Conditions necessary for germination of seeds

Transcription

1 Teacher's/Lecturer's Sheet Conditions necessary for germination of seeds (Item No.: P ) Curricular Relevance Area of Expertise: Biology Education Level: Age Topic: Plants Subtopic: Germination and growth Experiment: Conditions necessary for germination of seeds Difficulty Preparation Time Execution Time Recommended Group Size Intermediate 10 Minutes 40 Minutes 2 Students Additional Requirements: Experiment Variations: Garden soil Bean or pea seeds Keywords: Germination Task and equipment Information for teachers Additional Information Germination refers to the development of the seed of seed plants, this includes the whole process of development, starting with the swelling of the seeds and the growth of the embryo in the fertile seeds, via the formation of the radicle until the complete formation of the seedling. In this and the following experiments (2.3 Swelling, 2.4 Germination and water, 2.6 Germination and oxygen, 2.7 Inhibition of germination in fruits) the students are supposes to explore which conditions influence the germination of seeds. Hints on Setup and Action The garden soil needs to be completely dry for this experiment. Spread it out on a sheet of paper and let it dry till it can be crumbled into dust before starting this experiment. In order to achieve reasonable results, the experiment should be carried out over at least 6 days.

2 Conditions necessars for germination of seeds (Item No.: P ) Task and equipment Task Which conditions need seeds for germination? Examine, on which conditions the germination of seeds depends.

3 Equipment Position No. Material mrder No. Quantits 1 Petri dish, d 100 mm Circular filter,d 90 mm,100 pcs Beaker, 250 ml, low form, stackable, plastic Spoon,w.spatula end,18 cm,plastic Labor pencil, waterproof Additional material Set-up and procedure Garden soil Bean or pea seeds Fill two 100 mm diameter Petri dishes with dry garden soil to a depth of 1 cm. It is essential that the garden soil is completely dry. Fig. 1 In each of two other 100 mm diameter Petri dishes place three circular filters of 90 mm diameter and smooth them out on the bottom of the dishes.

4 Fig. 2 In each of the four Petri dishes place 5-8 dry bean or pea seeds. In the dishes containing garden soil the seeds should just peep out of the soil. Fig. 3 Into one of the dishes with the circular filters pour just enough water to cover the seeds. Into one of the two dishes containing soil carefully pour just enough water for the soil to be well and evenly moistened. Fig. 4 Label the dishes, so you know which dishes need to be kept moist. Place the lids slantingly on the dishes so that the water does not evaporate too quickly from the dishes which have been kept moist and so that air can enter all the dishes.

5 Fig. 5 Controll the seeds daily over a period of at least 6 days. What changes can you notice? Write down your observations on the Results page. Water the seeds lying on wet circular filters or moist garden soil, regularly. The circular filters and the garden soil should be kept moist, but not too wet.

6 Report: Conditions necessary for germination of seeds Result Observations (10 Punkte) Describe the daily changing of the seeds. Does the size of the seeds changes? After how many days begin the seeds to germinate? Bhich parts of the plant can you see? Evaluation Question 1 (10 Punkte) In which dishes do the seeds germinate?

7 Evaluation Question 2 (10 Punkte) Bhat happens at the beginning of the germination of the seeds? Evaluation Question 3 (10 Punkte) Bhat is needed for this, and hence for germination, to occur?