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Diversity in Dentition
For the Cow, the Human and the Dog you must explain the teeth and jaw structure
including the facial muscles and how these features relate to what it eats.
You must be specific and fully explain the structures and their function. You then need
to discuss how these structures relate to it’s lifestyle in terms of nutrition.
Your presentation must include:
Detailed diagrams of each (drawn diagrams are fine and can be scanned easily) with
labelled structures
An explanation of each of the structures/muscles and their function for EACH animal
An essay type discussion as to how these structures are designed to help it survive.
This presentation must be in your own words and uploaded onto your website when
completed. Feel free to use any software package you feel necessary. You can even
use publisher and make it as a poster. Then it can go on the net and on the wall!
Remember: Diversity means DIFFERENCES so make sure you are focussing on
different structures – how are they unique?
Teeth Structure
Muscle Structure
Human Mastication
Mastication in humans is controlled through the four main muscles of
mastication. These are the lateral pterygoid, medial pterygoid,
temporalis, and masseter muscles. These allow the jaw to move
fowards and backwards, up and down, and side to side.
Human teeth resemble the herbivore structure more than the
carnivore one. Each row has 2 pairs of insisors followed by a pair of
canines, followed by several pairs of molars and premolars.
These adaptions allow for the human hebivoric nature, as the
canines help to tear the meat, the molars help grind plant and
vegatable matter, and the insisors are used for snipping things.
Teeth Structure
Muscle Structure
Cow Mastication
The structure of teeth in the cow is specifically designed for
eating grass. The horny pad with the row of incisors
underneath help the cow crop the grass, so it can get it into
the mouth. From then there is a row of flat molars and
premolars. These are designed to slide across each other,
thus breaking down the grass, to be stored in the cow’s first
stomach, until it is chewed up again later, in the shade. (Cud)
The predominate jaw muscles in the cow are the masseter
and the pterygoid muscles. These used together allow the
cow to perform the side to side motion of it’s jaw which
grinds up the grass it eats.
Teeth Structure
Muscle Structure
Canine Mastication
The dog’s teeth are designed for it’s carnivorous lifestyle. The four main
canine teeth, and most of the others (molar and premolars) are sharp and
designed for ripping and shredding the meat the dog eats. They curve
inwards a little to help the dog hold it’s prey in place.
The dog’s main jaw muscle is the Temporalis muscle. This muscle is so big
that it takes up most of the space in the jaw structure. As this muscle moves
the jaw only up and down, the dog is to a large part unable to move it’s jaw
back and forwards, or side to side.
The jaw and tooth function of the dog allows it to easily eat meat. Which is
fantastic, as it is a carnivore. The up and down movement allows it to tear at
the meat, with it’s jagged teeth helping to rip the meat.
(This is not canine
mastication)
Pictures Used:
http://www.smallpawsrescue.org/pup3/teethrosalyn.jpg
whyfiles.org/shorties/147tooth/
http://whyfiles.org/shorties/147tooth/images/teeth.jpg
http://www.tpub.com/content/medical/14274/img/14274_49_1.jpg
http://www.wonderquest.com/2006-09-05-cow-jaw.jpg
http://upload.wikimedia.org/wikibooks/en/c/c3/Anatomy_and_ph
ysiology_of_animals_Dogs_skull.jpg
http://www.parks.sa.gov.au/publish/groups/public/@parks/@upp
ersoutheast/documents/all/005454.gif
http://www.parks.sa.gov.au/publish/groups/public/@parks/@upp
ersoutheast/documents/all/005453.gif
Teeth Structure
Muscle Structure
http://www.myspacecomedy.com/images/funny/dog-mouth.jpg