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Nano Towels

Sustainable Alternatives To Paper Towels

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dry paper towel dry paper towel

colored water

Wet one paper towel and stuff it inside a toilet paper tube. Wet another paper towel and wrap it around the outside of a different tube. Record the time on your watch in your journal, then stand both tubes on end and set in a safe place. While these are drying,

stuff a dry paper towel inside a third tube. Add food coloring to the water in the spray bottle. Lay the tube down and spray it until color has seeped through the

Journal Notes

Stop time (towel inside dry):

Stop time (towel outside dry):

How long does it take for each wet paper towel to dry out?

How much spray does it take to get the towel inside the tube to turn red?

What finally causes the egg to break?

Our skin acts as a two-way transportation system. It lets water out (sweating), takes chemicals in (such as with skin lotion or medicine patches), and is easily bruised, scratched, and cut. Insect exoskeletons slow cardboard and stained the paper towel. Place an egg inside the fourth tube. Roll it across the ground until the egg breaks.

down water loss due to evaporation. They also keep unwanted chemicals (such as bug spray) from being taken in. Exoskeletons protect insects from cuts, scrapes, and bruises when they run into things.

There are two main disadvantages to exoskeletons. Every time an insect grows, it has to shed its skin. While it is shedding its exoskeleton, an insect's body is soft, making it easier for other animals to attack and eat it. And the exoskeleton limits how big an insect can get. You will never see a beetle the size of a small dog—the exoskeleton would be too heavy.

During the summer, the shed exoskeletons of cicadas (si-KA-das) can be found clinging to trees, fences, and even houses. While one type of cicada, known as dog day cicadas, appears each year, periodical cicadas live underground as nymphs for either 13 or 17 years.

Heads Up!

There are three main parts to an insect's head: the antennae, the eyes, and the mouth. How these three parts look and are used depends on what senses an insect needs to be successful where it lives. A cave cricket spends most of its time in caves, hollow trees, or under rocks. Being able to see well is not as important as being sensitive to smells and touches. So its eyes are very small, but its antennae are longer than its whole body. On the other hand, a fly has tiny antennae but its compound eyes take up two-thirds of its head. If a fly had a head the size of yours, its eyes would be about the size of cantaloupes. This lets a fly see almost all the way around its body without ever having to turn its head.

People use antennae on televisions, radios, and other electronic devices to get better signals. Insects use their antennae to get better signals, too. Insect antennae

Since worker honeybees do not mate and they often clamber into flowers to get nectar, honeybees have short, simple antennae. Moth antennae are often large and featherlike so they can detect small amounts of airborne chemicals to find a mate, but they don't get in the way since moths have long, tube-like mouthparts to obtain flower nectar. Can you determine other reasons for the different types of antennae?

Since worker honeybees do not mate and they often clamber into flowers to get nectar, honeybees have short, simple antennae. Moth antennae are often large and featherlike so they can detect small amounts of airborne chemicals to find a mate, but they don't get in the way since moths have long, tube-like mouthparts to obtain flower nectar. Can you determine other reasons for the different types of antennae?

can be used to taste, touch, smell, and hear. There are at least 14 types of antennae.Antennae are different lengths and shapes, and have a different number ofjointed segments. Entomologists often use the shape and the size of antennae to help them identify insects.

Insects have two kinds of eyes, simple and compound. In larvae, the simple eyes, called ocelli (o-SEL-i), can detect some colors and shapes, while the ocelli in adult insects are sensitive to light and movement but cannot see images.

It is the compound eyes on nymphs and adults that really see

things. They are called compound eyes because each eye is made of between two and 23,000 lenses. Even with all these lenses, most insects are near-sighted—they can only see things that are pretty close to them. However, they can focus on things that we would need a microscope to see!

People use fingers, forks, spoons, straws, and cups to help get food into their mouths. While insects don't eat exactly the same way we do, they have mouthparts adapted to do many of the same jobs.These mouth-parts determine the type of food an insect can eat.

A plantastic Feast

Because their mouthparts limit the types of food they can eat, most insects must be able to travel to find enough food.

A single plant can provide food for many different insects, with each kind feeding on a separate part of the plant. The coiled tube mouthpart of a butterfly is great for sipping nectar but is useless in trying to bite a green leaf. The chewing mouthparts of a grasshopper make a quick dinner of a leaf but can't pierce the stem to drink the sap.The piercing-sucking mouth of the spittlebug can do two jobs, first making a hole in the stem, then sucking out the plant juice, but can't soak up the juices that dribble down the side or spill on the ground. However, nothing goes to waste, as those juices are great for the sponging mouth of the fly.

Materials

Juice bag

Pointed-end straw (from the juice bag) 1 sheet of green construction paper Tape

Sturdy plate (not paper) Lettuce or spinach leaves

1 sheet of red construction paper Pencil

Scissors

Small paper cup Juice

2 Straws Pliers

1 inch (2.5 cm) piece of clean sponge

Remove the straw from the juice bag.Wrap the sheet of green construction paper around the juice bag, tape it in place, and set it on the plate to create the stem of your plant.Tape the lettuce or spinach leaves to the side of your stem. Draw some flower petals on the red paper, cut them out, and tape them around the top rim of the small paper cup. Tape the cup to the back edge at the top of the stem and pour a bit ofjuice inside.

Now it is time for your plant to become dinner. Start out with

a straw and take a butterfly sip of the nectar in the cup. Next, pick up the pliers and use them as a grasshopper would, ripping a leaf off the stem and taking it to your mouth. Use the pointed-end straw as your spittlebug mouth to jab a hole in the stem of your plant, then gently squeeze the stem as you sip some plant sap. To slurp up the juice that landed on the plate, put the sponge on the bottom of the straw. Move it around, then take your drink as a fly.

Thorax Up Close

Attached to the top of the thorax is the most noticeable part of many insects—the wings. Insects are the only types of invertebrates that have wings.Wings can be used to fly, to make sounds, and as protection.Wings also help entomologists identify the insects they catch.

Entomologists look to see:

• How many wings does the insect have? (Flies only have two wings. Almost all other flying insects have four, although some have none at all.)

• What do they look like? Are they like cellophane, leather, scaly, or a hard shell?

• How does the insect hold its wings when it is not flying? Are they out to the side? Above its body like a tent? Tucked away?

• What do the wing veins look like?

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