Topic: Adaptation of pine to environmental conditions, reproduction of pine

Target group

5th‑grade students of elementary school

New core curriculum

4) Gymnosperms - Student:

a) presenting the features of gymnospermary extraction for pine samples,

General aim of education

Students present the adaptation of pine to the terrestrial environment of life.

Key competences

• communication in foreign languages;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• You will learn about adapting pine to environmental conditions;

• you will describe the propagation of pine.

Methods/techniques

• activating

  • discussion.

• expository

  • talk.

• exposing

  • film.

• programmed

  • with computer;

  • with e‑textbook.

• practical

  • exercices concerned.

Forms of work

• individual activity;

• activity in pairs;

• activity in groups;

• collective activity.

Teaching aids

• e‑textbook;

• notebook and crayons/felt‑tip pens;

• interactive whiteboard, tablets/computers;

• glue;

• pine tree printout;

• two sheets of paper towel;

• a board showing the cross‑section of a pine needle.

Lesson plan overview

Before classes

• The teacher checks if the children have brought photos of pine growing in different environments..

• Students get acquainted with the content of the abstract. They prepare to work on the lesson in such a way to be able to summarize the material read in their own words and solve the tasks themselves.

• The teacher informs the class that the lesson is a continuation of the theme „Conifers”.

Introduction

• The teacher gives the topic, the goals of the lesson in a language understandable for the student, and the criteria of success.

• The lecturer asks the pupils to put photographs taken in the notebooks and write out the characteristics of the pine. The teacher monitors the students' work and checks the correctness of the task.

• The teacher asks students what environmental factors (biotic and abiotic) affect the pine's life. He recommends the charges to write them in notebooks.

Realization

• Students read the fragment entitled „Adaptation of pine to environmental conditions” and explain when the pine produces long roots, tall or low stems, spreading or small crowns, why its bark and woody momentum.

• Students use the interactive board to organize their knowledge.

• The teacher presents two sheets of a paper towel and moistens them lightly. One leaves unfolded, the other curls into a tight tube. He asks students which sheet will lose water faster. Then he asks his pupils to explain why the pine has needle‑shaped leaves. The instructor draws attention to the layer of wax on the surface of the needles, and then on the board showing the cross‑section of the pine needle indicates the arrangement of the skin cells and the thickness of their walls. He asks students to discuss the relationships of construction and function.

• Students read the fragment entitled „Pine propagation” and analyze interactive illustrations depicting cones. The teacher asks selected people to explain why pine produces pollen and how it is transferred to female cones.

• The lecturer distributes pine seeds to the pupils. Instructs students to describe the outer structure of seeds and conduct „Observation 1”.

• The teacher asks students what it means that the pine is a wind and wind plant. It asks for its adaptations related to these properties.

• The teacher instructs the pupils to answer the question in writing, on what basis it can be stated that the pine reproduces sexually. Volunteers read their answers. The teacher assesses their correctness, noting whether the students have included in them the statements about the embryo of the plant resulting from the merging of germ cells.

Summary

• The teacher asks students to carry out the recommended interactive exercise themselves.

• The teacher displays the criteria for success and asks the students to assess their skills acquired during the classes.

Homework

• Listen to the abstract recording at home. Pay attention to pronunciation, accent and intonation. Learn to pronounce the words learned during the lesson.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Adaptation of pine to environmental conditions, reproduction of pine

Pine is a common gymnosperm. Pine trees create pinewood on sandy, poor soils of central and northern Poland. Due to massive roots growing deep into the soil and thick lignified stems, pine can grow tall and is resistant to wind. Pine stem, called trunk, supports the branches growing in regular intervals. Together, they form the tree crown. The shape of a trunk and crown (tree form) depends on the amount of light reaching a plant. Pines growing in dense stands have tall, slim trunks and small crowns. These are specimens which, due to their ability to grow fast, overcame the competition which grew slowly to the light. Other trees, and even own branches of pines, were shadowed by such pines, and therefore they lost needles and died. Contrary to the trees growing in a forest, the stand‑alone pines growing in full sunlight are not tall, and they have branchy, dense crowns supported by a short, thick trunk.

The leaves of the scots pine (Pinus sylvestris) have the form of narrow and quite long grey‑blue needles which grow in pairs from shortened shoots (dwarf shoots). The length and quantity of needles are important features which form the basis for distinction of pine species. The pine needles are evergreen, therefore they can perform photosynthesis also during winter.

The structure of needles of majority of gymnosperm trees in temperate and cold climate is the adaptation to the conditions of drought and frost. Their shape is a result of reduction in surface area – it limits the evaporation of water from leaves. They are covered with thick epidermis protected with the layer of wax, protecting the leaves from excessive loss of water. It helps these plants in surviving long winter months when it is impossible to draw water from the frozen soil.

Thick bark protects the trunks against the activity of severe frosts and drying up, and against mechanical damage. There are numerous channels running through the trunks of coniferous trees and their needles which produce resin – a substance used by the plants for sealing the damages. Gymnosperms, such as pine, may reach big size thanks to well‑formed mechanical tissues which stiffen tall stems, and thanks to conducting tissues able to transport water up to the top of a tree.

Pine trees reproduce by sexual reproduction. Gametes are produced in female and male cones. In May, on the top of young sprouts small, reddish cones appear, composed of tiny scales. There are two ovules on each scale. Ovules contain female gametes. At the base of other young branches there are small, egg‑shape male cones. They produce vast amounts of light yellow pollen which contains male gametes. After tipping out the pollen, male cones dry up and come off.

During the pollen time of pine trees, the pollen grains fall on everywhere, sometimes in a big distance from the tree. Some of them land on the ovules. Then, male gametes can combine with female gametes, and fertilisation takes place. An embryo of a new plant is developed from a fertilised egg cell. It takes place in an ovule, which turns into a seed after some time. During this time, female cones grow and lignify, and seeds develop and become mature. This process takes three years. Both the ovules and seeds are uncovered – they lie on the scales of cones, without any protection covering them. That is why the plants such as pine tree are called gymnosperms.

Pine is an anemophilous plant because the grains of pollen are transported by wind. Anemophilous plants produce enormous amounts of pollen which lands on the ovules by accident. This method of pollination is effective because pollen is small and it has structures making it easier to lift it. In the case of pine tree, pollen grains have two bubbles filled with air. Pollen produced on high part of a tree has a Chance to be transported over long distances. Also the distribution of female cones in the external part of a tree crown is the adaptation to anemophily.

Seeds of scots pine are also transported by wind, and therefore this plant is described as anemochorous. Seeds are tiny, light, and they have wings which lengthen the time of landing on the ground. Gusts of wind may transport them over long distances from a tree on which they were produced. Then, the seedlings which germinate from the seeds do not have to compete with a parent plant for sunlight or water.

Seeds protect their valuable content better than the spores. A spore is a single cell adapted to survive difficult conditions. A seed is composed of, apart from an embryo, a spare tissue which can be used by an embryo, and a thick, resistant testa.

• Pine is a common gymnosperm.

• Pine stem, called trunk, supports the branches growing in regular intervals. Together, they form the tree crown. The shape of a trunk and crown (tree form) depends on the amount of light reaching a plant.

• Pines are anemophilous and anemochorous.