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Student Resources
Mammalia-Workbook QuestionsHow does countercurrent
blood flow in the extremities minimize cooling of the body core of a
mammal? (p.
136)
In a wading bird,
the water where their feet are may be considerably colder than the core
body temperature of the animal. The arteries extending down the leg are
positioned next to the veins that bring the blood back up to the body, and
as blood flows down, it warms the blood coming up. The result is that
blood returning to the body is at its normal temperature while blood in
the extremities is closer to the temperature of the water that surrounds
it.
For what is
each type of tooth modified?
(p. 137)
Incisors are
modified for cutting; canines for piercing and puncturing prey; premolars
(part of the first set of teeth) for grinding; and the molars (part of the
second set of teeth), like the premolars, for grinding.
What is the
role of the hepatic portal system?
(p. 138)
The hepatic portal system is the part of the circulatory system found between the digestive system and the liver. As food is digested, nutrients pass into the hepatic portal system and blood carries them to the liver where they may be further metabolized. Along with nutrients, are potential toxins detoxified by the liver before they have a chance to circulate through the rest of the blood supply.
Protozoa || Porifera ||
Cnidaria ||
Platyhelminthes || Nematoda || Annelida ||
Mollusca || Arthropoda
Echinodermata || Chordate Origins ||
Jawed Fishes || Amphibia ||
Mammalia
