Describe the four common features all marine mammals share. What will be an ideal response?
(1) Their streamlined body shape with limbs adapted for swimming makes an aquatic
lifestyle possible. Drag is reduced by a slippery skin or hair covering.
(2) They generate internal body heat from a high metabolic rate and conserve this heat with
layers of insulating fat and, in some cases, fur. Their large size gives them a favorable
surface-to-volume ratio; with less surface area per unit of volume, they lose less heat through
the skin.
(3) The respiratory system is modified to collect and retain large quantities of oxygen. The
biochemistry of blood and muscle is optimized for the retention of oxygen during deep,
prolonged dives.
(4) A number of osmotic adaptations free marine mammals from any requirement for
freshwater. Minimal intake of seawater, coupled with the ability of their kidneys to excrete a
concentrated and highly saline urine, permit them to meet their water needs with the
metabolic water derived from the oxidation of food.
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What tools do fishermen now employ to locate schools of fish?
a. Scouting vessels b. Satellite sensors c. Ariel photography d. All of these choices
Which of the following is an example of an active remote sensing device?
A) LIDAR B) video camera C) Landsat D) film E) infrared sensor
The major ionic constituents of sea salt are normally found to ________.
A. behave as conservative materials B. have a constant ratio of each constituent to each other C. have the same ratio to each other even when diluted by rainwater D. All of these are correct. E. None of these is correct.
A worm would stand a poor chance of being fossilized because ________.
a. worms have no hard parts b. worms have been rare during the geologic past c. worms contain no carbon-14