Download BIOL212test2keyMAY2012

Experience (Test) 2 – Animal Diversity, Digestion, Circulation & Evolution
BIOL212
9 May 2012
Name: Key
34.) The distinction between sponges and other animal phyla is based mainly (primarily) on the absence
(versus the presence of)
a. a body cavity
*d. true tissues
b. a complete digestive tract
e. mesoderm
c. a circulatory system
35.) Acoelomates are characterized by
a. the absence of a brain
b. the absence of mesoderm
c. deuterostome development
d. a coelom that is not completely lined with mesoderm
e. *a solid body without a cavity surrounding internal organs
36.) Which of the following combinations of phylum and description is incorrect?
a. Echinodermata – bilateral symmetry as a larva, coelom present
b. Nematoda – roundworms, pseudoceolomate
c. Cnidaria – radial symmetry, polyp and medusa body forms
d. Platyhelminthes – flatworms, gastrovascular cavity, acoelomate
e. *Porifera – gastrovascular cavity, coelom present
37.) Which of the following would increase the rate of heat exchange between an animal and its
environment?
a. feathers or fur
b. vasoconstriction
c. *wind blowing across the body surface
d. countercurrent heat exchanger
e. blubber or fat layer
38.) Vertebrates and tunicates share
a.) jaws adapted for feeding.
b.) a high degree of cephalization.
c.) the formation of structures from the neural crest.
d.) an endoskeleton that includes a skull.
*e.) a notochord and a dorsal, hollow nerve cord.
39.) All 20 amino acids are needed to make animal proteins. Why are not all of them essential to animal
diets? (2 points)
Ten of the amino acids CANNOT BE MADE by humans (and many other animals) so
they are essential. The other ten can be synthesized if they are not present in the diet.
40.) If a zoo animal eating ample food shows signs of malnutrition, how might a researcher determine
which nutrient is lacking in its diet? (3 points)
Add individual supplements to the diet until the signs of malnutrition disappear. (At
least some credit was given for “tests” – however there are not adequate tests for many, since it is as
quick and cheaper to determine with supplements!)
41.) Distinguish the overall structure of a gastrovascular cavity from an alimentary canal. (4 points)
Gastrovascular cavity: single opening (“mouth/anus”), no differentiation, also “circulatory”. Vs.
Alimentary Canal: “one way” mouth – tube – anus. Tube is (at least to some degree) differentiated.
I.e. esophagus, stomach, intestines, with more differentiation in many classes.
3
Experience (Test) 2 – Animal Diversity, Digestion, Circulation & Evolution
BIOL212
9 May 2012
42.) Three chambered hearts with incomplete septa were once viewed as being less adapted to
circulatory function than mammalian hearts. What advantage of such hearts did this viewpoint not
consider? (You should have read this in the text.)
Found in amphibian & reptilian species: when submerged, where there is gas
exchange across the skin, but lungs do not function, much of the blood supply bypasses the
lungs, so O2 accumulation is maximized.
43.) Explain why blood in the pulmonary veins has a higher O2 concentration than blood in the venae
cavae, which are also veins. (2 points)
All veins return blood to the heart (vs. arteries that take blood away from the heart.)
The venae cavae return deoxygenated blood from the body to the heart. The pulmonary veins,
while returning blood to the heart, do so from the lungs where the blood has just been oxygenated.
(This is one of those “interconnectedness” examples: ventilation & circulatory systems
interacting.)
44.) What is the primary reason for (cause of) the low velocity of blood flow through capillaries? (2 points)
While the cross section of individual capillaries is very small, there are so many
capillaries that the TOTAL CROSS SECTION is extremely large: hence the same volume of blood
has moved from a “small pipe” to a “large pipe”, so the pressure drops!
45.) What advantage is there for low velocity of blood flow through the capillaries? (2 points)
Since gas, nutrient and waste exchange occurs in the capillaries, the lower velocity
maximizes these fucntions.
46.) If a professor were to begin a lecture on animal phylogeny by saying, “We are all worms”, in this
context what would the professor mean? (2 points)
From “worms” on “up”, all organisms are “tubes within tubes”. (Some credit given
for “common ancestry” type answers.)
47.) Among eumetazoans, embryos may be diploblastic or triploblastic. What is the difference? (In
other words “define”.) 2 points (extra point for defining eumetazoan.)
Diploblastic: 2 germ layers: ectoderm and endoderm
Triploblastic: 3 germ layers: add mesoderm (in between)
Eumetazoan: (animals possessing) true tissues
48.) What are the three major characteristics common to all animals? (3 points)
Heterotrophic
Eukaryotic
Multicellular
49.) What is the fourth characteristic that more clearly distinguishes animals from fungi and plants?
Fungi (heterotrophic) & plants (autotrophic) are eukaryotic, have cell walls & most
are multicellular. While botanists may disagree (sort of) neither have “true tissues”!
50.) Explain how the polyp and medusa forms of cnidarians are both similar and different. (5 points)
(You may use a diagram, to make it clear!)
They are in almost all respects the same: two layers of cells that make a sac: a
gastovascular cavity. Polyps are sessile with the single opening “up”. Medusae are flattened
opening “down” free floating versions of polyps.
4
Experience (Test) 2 – Animal Diversity, Digestion, Circulation & Evolution
BIOL212
9 May 2012
51.) Describe the structure and function of the stinging cells for which cnidarians are named. (3 + 1 points)
Cnidocytes contain cnidae, capsule-like organelles that explode outward.
Specialized cnidae called nematocysts (+1) contain a stinging thread that penetrates prey.
52.) Explain how tapeworms can survive without a coelom, a mouth, a digestive system or an excretory
system! (3 points)
Since tapeworms LIVE IN THE DIGESTIVE TRACT of their hosts, already digested
nutrients are brought to them and wastes will be carried away. (A coelom would reduce this
efficiency.)
53.) How do nematode and annelid body plans differ? (How are they similar?) 2 points
Like the “We are all worms” question, both are tubs within tubes and “very worm
like”. Annelids are segmented & coelomate while nematodes are not and psuedocoelomate.
54.) Describe two adaptations that have enabled insects to thrive on land. 3 points
Exoskeleton (chitinous) prevents water loss
Wings (flight) allowing easy widespread dispersal or
Tracheal system that allows for efficient gas exchange
55.) What is a choanocyte and where are they found? (2 points)
Flagellated “collar cells” lining the interior of the spongocoel (so found in sponges)
56.) Choose one mammalian organ system and list the main (primary) components and main (primary)
functions. (5 points) multiple possibilities (see Fig. 40.1, p. 855) e.g.
Digestive system:
Mouth, pharynx, esophagus, stomach, intestines, liver, pancreas, anus
57.) If a mouse and a small lizard of the same mass (both at rest) were placed in experimental chambers
under identical environmental conditions, which animal would consume oxygen at a higher rate? Explain.
(3 points)
The mouse is an endothermic homoeotherm (produces its own body heat)
The lizard is an ectothermic poikilotherm (body temperature varies with external
environment.) Hence the mouse’s metabolism requires more oxygen.
These are verbatim from a “pop quiz”:
58.) Which animal phylum is considered “basal”? Porifera (Sponges)
59.) Which phylum is believed to include the most species? Arthropoda (which includes insects)
more than a million species!
60.) Name a phylum and list its defining characteristics (5 points): various p. 695
E.g. Chordata: notochord
Hollow dorsal nerve cord
Post anal tail (at some point in development)
Pharyngeal slits
61.) What is a coelom? (I.e. define coelom)
Fully mesoderm lined body cavity (that contains, surrounds, the internal organs)
5
Experience (Test) 2 – Animal Diversity, Digestion, Circulation & Evolution
BIOL212
9 May 2012
62.) What are the three germ (cell) layers that give rise to all the tissue types? (3 points)
ectoderm, mesoderm, endoderm
Bonus:
63.) Unlike eutherians, both monotremes and marsupials
a.) lack nipples.
*b.) have some embryonic development outside the uterus.
c.) lay eggs.
d.) are found in Australia and Africa.
e.) include only insectivores and herbivores.
6