Topic: Parenchymal tissues

Target group

5th‑grade students of elementary school

Core curriculum

5. Variety and unity of plants:

1) plant tissues – the pupil observes and recognizes (under a microscope, in the diagram, in the picture or on the basis of the description) plant tissues and indicates their adaptive features to perform specific functions (creative, covering, parenchyma, strengthening, conductive tissue);

General aim of education

Students discuss the structure and function of parenchymal tissues

Key competences

• communication in foreign languages;

• digital competence;

• learning to learn.

Criteria for success
The student will learn:

• recognize plant tissues;

• discuss the basic functions of individual plant tissues;

• show the relationship between the structure of tissues and the function they perform;

• microscopic observation of plant tissues.

Methods/techniques

• expository

  • talk.

• activating

  • discussion.

• exposing

  • exposition.

• 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;

• Elodea stem;

• pear;

• potato bulb;

• equipment for microscopy;

• Lugol's liquid;

• microscope;

• magnifying glass;

• microscopic preparations prepared by the teacher: cross‑section of the urea stem and cross‑section of the dicotyledonous plant leaf.

Lesson plan overview

Before classes

• 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.

Introduction

• The teacher explains the aim of the lesson and together with students determines the success criteria to be achieved.

Realization

• The instructor shows on the silhouette of the pear how the plane of the cross‑section and longitudinal section run..

• Students look under the microscope cross‑section of a dicotyledonous plant leaf. The teacher instructs them to draw a diagram of the tissue arrangement in the leaf. Students identify on the microscopic image the tissue covering the leaf (upper and lower epidermis) and absorption parenchyma, i.e. the type of parenchyma in which the photosynthesis process takes place..

• Students draw three adjacent cells of the palisade crumb and three adjacent skin cells, trying to reflect the differences between these tissues. After the expiration of the time they present their work and describe the discrepancies in the structure of the cells of the epidermis and cells of the absorption parenchyma. The teacher indicates the best‑made drawings.

• Participants familiarize themselves with the content presented in the interactive illustration. Then the teacher discusses the issues with the students.

• Students get pairs and carry out „Observation 1”. Microscope also tests the cross‑section of the Elodea stems. Microscopic observations are documented by drawings, they record observations and conclusions.

• Students carry out the interactive exercises checking the level of knowledge learned during the lesson. The teacher initiates a discussion during which the correct solutions for all the exercises performed by the students are discussed.

Summary

• At the end of the class, the teacher asks the students questions:

  • What did you find important and interesting in class?

  • What was easy and what was difficult?

  • How can you use the knowledge and skills you have gained today?

  Willing/selected students summarize the lesson.

Homework

• Imagine that you have the opportunity to interview an academic - a specialist in the field of today's lesson. What questions would you like to ask him? Write them down.

The following terms and recordings will be used during this lesson

Terms

Texts and recordings

Parenchymal tissues

The main body mass of the plant is parenchymal tissues. The cells of these tissues are usually large, thin‑walled and loosely arranged. Between them there are free spaces called intercellular spaces. Depending on the function, four types of parenchyma are distinguished:

• chlorenchyma occurring in all green parts of the plant, mainly in the leaves; its cells contain a lot of chloroplasts, which makes it possible to carry out photosynthesis;

• basic parenchyma filling the entire interior of the plant; its living cells are loosely arranged and contain large vacuoles; occur in stems, roots, fleshy fruits;

• storage parenchyma storing food substances and water; is found in stems, roots and in plant seeds;

• aerenchyma characteristic for aquatic and marshy plants; its cells are separated by spaces filled with air, which facilitates the raising of leaves and stalks on the surface of water, and enables the storage of oxygen and carbon dioxide.

• The body of plants is filled with tissues, i.e. assemblies of cells with a similar structure specialized to perform specific functions.

• The parenchyma fills the spaces among other tissues, stores the substances produced by the plant, and when it has chloroplasts – conducts photosynthesis.