Copyright © The Norwood Science Center 2006
Norwood Science Center
Animals
Grade 3
Background Information:
Fish belong to the group of animals that are called coldblooded. They do not have cold blood; rather their environment
governs their blood temperature. Cold water, cold fish, warm water,
warm fish. This characteristic is shared with all animals on the planet
Earth with the exception of the birds and mammals.
Fish also belong to a group that is characterized by the
presence of a backbone. While there is some variety amongst the
fish groups, for our study they will all be considered bony animals
with a backbone.
While fish share many traits with animals from other groups
they have a few specialized features. The first would be the
presence and use of gills. Gills are the breathing organs of most
aquatic animals, including mollusks and crustaceans. Fish have gill
slits or a flap of skin covering the gills. Under these gill slits are the
gills themselves that are analogous to the capillaries surrounding the
alveolus in the mammalian lung. The gills are very thin blood
vessels. Water is pulled into the mouth of the fish with the gill slits
closed. As the mouth is closed the water is pumped past the gills and
out the gill slits. As the water passes amongst the gills oxygen
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passes into the blood and carbon dioxide passes from the blood to
the water.
Aside from the obvious physical characteristics such as scales
and fins the fish posses a remarkable adaptation. Two water filled
tubes can be found just under the skin of the fish that run almost the
length of the body. These are the lateral lines and help the fish
detect water currents, and pressure changes, which are pretty good
skills if you are in the water when it is dark. These lateral lines are a
feature shared with amphibians that spend most of their life in the
water.
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Copyright © The Norwood Science Center 2006
TITLE:
FISH
PURPOSE:
What are characteristics of fish?
MATERIALS:
(per group of 3-4)
3-4 Label the Fish worksheets
Pencils
1 Plastic Fish Tub
1 Goldfish (not all goldfish are yellow)
Aquarium Water as needed
Notebooks
PROCEDURE:
01. Group the students.
02.
Tell the students they will be seeing a fish in a few moments.
But first they are to draw what they think a fish looks like in their
notebooks. Students can brainstorm momentarily, and then
they must draw a fish.
03.
Distribute the plastic fish tanks.
04.
Fill the tanks three quarters full with aquarium water. Aquarium
water is simply water that has been left out for two days and
checked for pH. Leaving the water out allows for the
temperature to level off at room temperature and any harmful
gases to evaporate. The water used in the Science Center
lesson is water from an actual aquarium; it will be the least
stressful for the fish.
05.
Place one fish in each fish tank.
06.
Allow the children to observe the fish for several minutes in
complete silence. They are to make notes regarding the
anatomy (the body parts), physiology (the function of these
parts) and any interesting behaviors the fish may demonstrate.
07.
Have the students observe the activity of fish to see if they can
detect how many fins and what each of them may be used for.
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08.
After a few minutes of silent study, the students are to discuss
any changes or differences they found between what they
expected and what they observed.
09.
Distribute a Label the Fish worksheet to each student. Guide
them as they match up the vocabulary words with the diagram.
10.
Explain to the students that the gills are the "lungs" of the fish.
Students should understand the gills are the sites of gas
exchange in the respiratory system of the fish.
11.
Explain to the students that the fish takes "breaths" like higher
animals on land. The breaths can be counted by watching how
many times the gill slits or covering (operculum) open and shut.
12.
(Optional) Have the students count the number of times the fish
"breathes" in 15 seconds. Can the students calculate the
breathing rate in breaths per minute?
13.
Explain the function and location of the lateral lines. Students
are to include this detail on their Label the Fish worksheet.
SOURCE:
01.
Critters. AIMS Education Foundation, 1992.
02.
The Usborne Illustrated Dictionary of Science.
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Name ___________________________________________
Label the Fish
Read the vocabulary words and their definitions
Then label the fish diagram below using the vocabulary
words


Anal fin* – the fin on the lower side of the body near the tail
Caudal fin* – the tail fin
Dorsal fin* – the fin on the upper side of the body
Eye – sight organ located on the head
Gill slits – covers the gills. Opens and closes. Located on the side
of the head.
Lateral line – a series of small openings that are located along
the sides of the fish. Used to sense vibrations in the water.
Mouth – the part of the body that the fish uses to catch food.
Located at the front of the body
Pectoral fin* – each of the paired fins on either side of the body.
Located near the head.
Ventral fin* – each of the paired fins on the lower side of the
body towards the head.
6
1
7
2
3
4
8
5
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