Dissection of a Dissection of a GrasshopperGrasshopper

Kathy Biernat

May 2007

What is a grasshopper?What is a grasshopper?

A grasshopper is an arthropod. It hasA grasshopper is an arthropod. It has Jointed appendagesJointed appendages A segmented bodyA segmented body An exoskeletonAn exoskeleton

Grasshopper Facts:Grasshopper Facts:

Country:Country: Worldwide WorldwideHabitat:Habitat: meadows, fields, and hedges meadows, fields, and hedgesLength:Length: up to 3 in. (8cm) but mostly 5/8 - up to 3 in. (8cm) but mostly 5/8 -1 1/8 in. (15-30 mm) 1 1/8 in. (15-30 mm) Weight:Weight: almost nothing almost nothingClosest relative:Closest relative: katydid and cricket katydid and cricket

Why dissect a Why dissect a grasshopper?grasshopper?

To identify the external and To identify the external and internal anatomy of the internal anatomy of the grasshoppergrasshopper

To practice basic dissection To practice basic dissection skillsskills

Explore this site to learn Explore this site to learn more about more about grasshoppers.grasshoppers.

http://www.ris.net/~lawnman/hopfaq.html#GUTS

Get ready to learn more Get ready to learn more as we dissect a as we dissect a grasshopper!grasshopper!

Step OneStep One

Identify the materials you will need for Identify the materials you will need for your dissection.your dissection.

Dissection Tray

Hand lens

Materials, continuedMaterials, continued

RulerRuler ScalpelScalpel ScissorsScissors Eye dropperEye dropper Dissection pinsDissection pins Forceps (tweezers)Forceps (tweezers)

Materials, continuedMaterials, continued

GlovesGloves GogglesGoggles And a grasshopper!And a grasshopper!

Study the external parts Study the external parts of the grasshopperof the grasshopper

Step Two: Identify theStep Two: Identify the

HeadHead ThoraxThorax AbdomenAbdomen Notice also the eyes, Notice also the eyes,

antennae, legs and antennae, legs and wingswings

SkeletonSkeleton

The grasshopper has The grasshopper has a hard exoskeleton. a hard exoskeleton. That means its That means its skeleton is located skeleton is located on the outside of its on the outside of its body, not internally body, not internally like ours. This like ours. This skeleton is made of skeleton is made of chitin, a chitin, a carbohydrate.carbohydrate.

The headThe head

A Frontal View of the A Frontal View of the headhead

The compound eyeThe compound eyeThe grasshopper has two The grasshopper has two

compound eyes that compound eyes that are made up of are made up of hundreds of individual hundreds of individual eyelets. eyelets.

Observe the antennaeObserve the antennae

The grasshopper's The grasshopper's head has two head has two antennae that are antennae that are able to feel and smell able to feel and smell what is nearby. what is nearby.

The mouthThe mouth

The mouthparts are The mouthparts are a set of movable a set of movable jaws that let the jaws that let the grasshopper chomp grasshopper chomp its way through grass its way through grass blades. blades.

The mouthThe mouth

Labrum - the broad upper lip Labrum - the broad upper lip Hypopharynx - the tongue Hypopharynx - the tongue Mandibles - two heavy Mandibles - two heavy

blackish jaws with teeth along blackish jaws with teeth along the inner margin. The the inner margin. The mandibles move up and mandibles move up and down. down.

Maxillae - two smaller jaws Maxillae - two smaller jaws that move side to side that move side to side

Labium - the lower lip Labium - the lower lip Palp - maxillary and labial Palp - maxillary and labial

palps are sensory palps are sensory appendages appendages

The thoraxThe thorax

The legsThe legs

Using huge hind legs, Using huge hind legs, the grasshopper makes the grasshopper makes gigantic leaps into the gigantic leaps into the air.air.

Long legs are an Long legs are an advantage for jumping, advantage for jumping, because they increase because they increase the distance over which the distance over which the jumper can push off the jumper can push off the ground the ground

The legs, continuedThe legs, continued

When a grasshopper When a grasshopper jumps, it first jumps, it first crouches down, crouches down, there is then a short there is then a short delay, and then off it delay, and then off it goes.goes.

Back leg- knee

The leg, continuedThe leg, continued

The two rear legs are The two rear legs are specialized and specialized and strengthened for strengthened for jumping, while the jumping, while the front two pairs are front two pairs are used only for walking used only for walking on the ground on the ground

The Wings The Wings

The two pairs of The two pairs of grasshopper wings grasshopper wings differ in shape, differ in shape, structure, and structure, and function. The hind function. The hind pair are responsible pair are responsible for flight.for flight.

Close up of the wingsClose up of the wings

After its spring-After its spring-assisted takeoff, it assisted takeoff, it can unfurl its two can unfurl its two pairs of wings and pairs of wings and continue flying with continue flying with them.them.

The abdomenThe abdomen

The hind region of The hind region of the grasshopper’s the grasshopper’s body, the abdomen, body, the abdomen, consists of 11 consists of 11 segments.segments.

The AbdomenThe 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 Determine the sex of your grasshopperyour grasshopper

Close upClose up

Female

Male

Reproductive organsReproductive organs

Female

Reproductive organsReproductive organs

Male

TaskTask

Draw a diagram of the external parts of the Draw a diagram of the external parts of the grasshopper. Label at least the grasshopper. Label at least the

following:following: HeadHead ThoraxThorax AbdomenAbdomen Compound eyeCompound eye AntennaeAntennae Wings (forewing and hindwing)Wings (forewing and hindwing) Mouth Mouth

Step Three: MeasureStep Three: Measure

MeasureMeasure

Be sure to record the length of your Be sure to record the length of your grasshopper.grasshopper.

Measure the grasshopper from the tip of Measure the grasshopper from the tip of the head to the end of the abdomen.the head to the end of the abdomen.

We will collect these measurements at We will collect these measurements at the end of the dissection lab and the end of the dissection lab and compare!compare!

Step Four: The Dissection Step Four: The Dissection begins: begins: Position the grasshopper dorsal side upPosition the grasshopper dorsal side up Carefully remove the protective sheath from the Carefully remove the protective sheath from the

scalpel.scalpel. Hold the grasshopper firmly.Hold the grasshopper firmly.

Cut along the dorsal surface Cut along the dorsal surface of the thorax and abdomenof the thorax and abdomen

Gently pull the Gently pull the exoskeleton asideexoskeleton aside

You may wish to use the You may wish to use the dissection pins to make dissection pins to make viewing easier.viewing easier.

Using a hand lens, identify as many of Using a hand lens, identify as many of the internal organs as possiblethe internal organs as possible

Digestive Digestive SystemSystem

These are the parts of These are the parts of the digestive system :the digestive system : Mouth Mouth Esophagus Esophagus Crop Crop StomachStomach IntestineIntestine

Chewed food is stored in Chewed food is stored in the crop, digested in the the crop, digested in the stomach, and absorbed stomach, and absorbed in the intestine.in the intestine.

Observe the digestive Observe the digestive systemsystem

A little closerA little closer

The crop, gizzard and The crop, gizzard and digestive caecaedigestive caecae

The digestive caecae The digestive caecae produce enzymes produce enzymes which aid in digestionwhich aid in digestion

Respiratory SystemRespiratory System

You will probably NOT be able to see the You will probably NOT be able to see the small holes. on the side of their bodies small holes. on the side of their bodies without your hand lens. These holes are without your hand lens. These holes are called called spiraclesspiracles, each hole leads to a , each hole leads to a large tube called a large tube called a tracheatrachea. The large . The large tubes divide into small tubes that branch tubes divide into small tubes that branch out to all the cells of the body. This out to all the cells of the body. This system of tubes carries oxygen to the system of tubes carries oxygen to the cells and takes away the carbon dioxide.cells and takes away the carbon dioxide.

Respiratory SystemRespiratory System

Do you see anything Do you see anything in your grasshopper in your grasshopper that resembles a that resembles a lung?lung?

Respiratory SystemRespiratory System

The grasshopper does not have a lung. How The grasshopper does not have a lung. How then does it breathe?then does it breathe?

Air enters the spiracles and as the abdomen Air enters the spiracles and as the abdomen expands and contracts, fresh air moves in and expands and contracts, fresh air moves in and used air moves out.used air moves out.

The air enters the cells directly and is not The air enters the cells directly and is not transferred to the blood- that’s why their blood transferred to the blood- that’s why their blood is yellow, not red- it contains no hemoglobin!is yellow, not red- it contains no hemoglobin!

Circulatory SystemCirculatory System

The grasshopper’s The grasshopper’s circulatory system is circulatory system is open- that means that it open- that means that it does have a “heart”, but does have a “heart”, but the heart is more of a the heart is more of a muscular tube that muscular tube that collects the blood and collects the blood and forces it to the front of forces it to the front of the body. The blood the body. The blood freely flows throughout freely flows throughout the grasshopperthe grasshopper

The Nervous SystemThe Nervous System

The grasshopper's The grasshopper's brain is located brain is located between its eyes, between its eyes, above the above the esophagus.esophagus.

Cool fact…Cool fact…

The grasshopper does not use its brain The grasshopper does not use its brain to walk or jump! It does that without a to walk or jump! It does that without a brain.brain.

The brain is used to control the mouth The brain is used to control the mouth and to send sensory information to the and to send sensory information to the rest of the body.rest of the body.

Excretory SystemExcretory System

There are a number of tubules between There are a number of tubules between the large intestine and the stomach. The the large intestine and the stomach. The outer end enters into the body cavity and outer end enters into the body cavity and takes in the wastes. The wastes are takes in the wastes. The wastes are carried into the large intestine and out carried into the large intestine and out through the anus.through the anus.

TaskTask

Draw a diagram of the internal organs Draw a diagram of the internal organs you identified. Include at least the you identified. Include at least the following:following:

IntestinesIntestines CropCrop Reproductive organsReproductive organs

Be sure to:Be sure to:Properly dispose of your grasshopperProperly dispose of your grasshopper Remove the dissection pins.Remove the dissection pins. Pick up the grasshopper and any organs that you Pick up the grasshopper and any organs that you

may have removed. Discard them into the plastic may have removed. Discard them into the plastic bag provided.bag provided.

Be sure to dump the remaining liquid in the jar as Be sure to dump the remaining liquid in the jar as this is the last dissection. this is the last dissection.

Sanitize scalpels and pins, rulers and hand lenses Sanitize scalpels and pins, rulers and hand lenses and trays. Return them to the kit.and trays. Return them to the kit.

Wipe down lab tables and discard gloves.Wipe down lab tables and discard gloves.

MANY THANKS to….MANY THANKS to….

Miss Kelly Knipple, Science Teacher, St. Miss Kelly Knipple, Science Teacher, St. Charles Borromeo SchoolCharles Borromeo School

2006 graduating class at St. Charles 2006 graduating class at St. Charles BorromeoBorromeo

And the following web pages:And the following web pages:

http://www.uleth.ca/bio/bio1020/anim2sli.htmlhttp://www.uleth.ca/bio/bio1020/anim2sli.html http://www.amnh.org/learn/biodiversity_counts/http://www.amnh.org/learn/biodiversity_counts/

ident_help/Parts_Arthropods/grasshopper.htmident_help/Parts_Arthropods/grasshopper.htm users.rcn.com/.../ BiologyPages/I/Insects.htmlusers.rcn.com/.../ BiologyPages/I/Insects.html www.st-andrews.ac.uk/ ~wjh/jumping/legwrk.htmwww.st-andrews.ac.uk/ ~wjh/jumping/legwrk.htm www.thetech.org/.../ about/grasshopper.htmlwww.thetech.org/.../ about/grasshopper.html io.uwinnipeg.ca/ ~simmons/hopper4.htmio.uwinnipeg.ca/ ~simmons/hopper4.htm http://www.howe.k12.ok.us/~jimaskew/botzo/http://www.howe.k12.ok.us/~jimaskew/botzo/

hopper.htmhopper.htm http://wwwbio200.nsm.buffalo.edu/labs/tutor/http://wwwbio200.nsm.buffalo.edu/labs/tutor/

Grasshopper/Grasshopper/ http://io.uwinnipeg.ca/~simmons/16labman05/http://io.uwinnipeg.ca/~simmons/16labman05/

lb6pg17.htmlb6pg17.htm http://faculty.washington.edu/chudler/invert.htmlhttp://faculty.washington.edu/chudler/invert.html www.sdvc.uwyo.edu/ grasshopper/ghparts.htmwww.sdvc.uwyo.edu/ grasshopper/ghparts.htm