stuff – more to come
 Know the general characteristics for the vertebrate classes. What gave rise to amphibians, reptiles,
birds and mammals?
Chapter 40 – animal form and function
 4 types of tissues and subcategories (types of cells found and functions)
 Homeostasis – positive & negative feedback mechanisms (sensors, processor, effectors)
 Thermoregulation – Tb vs Ta for endo/ectotherm, conformer vs regulator, TNZ, lower/upper critical, lower/upper
lethal, endotherm vs ectotherm, homeotherm vs poikilotherm, avenues of heat loss and gain (convection,
radiation, conduction, evaporation), piloerection, ptiloerection, insulation, counter-current heat exchange,
behavioral vs physiological responses, BMR vs SMR vs RMR, calories vs kilocalories vs Calorie, how does size
affect MR, why mass specific MR?, types of torpor – why? Daily vs seasonal, hibernation vs aestivation
 Some of these have may have been covered when I discussed the invasion of land.
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factual recall (do you know the information)
conceptual understanding
application (can you apply the information that you learn or are you just a vomit test taker still in high
school?)
 the last two questions are what student call “tricky” questions because they just memorized
the material as opposed to understanding the material
If you need help, please ask!!! Don’t wait until the last minute!!!