Chapter 10 Grasshopper dissection

What is a grasshopper?

A type of insect that is usually solitary and does not form large groups.

What is a locust?

A type of grasshopper that can change behavior and become gregarious, forming large swarms.

What is the main difference between grasshoppers and locusts?

Behavior — grasshoppers are solitary, while locusts can become gregarious and swarm.

In how many behavioral states can locusts exist?

Two behavioral states: solitary and gregarious.

Why are locust swarms considered dangerous?

Because they cause massive crop destruction during invasions

What is the most abundant class of arthropods?

Insects

Where can insects live?

In dry environments and many other habitats.

What are the three main body regions of an insect?

Head, thorax, and abdomen

What is the insect exoskeleton made of?

Chitin, a protective material also found in fungal cell walls.

Why do insects molt?

To grow, they must shed their exoskeleton.

How many legs do insects have?

Six legs

How many antennae do insects have?

One pair of antennae

What type of eyes do insects have?

Compound eyes

How many wings do insects have?

One or two pairs of wings

Where are insect wings attached?

To the thorax

How many eyes does a grasshopper have?

Five eyes.

What are compound eyes?

Eyes made of hundreds of images sent to the brain.

Why can’t you sneak up on a fly or grasshopper?

Because compound eyes detect shape, color, and movement.

Where are the eyes located on a grasshopper?

On top of the head.

What are simple eyes used for?

They detect light only.

Sensory organs that detect odors, touch, humidity, wind direction, and velocity.

Are antennae

Where are antennae located?

On the head.

What are insect mouth parts evolved for?

The special needs of each insect.

What are mouth parts ONLY used for?

Eating (not breathing).

What is the labrum?

The lip, used to guide food to the cutting mandibles.

What are mandibles?

Teeth used to cut and grind food.

What are maxillae?

Soft, flexible parts that act as utensils for manipulating food.

How many legs do grasshoppers have?

Six legs.

What are the front legs used for?

Walking, climbing, and holding food.

What are the middle legs used for?

Walking and climbing.

What are the hind legs used for?

Jumping.

What is the tympanum?

The eardrum of a grasshopper.

Where is the tympanum located?

Below the second pair of wings on each side of the thorax.

What is the tympanum used for?

Hearing.

How do grasshoppers breathe?

Through spiracles in the abdomen.

What are spiracles?

Tiny holes that connect to air tubes (tracheae).

What do tracheae do?

Branch to all parts of the body and make up the respiratory system.

What happens if you spray a grasshopper with soapy water?

It suffocates and dies.

How does a female grasshopper’s abdomen differ from a male’s?

It is longer.

What structure is found at the end of a female grasshopper’s abdomen?

The ovipositor.

What is the ovipositor used for?

Laying eggs.

How can you tell if a grasshopper is male or female?

By looking at the end of the abdomen.

How does fertilization occur in grasshoppers?

Fertilization is internal, like all insects.

How does the male grasshopper transfer sperm?

The male introduces his penis into the female ovipositor, releasing sperm.

How does sperm reach the eggs?

Through fine canals.

What does the female grasshopper do after fertilization?

She lays the fertilized egg pod using her ovipositor.

Where are grasshopper eggs laid?

1–2 inches underground, sometimes in plant roots or manure.

What does an egg pod look like?

It contains several dozen eggs that look like thin rice grains.

What happens when the first nymph hatches?

It tunnels up through the ground, and the rest follow.

How do grasshoppers develop?

Through stages, progressively getting larger in body and wing size.

What is the function of the esophagus?

To swallow food.

What is the crop?

A structure that stores food.

What is the gizzard?

Helps grind food.

What are gastric ceca used for?

They produce enzymes for digestion.

What organs are involved in digestion?

Crop, gizzard, stomach, small intestine, and large intestine.

What does the rectum do?

Stores waste.

What does the anus do?

Removes wastes from the body.

What are Malpighian tubules?

Structures that remove urea and salt waste from the blood.

What do ovaries produce in female grasshoppers?

Eggs.

What do testes produce in male grasshoppers?

Sperm.

What type of circulatory system do insects have?

An open circulatory system.

What is insect “blood” called?

Hemolymph.

Where does hemolymph flow?

Through the body cavity called the hemocoel.

What structures make up the closed portion of the circulatory system?

Tubular hearts and an aorta.

Where are the hearts located in a grasshopper?

Along the dorsal side of the insect.

What do the hearts do?

Pump hemolymph into the sinuses of the hemocoel

Where do exchanges of materials take place?

In the hemocoel.

What are the three main body regions of a grasshopper?

Head, thorax, and abdomen.

What are the three thorax segments called?

Prothorax, mesothorax, and metathorax.

What are the two types of wings?

Fore wings and hind wings.

What structure is used for hearing?

The tympanum.

What is the ovipositor?

A structure used by females to lay eggs.

Name leg parts shown on the diagram.

Coxa, trochanter, femur, tibia, tarsus, claw, pulvillus.