Grasshopper Dissection

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Grasshopper Dissection
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Arthropods
Arthropods make up the largest phylum of
animals in the animal kingdom. Arthropod means
jointed foot. All arthropods have jointed
appendages. Arthropods also have segmented
bodies and an external covering called an
exoskeleton.
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Insects
Insects are one type of arthropod. Insects have
three body regions a head, a thorax, and an
abdomen.
Antennae
Compound
Eyes
Six Legs
All insects also have six legs, one or two pairs
of wings, one pair of antennae, and a pair of
compound eyes.
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Parts Of The Head
Use the diagram below to identify the parts of
the head on your grasshopper.
The grasshopper has 5 eyes, two compound eyes
and three simple eyes. The antenna are sensory
organs located on the head.
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Mouth Parts
Use the diagram below to identify the mouth parts
on your grasshopper. As you identify each part,
try and remove it with your tweezers.
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The labrum is used to hold food. The mandibles
are Teeth used to chew food. The maxilla are
used to chew and taste food. The labium is used
to hold food while it isbeing chewed. Now use
the diagram below to locate the external
structures on your grasshopper.
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A grasshoppers eardrum, or tympanum, is located
below the second pair of wings on each side of
the thorax. Locate the tympanum on your
grasshopper using the picture below. The
tympanum is used for hearing.
tympanum
Like all insects, grasshoppers have six legs.
The front pair are used for walking, climbing,
and holding food. The middle legs are also used
for walking and climbing. The hind legs are used
for jumping.
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Grasshoppers breath through tiny holes in their
abdomen called spiracles. Try and find these
tiny holes along each side of the abdomen.
close up of
one spiracle
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A female grasshopper has a longer abdomen than a
male that ends with a four pointed tip called an
ovipositor. The ovipositor is used to lay eggs.
Look and the end of your grasshoppers abdomen
and determine if it is a male or a female.
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Internal Structure
Using your scissors, remove the three left legs.
Next, snip the end off the abdomen and insert the
tip of your scissors under the top surface of the
abdomen. Cut straight up the middle of the
abdomen all the way to the head. Only cut as
deep as the exoskeleton or you will cut through
the organs. Next, cut the same way up the
bottom surface of the abdomen to the mouth.
Remove half of the exoskeleton and pin it open as
shown on the next slide. Locate all the organs
shown on the next slide.
start cutting here
stop cutting here
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heart
(ovary)
brain
anus
esophagus
rectum
gizzard
The esophagus is used to swallow food. The crop,
gizzard, gastric ceca, stomach, large intestine,
and small intestine are digestive organs. The
rectum stores waste and the anus removes wastes
from the body. The malpighan tub- ules collect
waste from the blood. In the female grasshop-per
the ovaries produce eggs. The testes produce
sperm in the male grasshopper.
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Throw the grasshopper away, wipe your dissecting
tools off, wipe your tray out, and wash your
hands with soap and water. Answer the following
questions on a sheet of paper.
Questions Conclusions
1. What is the largest phylum in the animal
kingdom? 2. What does arthropod mean? 3. List
three characteristics that all arthropods
have. 4. What three body regions do all insects
have? 5. Name four other characteristics that all
insects have. 6. How may eyes does a grasshopper
have? 7. What are the antenna used for? 8. How
may different mouth parts does a grasshopper
have? more questions on next slide
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9. Describe the function of the following mouth
parts a. labrum- b. mandibles- c.
maxilla- d. labium- 10. What is the
tympanum? 11. Where is it located? 12. How many
legs does a grasshopper have? 13. Describe the
function of the legs a. front legs- b.
middle legs- c. back legs- 14. What are the
spiracles used for and where are they
located? more questions on next slide
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15. What is the function on the ovipositor? 16.
Was your grasshopper a male or a female? 17.
Describe the function of the following organs
a. esophagus- b. rectum- c. anus-
d. malpighan tubules- e. ovaries- f.
testes- 18. Name the six digestive organs in a
grasshopper 19. Why is a grasshopper classified
as an invertebrate? 20. How is a grasshoppers
skeleton different from yours? 21. List the
animals we have dissected so far from least
complex to most complex