Download Class Agnatha - Mayfield City Schools

Class Agnatha
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Classification
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Superclass: Agnatha
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Sub Class: ______________________________________ = hagfish
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Sub Class: _______________________________________=lamprey
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Order = Petromyzontiformes
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Petromyzon marinus
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The sea lamprey. Originally described by Linnaeus back in 1758. This species is native to much of the coastal
areas in the Northern Atlantic.
Petromyzon = ____________________________________________
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This is the creature that got into the Great Lakes and has caused havoc. ?
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Hagfish = Sub Class Myxini
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_______________________________________
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___________________________________ or predators feeding off dead or dying fish and sea life.
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Senses: _____________________________, but good senses of_____________________ and smell.
Notable Facts about Hagfish
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Excellent Adaptation: Its body fluid are in _______________________________________________
with sea water. This makes it easier to maintain water balance and deal with some waste.
Can tie itself in a ________________________to more securely attach itself to its prey.
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Can generate enormous amounts of____________________________.
Video Clip:
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Lampreys = Sub class Cephalaspidomorphi
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_____________________________________________________.
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Marine species are _____________________________________
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Which means they live in the sea/ocean and migrate up freshwater streams to spawn. Like
salmon.
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Around ½ of lamprey species are _________________________ and the others as adults do not feed
and their digestive systems reduces in size and becomes non-functional.
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Characteristics: Anatomy and Structure of Lamprey
o Only ___________________ fins. No ________________________ appendages.
o Long eel like shape.
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The Mouth!!
o Most notable _________________________________ characteristic.
o A_____________________________mouth, that is used for _____________________ and rasping.
o Mouth contains 11 to 12 rows of circular ___________________ teeth enclosed by an oral hood.
This teeth hood arrangement is called _______________________________.
o The ___________________________________gland in the mouth releases an
_______________________________________ that helps the flow of blood when it attaches to a
fish.
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Digestive Tract and Parasitic Feeding
o The superior design of the buccal funnel allows it to attach to fish and get a good seal, which helps
maintain correct pressure for blood flow.
o Prefers, blood and body fluids, but some flesh etc. also is consumed.
o Under lab conditions feeding lasts 76 hours. With young adults up to 200!!
o No__________________________________only an intestinal tract.
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Skeleton System
o Has _________________________________________ present as an adult.
o It is slightly modified in that it has _________________________________________ and thus are
put with the subphylum vertebrata.
o __________________________________________ skeleton with a cranium, a brain case.
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Circulatory and Excretory
o ____________chambered heart. Of interest with hagfish they have 3 additional aortic arches, but
with a low pressure circulatory system.
o Mesonephric Kidney: “__________________________” kidney (out of 3) filters waste materials
o Excretion of waste through __________________________________________ and possibly gills.
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Nervous System
o Differentiated ________________________________
o 8-12 pairs of _____________________________ nerves
o Sight more developed than hagfish, and will use it to locate prey/host near the surface or shallow
water.
o Has a ____________________________________ located on top of head. A light sensitive organ
which senses diurnal changes.
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SEX and Reproduction
o Hagfish are ____________________________________________ and have gonads for both sexes.
Will only be male or female but can change from year to year.
o Lamprey: ___________________________________
o __________________________________ fertilization
o Females produce on average 230,000 eggs which are adhesive and non-buoyant.
o Great Lakes average is 60,000 eggs. (r or K strategist?)