ch3-2

Funnel water through the muscular pharynx where food particles are trapped in mucus.

10 centimeters or longer and several years old.

No more than two years.

<p>1920s to the 1950s.</p> Signup and view all the answers

<p>Reduction of economically important fish species like lake trout, burbot, and lake whitefish.</p> Signup and view all the answers

<p>Other Great Lakes of North America.</p> Signup and view all the answers

<p>The large rocks rim the upstream pit and downstream mound, creating eddies and oxygenating the water in the nest.</p> Signup and view all the answers

<p>The male lamprey wraps around the female, fertilizing the eggs as she lays them.</p> Signup and view all the answers

<p>Adult lampreys die after breeding once.</p> Signup and view all the answers

<p>Ammocoetes are tiny, 6- to 10-millimeter-long wormlike organisms with a large oral hood and nonfunctional eyes.</p> Signup and view all the answers

<p>The ammocoetes are carried downstream by currents to backwaters and quiet banks where they burrow into soft mud or sand.</p> Signup and view all the answers

<p>The sand and smaller stones downstream of the pit create eddies that oxygenate the water in the nest.</p> Signup and view all the answers

<p>Some more derived types of ostracoderms are more closely related to gnathostomes (jawed vertebrates) than others.</p> Signup and view all the answers

<p>Ostracoderms had dermal bone and gnathostome-like features such as a cerebellum in the hindbrain and an olfactory tract connecting the olfactory bulb with the forebrain.</p> Signup and view all the answers

<p>The interpretation changed considerably as new understanding emerged about how ostracoderms are related to each other and to living vertebrates.</p> Signup and view all the answers

<p>Most ostracoderms are characterized by the presence of dermal bone, usually in the form of an extensive armored shell or carapace.</p> Signup and view all the answers

<p>Ostracoderms ranged in length from about 10 centimeters to more than 50 centimeters.</p> Signup and view all the answers

<p>In ostracoderms, the olfactory bulbs are placed more anteriorly and linked to the head via the olfactory tract, unlike in living agnathans.</p> Signup and view all the answers

<p>Presence of jaws that bear teeth and two sets of paired fins or limbs</p> Signup and view all the answers

<p>Silurian</p> Signup and view all the answers

<p>Improvements in locomotor and predatory abilities, sensory and circulatory systems</p> Signup and view all the answers

<p>Living jawed vertebrates show evidence of a second Hox duplication event</p> Signup and view all the answers

<p>Extinct ostracoderm taxa</p> Signup and view all the answers

<p>Major radiation of jawed vertebrates commenced</p> Signup and view all the answers

<p>Acts as an elastic reservoir that smoothes out the pulsatile nature of blood flow.</p> Signup and view all the answers

<p>The cartilage in gnathostomes is different and more specialized.</p> Signup and view all the answers

<p>Gonads have specialized ducts leading to the cloaca.</p> Signup and view all the answers

<p>Fins act as hydrofoils, applying pressure to the water, creating thrust in the opposite direction.</p> Signup and view all the answers

<p>Increases the area of the tail, providing more thrust during propulsion.</p> Signup and view all the answers

<p>To maintain balance and control movement efficiently.</p> Signup and view all the answers