Sketch a Fish
This activity could be used for pre and post unit assessment. At the beginning of the unit have students draw a fish and label all the parts they can. After your visit to the National Aquarium have the students repeat the activity. The My Fish Drawings worksheet
could be used for this activity.
The Challenges of Marine Environments
As a class list the differences between living in water and living in air. Think about what special environmental challenges aquatic animals face that terrestrial animals do not.
Discuss how the physical features of fish enable them to live in the aquatic environment successfully. What are these physical features? Students could name these features and explain what function they think they perform. Depending on the level of your students, encourage them to use some of the vocabulary below in their discussion.
External Characteristics - Fins (caudal, anal, dorsal, pectoral, pelvic), scales, lateral line, gills, mouth, eyes…
Internal Organs - Heart, swim bladder, liver, intestines, stomach, kidney, brain…
A Close-up Look - External
Obtain a dead fish from a fish shop, fisherman, or supermarket. A large fish is better for this activity as the physical characteristics are easier to identify. Let the students touch the fish and feel the scales and fins. Point out the different fins, the lateral line, the mouth and eyes, the gill cover and gill slit, and the nostril.
Refer to the Anatomy of a Bony Fish - Answers
sheet to assist you if necessary. Insert a small pipe or funnel into the mouth of the fish and run water through it to observe the flow of water from mouth to gills.
The Catfish jigsaw puzzle
is another useful way of reinforcing the correct terms when describing the external anatomy of a fish. Students can reconstruct the Catfish and name the pieces of the puzzle. An original Catfish illustration can be viewed on the Catfish sheet
A Close-up Look - Internal
Dissect a fish and examine the internal organs. Question the students on the function of these organs, particularly those unique to fish such as the swim bladder and the gills.
Have students complete an observational drawing of the internal organs of the fish. As an extension have students label the major organs.
Compare Two Different Fish
This activity introduces students to the concept that while all fish have shared external physical features, these features can differ in size, shape and function.
Students can observe photographs or sketches of two different fish and construct a Venn diagram to compare them. Sketches of a Trevally and Bannerfish can be printed from the Fish Comparison sheet
Each fish will have its own circle headed with the name of the fish and characteristics that are unique only to that fish and not shared by the other. The intersecting part of the circles will contain characteristics both the fish share. An example is outlined in the table below.
Function of Parts of a Fish
The Function of Parts of a Fish worksheet
can be used to explore the function of the different parts of a fish. Students will cut out the boxes and pair up the part of a fish with the description of its function. These may be glued into the student's exercise books.
Physical Fish Features
Show students a range of pictures showing different fish. Discuss how they differ physically, including in the discussion the range of tail shapes, body shapes, position of the mouth, body size, eyes and colour. In small groups have students share their views on how these differences may affect the way a fish lives.
Have the students design their own fish. Students could pretend they are marine biologists who have discovered a new species of fish. Students need to think about what they have learned about the physical features of different fish and consider these features in their fish design.
Students could make a 3D model with their own craft materials or the fish could be constructed using large cartridge paper folded in half, cut, coloured, stuffed and stapled together.
Have students write a creative and informative description of their fish, which could be attached to their completed fish.
Information the students should consider when designing and describing their fish includes:
Name of their fish
Type of fish; jawless fish, cartilaginous fish or bony fish
Habitat, where does your fish live in the ocean: coral reef, open ocean, deep ocean, and rocky shore…
Migration, does your fish migrate or does it live in the same place its entire life?
Location in the world
Colouration/camouflage, defence adaptations
How they swim/move/anchor
Physical features; body shape, type and number of fins, scales, size, mouth position, eye position and size…
Predators and prey; what does the fish eat and what eats the fish?
The Swimming and Feeding Pattern activity cards
could be a useful assessment of what students have learned about the different external anatomy features of fish. Photocopy and cut up each section of this table separately. Have students work in pairs to reform the original table, closely observing the tails, mouths, swimming and feeding patterns, and information cards.
Ask the students to give reasons for their decisions and as a class compare their matches and discuss their justifications.
Have students explore the concept and function of the fish swim bladder. Fish vary their depth in water using their swim bladder, when they want to come nearer to the surface of the water they inflate their swim bladders with air and to go deeper in the water they deflate their swim bladders. It is important to emphasise to the students that fish vary the amount of air in their swim bladder, not the amount of water as this model may lead them to believe.
Activity: Use a soft drink bottle to represent the swim bladder and put varying amounts of air and water in it.
A bottle with only air in it will float on the very top of the water surface.
A bottle with 50% air and 50% water will sit somewhere between the water surface and the bottom.
A bottle with no air in it will sit on the bottom.
Set a challenge for the students to create a soft drink bottle fish that sits 30cm below the surface of the water.