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1.3

Major VersionM

by Manikandan S

Introduction

These are a set of variations for the TACtivity Seed Dispersal Models.

    • Handle scissors/paper cutter with care.

    • Do not use flame near readily inflammable liquids or gas containers. Use candle under adult supervision.

  1. Some seeds disperse by explosion due to the internal tension within the seed.
    • Some seeds disperse by explosion due to the internal tension within the seed.

    • Example : Lupine (Lupinus albus), a flowering plants in the legume family with a ballistic model of seed dispersal.

  2. Cut the bottom portion of the plastic bottle about one-fourth from the base, using scissors and/or paper cutter as shown in the picture. Cut the plastic bottle about one-third from the cap, using a paper cutter and/or scissors. Using Scissors, trim the splinters along the cut edge and make it smooth.
    • Cut the bottom portion of the plastic bottle about one-fourth from the base, using scissors and/or paper cutter as shown in the picture.

    • Cut the plastic bottle about one-third from the cap, using a paper cutter and/or scissors.

    • Using Scissors, trim the splinters along the cut edge and make it smooth.

  3. Stick one end of insulation tape as shown in the picture. Rotate the cut bottle such that the entire circumference of the cut bottle's edge is taped. This will prevent the balloon from tearing off.
    • Stick one end of insulation tape as shown in the picture.

    • Rotate the cut bottle such that the entire circumference of the cut bottle's edge is taped.

    • This will prevent the balloon from tearing off.

  4. Cut a big balloon at the neck portion. The wider portion of the cut balloon is stretched to cover the wider, taped end of the model. You may need a helping hand to stretch the balloon over the cut bottle.
    • Cut a big balloon at the neck portion.

    • The wider portion of the cut balloon is stretched to cover the wider, taped end of the model.

    • You may need a helping hand to stretch the balloon over the cut bottle.

    • Secure the balloon using tape.

    • Add a few thermocol balls inside the prepared model.

    • Pull the stretched part of the balloon downward and release it, propelling the thermocol balls up.

  5. This model is an example for seed dispersal by shaking in some plants.
    • This model is an example for seed dispersal by shaking in some plants.

    • Some plants have tiny holes in their seed capsule. When the wind blows, the holes in the capsules let the seeds to fall on the ground.

    • Example: Poppy seed (Papaver somniferum).

  6. Heat one end of the thick binding wire on a candle flame for about 20 seconds. The heated end of the wire is used to make a hole in the centre of the plastic container. Enlarge the hole using scissors, to fit a stiff straw  as shown in the next step.
    • Heat one end of the thick binding wire on a candle flame for about 20 seconds.

    • The heated end of the wire is used to make a hole in the centre of the plastic container.

    • Enlarge the hole using scissors, to fit a stiff straw as shown in the next step.

  7. Insert a stiff straw through the hole made in the container. Insert the stiff straw up to the top portion of the container as shown in the picture. Now insert the free end of the stiff straw through the centre of a foam piece.
    • Insert a stiff straw through the hole made in the container.

    • Insert the stiff straw up to the top portion of the container as shown in the picture.

    • Now insert the free end of the stiff straw through the centre of a foam piece.

    • If the hole is too large, then, glue the stiff straw after inserting.

  8. Take some mustard seeds on a piece of paper. Fill the plastic container with the mustard seeds. Be careful while filling the container.
    • Take some mustard seeds on a piece of paper.

    • Fill the plastic container with the mustard seeds.

    • Be careful while filling the container.

    • Shake the stiff straw by tapping near the middle and see what happens to the seeds?

  9. In some plants, due to gravity fruits undergo abscission and fall to the ground, where their seeds are released.
    • In some plants, due to gravity fruits undergo abscission and fall to the ground, where their seeds are released.

    • Example: Calabash (Lagenaria siceraria).

  10. Cut a small ball at its centre line using scissors and/or paper cutter. Cut about three-quarters of the circumference of the ball.
    • Cut a small ball at its centre line using scissors and/or paper cutter.

    • Cut about three-quarters of the circumference of the ball.

  11. Fill a few thermocol balls inside the small ball. You can use small nuts or magnets as well instead of thermocol balls. Seal the middle cut portion of the small ball using a single drop of glue.
    • Fill a few thermocol balls inside the small ball.

    • You can use small nuts or magnets as well instead of thermocol balls.

    • Seal the middle cut portion of the small ball using a single drop of glue.

  12. Drop the model from a certain height and observe the result.
    • Drop the model from a certain height and observe the result.

    • Drop the ball from a certain height with force to attain the desired result.

    • Not able to pull the stretched balloon - Check the diameter of the cut bottle that holds the stretched balloon.

    • Not able to fix the plastic container at its position - Check the diameter of the hole to that of the stiff straw.

    • The seeds not dispersed from the ball - Ensure to drop the ball with enough force for the ball to release the seeds.

Finish Line

Madhushree HS

Member since: 05/02/2017

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