Reproduction In Flowering Plants (Brad Issler)

Title: Reproduction In Flowering Plants.

Principle(s) Investigated: 
Anatomy and physiology of plants.  The process and structures by which plants reproduce and the connection between plants and animals. 

Standards : Grade Seven, Life Science, Structure and Function in Living Systems:

5a. Students know plants and animals have levels of organization for structure and function, including cells, tissures, organs, organ systems, and the whole organism.

5f.  Students know the structures and processes by which flowering plants generate pollen, ovules, seeds and fruit.

  •  flowering plants (picking flowering plants locally provides a discrepant event to discuss.)
  •  tweezers
  •  hand lenses
  •  worksheets (attached).    

Procedure:  Students will work in pairs.  Each pair receives a flowering plant, tweezers, hand lens and worksheets.  Students will follow the procedure outlined in the worksheet titled "Flower Dissection."  

Student prior knowledge:  Students need to know the life cycle and basic structure of flowering plants.  Students need to know what a flower is, specifically.

Questions & Answers: 

Q:  Why are there more stamens than pistils? 

A:  This is an opinion based answer but hopefully students will realize that this might be because there are many vectors through which pollen is transferred, and many of the pollen grains do not make it to the pistil of another plant.  Therefore, it is important for plants to produce as much pollen as possible for the survival of this genetic material.

Q:  What are some advantages of having brightly colored petals?  

A:  Again, this is an opinion based answer, but hopefully students will remember that brightly colored petals attract certain animals that are used as a vector for transporting pollen when, after coming to the plant to collect nectar they unknowingly collect pollen on their body which can then be transferred to other flowers.

Q:  Describe the stages of the life cycle of a flowering plant.

A:  Germination-seed sprouts.  Growth-grows to a mature plant.  Reproduction-eggs produced in ovary, sperm produced/packaged in anther (2 sperm cells per pollen grain).  Pollen transferred from anther to stigma leading to fertilization.  Seed production.  Seed dispersal.  And, eventually, death.   

Applications to Everyday Life:  This applies to not only plant life cycles but, the "circle of life."  Students will realize that flowering plants are essential to all life, as we know it.  Students will realize that the fruit they eat, in flowering plants, is the structure that contains its seeds.  Also, students will know why bees (and other organisms) are necessary for the pollination of flowering plants, which might one day shape their decisions in using pesticide free food.


Videos:  And interactives

For homework or computer lab: