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Activity 3 - Fish Anatomy: A Comparison Between Temperate and Antarctic Fishes

data | hook | main | background & resources | student

Author Contact Information

Frederick D. Atwood
Biology Teacher, Flint Hill School, Oakton, VA
atwood@tea.rice.edu

TEA teacher Oct/Nov1998 at McMurdo Station, Ross I, Antarctica

Overview
In this activity students will dissect a fish purchased from a fish market to study its external and internal anatomy. They will observe its gills, kidney?, and blood in the microscope and will take a variety of measurements about many of the internal organs. They will practice their observation skills by making accurate illustrations. Then these data and drawings will be compared with some Antarctic fishes from the family Notothenidae in order to direct a discussion on morphological adaptations for survival in polar seas.

Students will...

  • practice scientific illustration and other observation skills
  • use a microscope to observe gills, red blood cells, and ?kidney glomeruli?
  • dissect a fish to observe its internal anatomy
  • determine the % of body weight of various fish organs
  • perform a red blood cell count using a microscope
  • determine the conductivity of fish blood as an indication of ion concentration in blood
  • pool class data and determine range and averages
  • compare average class data with that of temperate marine fish using bar graphs, data tables and class discussion

    Grade Level/Discipline
    Biology and AP Biology: Grades 9-12; Possibly Life Science Grade 7

    National Standards

    Pre-activity set-up

  • Purchase fish (with their guts intact) from a fresh fish market the day of the lab if possible.

  • Keep the fish refrigerated or on ice. Immediately after class each day put the fish back in the refrigerator.

  • Photocopy the Student Reproducible Masters

  • Put Data Table on board for each group to record their quantitative data so you can get the range and average for the class for comparison with Antarctic Fish.

    Materials
    Each team of 2-4 students should have ...

  • a microscope with 10-400x magnification
  • 1 or 2 microscope slides and cover slips
  • pipette (eye dropper)
  • lens paper
  • dissection kit and tray
  • fresh fish with internal organs intact, on ice until ready to dissect
  • a scale that can weigh up to 3000 gram and with .1 gram precision
  • rulers with mm markings

    Time Frame

  • external and gills = 1 period
  • blood and dissection = 3 periods
  • discussion = 2 period

    Engagement and Exploration (Student Inquiry Activity)
    Intro Ask students to recap the things they learned from Polar Fish Activities 1 and 2 and what they remember about what the conditions are like in Antarctica as compared to a temperate ocean.

  • Tell them about today’s activity in which they will dissect a fish market fish from temperate waters in order to make comparisons with some Antarctic fish to try to determine some of the adaptations of Antarctic fish for living in polar waters.

  • Ask the students what they think would be important things to compare between a temperate and Antarctic fish. As they come up with ideas list these on the board and ask them why they think these would be important. Jot down these reasons next to their ideas. Also ask them how they should be compared. Get them to suggest a way to quantify whatever comparisons they can (how can they be measured?). Through your questions direct the students to come up with most of the topics that will be studied in this activity. For instance, if they are not coming up with any comparisons of the eyes or other sense organs, ask them about the light conditions in Antarctica and how that might affect the fish’s food-finding ability. They might come up with a need for larger eyes or greater ability to hunt by smell or greater ability to sense vibrations in the water. Then you will ask about how these abilities could be compared in a dead fish.

    The Fish Exterior Details of procedure are on SRM Polar Fish 3.1. In short the students will do the following. It should take about 1 class period for these activities.

  • Description of fish exterior. Sketch the fish. Measure dimensions. Fin tracing. Fin weights.
  • Determining buoyancy: Weigh the fish in air and in water.
  • Trace the lateral line on your sketch. Measure the dimensions of the lateral line.
  • Scrape off the scales and weigh them. Determine what % of body weight the scales are.
  • Eye weight and eye dissection. Compare with mammal eye.
  • Describe the teeth and try to hypothesize about the diet
  • ? Look at and weigh the nasal lamellae?

    Gills and Blood Details of procedure are on SRM Polar Fish 3.1. In short the students will do the following. It should take about 1 class period for these activities.

  • Observe operculum, gills, gill rakers
  • Weigh gills
  • Count gill arches, filaments per gill arch.
  • Measure length and width of a gill filament
  • Observe a gill filament in microscope
  • Propose a method for estimating the surface area of the gills. Then try it.
  • Do you think the Antarctic fish will have more or less surface area than the temperate? Why?
  • Remove some blood from the fish and observe blood cells, do a red blood cell count and
  • measure the conductivity of the blood as a way of measuring its salt content.
  • How do you think Antarctic fish blood will be different and why?

    Internal Anatomy Details of procedure are on SRM Polar Fish 3.1. In short the students will do the following. It should take about 2 class periods for these activities

  • Dissect the fish and observe the following. Observe these in situ, without removing them from the body so you can see the relationship between the organs: air sac, heart, spleen, stomach, intestine, kidney, liver, any other identifiable
  • organs
  • See Student Reproducible Master Polar Fish 3.2 for diagram to ID body parts
  • Diagram the innards. Be sure to note any differences from the Polar Fish 3.2
  • ?Map fat distribution in the body.?
  • Remove and weigh the following organs: heart, spleen, digestive tube, kidney, liver, fat, other identifiable organs
  • ?Cut a paper thin slice of kidney and observe under the microscope to look for glomeruli.?
  • ?Boil all the meat off the bones, remove the bone and cartilage from the mush. Then remove the bone from the cartilage and weigh the two separately to determine the ratio of bone to cartilage, and % body weight of each.?
  • ?While boiling the meet off the bones, also put the other organs in the pot. After the boiling is done, decant off the fats and oils which should be floating at the top. Weigh this fat and determine % of body weight that is fat.

    Explanation (Discussing)

  • 1. Give the students SRM Polar Fish 3.2 Drawings and Photos of Antarctic Fishes

  • As the students look at these diagrams and photos list on the board the differences they see between these different types of fish. Be as specific as possible. For instance instead of simply saying "fin shape", say "pectoral fins of fish X are bigger than the others and these fins have longer rays that project beyond the edge of the fin". Then have the students try to explain how these differences might be adaptive for a specific ecological niche. Have the students try to determine what the ecological niche is of the fish. Next to each difference list the students’ ideas about how the differences are adapted for the different niches of the fishes. In the background section of this activity you can see a description of the niches of these polar fishes and the most noticeable adaptations that they have for their niche.

  • Then have the students discuss the probable niche of the fish they dissected. Compare the Antarctic fish which occupies that niche with the dissected fish. Are there any differences that they think are related to polar vs temperate regions? If so hypothesize about reasons for these differences.

  • 2. Give the students SRM Polar Fish 3.3 (charts giving statistics on various Notothenioid fishes measurements similar to the ones the students recorded in their investigations). For homework have them look it over and compare the data with their own data on the temperate fish that they dissected. They should list 5 new differences they notice and try to hypothesize reasons for these differences. In the background section of this activity there is a list of some of the significant internal differences between Notothenioid fish from Antarctica and temperate fish and an explanation of why these differences are adaptive.

  • In class next day lead a discussion on these assignments. I generally do this by collecting the assignments and reading some of them out loud for the class to comment on and add to.

  • 3. Another very interesting activity about the gills of Notothenioid fish explores the effect of X-cell disease which decreases surface area of the gills is available at the following website. Click on the web address to see this site. http://www.icair.iac.org.nz/education/resource/selfstud/fishst/fish.htm

  • Concepts and terms you may need to describe or review for these discussions are listed below. These same topics are described in the background section of this activity.
  • the functions of gills in fishes (gas exchange and regulation of salt, ion, and pH balance)
  • the function of red blood cells and hemoglobin (carry oxygen)
  • the effect of temperature on blood viscosity
  • the effect of temperature on dissolved oxygen concentration
  • the functions of heart, spleen, liver, kidney, skin, pancreas
  • ecological niche
  • adaptations of Antarctic fish for living in polar oceans

    Elaboration (Polar Applications)

    Exchange (Students Draw Conclusions)

    Evaluation (Assessing Student Performance)
    I grade the ... 1. lab data (sketches , observations, data) looking at accuracy, thoroughness, and clarity of explanation.

    2. homework assignment looking at accuracy, thoroughness, and clarity of explanation.

    I also include questions on my tests/quizzes that cover the major concepts and some of the most striking differences that were observed in the lab.

    data | hook | main | background & resources | student