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What is a grasshopper? A grasshopper is an arthropod. It has Jointed appendages A segmented body An exoskeleton
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Dissection of a Grasshopper What is a grasshopper? A grasshopper
is an arthropod. It has
Jointed appendages A segmented body An exoskeleton Grasshopper
Facts: Country: Worldwide Habitat: meadows, fields, and hedges
Length: up to 3 in. (8cm) but mostly 5/8 -1 1/8 in. (15-30
mm)Weight: almost nothing Closest relative: katydid and cricket Why
dissect a grasshopper?
To identify the external and internal anatomy of the grasshopper To
practice basic dissection skills Explore this site to learn more
about grasshoppers.
Get ready to learn more as we dissect a grasshopper! Step One
Identify the materials you will need for your dissection.
Dissection Tray Hand lens Materials, continued Ruler Scalpel
Scissors Eye dropper
Dissection pins Forceps (tweezers) Materials, continued Gloves
Goggles And a grasshopper! Study the external parts of the
grasshopper Step Two: Identify the Head Thorax Abdomen
Notice also the eyes, antennae, legs and wings Skeleton The
grasshopper has a hard exoskeleton.That means its skeleton is
located on the outside of its body, not internally like ours.This
skeleton is made of chitin, a carbohydrate. The head A Frontal View
of the head The compound eye The grasshopperhas two compound eyes
that are made up of hundreds of individual eyelets. Observe the
antennae The grasshopper's head has two antennae that are able to
feel and smell what is nearby. The mouth The mouthparts are a set
of movable jaws that let the grasshopper chomp its way through
grass blades. The mouth Labrum - the broad upper lip Hypopharynx -
the tongue
Mandibles - two heavy blackish jaws with teeth along the inner
margin. The mandibles move up and down. Maxillae - two smaller jaws
that move side to side Labium - the lower lip Palp - maxillary and
labial palps are sensory appendages The thorax The legs Using huge
hind legs, the grasshopper makes gigantic leaps into the air. Long
legs are an advantage for jumping, because they increase the
distance over which the jumper can push off the ground The legs,
continued When a grasshopper jumps, it first crouches down, there
is then a short delay, and then off it goes. Back leg- knee The
leg, continued The two rear legs are specialized and strengthened
for jumping, while the front two pairs are used only for walking on
the ground The Wings The two pairs of grasshopper wings differ in
shape, structure, and function.The hind pair are responsible for
flight. Close up of the wings After its spring-assisted takeoff, it
can unfurl its two pairs of wings and continue flying with them.
The abdomen The hind region of the grasshoppers body, the abdomen,
consists of 11 segments. The Abdomen The abdomen is built up of a
series of upper plates known as 'tergites' and lower plates known
as 'sternites.It is held together by a tough yet stretchable
membrane Determine the sex of your grasshopper Close up Female Male
Reproductive organs Female Reproductive organs Male Task Draw a
diagram of the external parts of the grasshopper.Label at least the
following: Head Thorax Abdomen Compound eye Antennae Wings
(forewing and hindwing) Mouth Step Three:Measure Measure Be sure to
record the length of your grasshopper.
Measure the grasshopper from the tip of the head to the end of the
abdomen. We will collect these measurements at the end of the
dissection lab and compare! Step Four: The Dissection begins:
Position the grasshopper dorsal side up Carefully remove the
protective sheath from the scalpel. Hold the grasshopper firmly.
Cut along the dorsal surface of the thorax and abdomen Gently pull
the exoskeleton aside You may wish to use the dissection pins to
make viewing easier. Using a hand lens, identify as many of the
internal organs as possible Digestive System These are the parts of
the digestive system :
Mouth Esophagus Crop Stomach Intestine Chewed food is stored in the
crop, digested in the stomach, and absorbed in the intestine.
Observe the digestive system A little closer The crop, gizzard and
digestive caecae
The digestive caecae produce enzymes which aid in digestion
Respiratory System You will probably NOT be able to see the small
holes. on the side of their bodies without your hand lens. These
holes are called spiracles, each hole leads to a large tube called
a trachea. The large tubes divide into small tubes that branch out
to all the cells of the body. This system of tubes carries oxygen
to the cells and takes away the carbon dioxide. Respiratory System
Do you see anything in your grasshopper that resembles a lung?
Respiratory System The grasshopper does not have a lung.How then
does it breathe? Air enters the spiracles and as the abdomen
expands and contracts, fresh air moves in and used air moves out.
The air enters the cells directly and is not transferred to the
blood- thats why their blood is yellow, not red- it contains no
hemoglobin! Circulatory System The grasshoppers circulatory system
is open- that means that it does have a heart, but the heart is
more of a muscular tube that collects the blood and forces it to
the front of the body. The blood freely flows throughout the
grasshopper The Nervous System The grasshopper's brain is located
between its eyes, above the esophagus. Cool fact The grasshopper
does not use its brain to walk or jump!It does that without a
brain. The brain is used to control the mouth and to send sensory
information to the rest of the body. Excretory System There are a
number of tubules between the large intestine and the stomach.The
outer end enters into the body cavity and takes in the wastes.The
wastes are carried into the large intestine and out through the
anus. Task Draw a diagram of the internal organs you
identified.Include at least the following: Intestines Crop
Reproductive organs Be sure to: Properly dispose of your
grasshopper
Remove the dissection pins. Pick up the grasshopper and any organs
that you may have removed.Discard them into the plastic bag
provided. Be sure to dump the remaining liquid in the jar as this
is the last dissection. Sanitize scalpels and pins, rulers and hand
lenses and trays.Return them to the kit. Wipe down lab tables and
discard gloves. users.rcn.com/.../ BiologyPages/I/Insects.html
~wjh/jumping/legwrk.htm about/grasshopper.html io.uwinnipeg.ca/
~simmons/hopper4.htm grasshopper/ghparts.htm