Sharks

murmerlastΠολεοδομικά Έργα

16 Νοε 2013 (πριν από 3 χρόνια και 8 μήνες)

90 εμφανίσεις

Sharks

Classification


Kingdom Animalia


Phylum _____________


Class
_____________


Subclass
_____________

»
Superorder
_____________



Known as “__________” until the 16
th

century


Name “shark” may have come from the
Yucatec Maya

Evolution


Earliest sharks evolved
_________
years ago


Today


_________

species


Smallest


dwarf lanternshark (7 in)


Largest


whale shark (largest fish


40 ft)

Skeleton


No bones


Use cartilage and connective tissue


Strong , but ___ the __________ of bone



Reduces weight


saves energy


Cartilage may be
_____________


“bone
-
like”


No functional
_____________


Must stay in water

Jaw


Covered in a layer of
_____________


Complex ________ surface


Single tile in a mosiac


Tiny hexagonal plates


Crystal blocks of
_____________


Most sharks have one layer of tesserae


Great white sharks


up to
_____________


Teeth


Embedded into _____ rather than the jaw


Arranged into _____ rows of ______ teeth


Continuously replaced


Gums “
_____________
” them to the front


Can shed
____________

teeth in a lifetime


Tooth characteristics determined by _______


Very important to fossil record


all that
remains



Tooth Anatomy

Fins


Supported by unsegmented _____ composed
of
_____________

Tail (Caudal) Fins


____ different designs found in sharks


Shapes evolved due to different _________
and _____________


All are _____________ in design


Top is _______ than the
bottom

Buoyancy


____ swim bladder


Large
_____________


Up to _____ of body mass


Contain _____________


Oil that is
_____________

that water


Sharks hunted for this oil


Put in capsules as a health supplement


Used in vaccines


Also available from plant sources

Respiration


Oxygen removed as water passes through the
mouth and over the
_____________


Process known as _____________


Most sharks can pump water over their
gills while at rest


Some cannot (obligate ram ventilators)


Gills _______ covered (as with most fish)

Circulation


Sharks have a ______
chambered heart

_________________


Most sharks are
_________________
(cold
blooded)


Body temp is that of the environment


Family Lamnidae sharks can raise their body
temp higher than the water temp (includes
mako and great white)


_____________


Strip of red muscle in center of body attached
to the __________________ (miraculous net)

Rete Mirabile


Uses
___________________

flow design

_____________


Living in salt water


Large production of _____


Shark’s tissues ________________ (in balance
with) the sea water


So, few sharks can live in fresh water


Bull sharks can change their kidney function to
____________________________

Senses


Smell


Very keen ________ sense


Can detect __________
of blood in sea water


Even greater attraction
to chemicals found in
_________ of organisms


Leads sharks to
sewage outfalls

Olfactory Bulbs (in pink)

Senses


Sight


Eyes similar to most vertebrates


Well adapted to the dark marine
environment


Use a _______________ (bright tapestry)


Reflects light back through the retina
to increase amount of useable light


Humans do the same (_____________
in a photo)


Can
_____________

and
_____________

their
pupils

Senses


Sight


Sharks have eyelids, but
_____________


Water cleanses eyes


Use
__________________________


_______________ that moves over eyes to
protect them during ___________ on prey

Senses


Hearing


May be able to hear prey ____________ away


Hard to test


Small opening on each side of the head


Leads to the inner ear


Sense _________________
among the water molecules

Senses


Hearing


_____________

system


System of _________ within the lateral line


Runs the length of the body


___________ expose water to the system


Contains ____________ cells with hair
-
like projections


Also helps with ________ and movement


Lateralis System

Senses


_____________


Sharks can detect electromagnetic fields
produced by all living organisms


Sharks have the _____________ electrical
sensitivity of any organism


Helps them find prey (even under the sand)


Use ____________________________


Electrorecptor organs


Hundreds to thousands per shark

Pores (on a tiger shark)

Senses


Electroreception


Ocean currents travel through the magnetic
field of the earth


Creates electric fields


May allow sharks to
_____________

the
world’s oceans


Allows sharks to detect
_____________


__________________