Transcript Explorers Presentation_Squid Dissection and Project_201015x

Squid Dissection
Explorers Education Programme: www.explorers.ie
Basic Information
• Squid are part of the cephalopod family, which
include octopus and cuttlefish.
• They are invertebrates, which mean they have
no backbone. Approximately 97% of all the
living creatures on the planet are invertebrate
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Swimming
• Swimming: They swim by taking in water under
their mantle (this is the main part of their body
above their head) and pushing it out through
their siphon, which is a funnel shaped opening on
the back of the head.
• It is similar to how a jet ski works. They change
direction by turning their head (changing the
direction of the siphon) and using their fins,
which are located at the top of the mantle.
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Feeding
• Feeding: They catch their food by extending
their two long tentacles to trap small
creatures. They use their eight short arms to
hold their prey in place.
• The arms and tentacles have suction cups
located on them to help squid do this. Their
mouth is called a beak, and it is situated in the
centre of the arms and tentacles.
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Protection
• They project themselves by camouflage (changing
colour to blend in) and by squirting ink.
• They change their colour using special cells (that
look like spots) on the surface of their body called
chromatophores.
• These cells work like a flower opening and closing
its petals. When the petals are open, you can see
the entire colour, when they are closed you see
none. The cells can open and close in this way
four times each second, resulting in squid being
able to change colour faster than a chameleon.
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Vision and Size
• Vision: They have two eyes, which are large
for their overall body size. The colossal squid,
mentioned below, has an eye around the size
of a basketball.
• The largest types of squid in the world include
the colossal squid and the giant squid, and
they can grow up to 13m.
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Where are these external features?
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Internal Features
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Internal Organs
• Gonad: This is the squids reproductive organ. If the
squid is female that this will have clear, jelly-like eggs in
it. If it is a male then it will have white stringy-like milt.
• Gills: Squid have two long feathery gills for removing
oxygen from the water.
• Ink Sac: This organ stores the ink that the squid
produces in it body. If the squid squirts out ink it must
make more to replace it. Squid ink is not poisonous. It
is used in cooking to make dishes such as black pasta. It
can also be used as a dye for colouring items. Cuttlefish
ink, also known as Sepia was used to colour
photographs for many years.
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More on the inside!
• Heart: The Squid has one main heart (kind of
peachy in colour), located in-between the top of
the two gills and two small gill hearts (white in
colour), one located at the top of each gill. The
gill hearts can be hard to locate.
• Female squid also have a Nidamental gland. This
is a large white organ, which sits on top of the
other internal organs and is used in coating the
eggs before they are released into the water. This
can be removed gently to expose the other
organs when carrying out the dissection.
Explorers Education Programme: www.explorers.ie
Squid Pen or Gladii
• Squid, have an internal structure that looks
like a pen, which acts as a backbone within
the squid.
• It supports the squids muscles and organs.
• Its flexibility allows for its method of
swimming.
• It is made from Chitin.
• It can be removed from the squid and cleaned
to study it further in class.
Explorers Education Programme: www.explorers.ie
Squid Project
• Science - Living Things: Animal life in the ocean
• Working scientifically complete a project about squid, giant
squid or a colossal squid. Questions could include:
- What types of squid is your project about?
- What does the squid look like?
- What size are (in comparison to humans, whales etc) is the
squid?
- What ocean do they typically live in and where?
- Where was the largest squid found in the world?
- What myths, stories and real tales are recorded about squid
(e.g. historical evidence)
Design your own squid and tell a tale
for a scientific display
Images by Dr John Joyce