Topics of laboratory work Gr 4 NOB – 22
Lab session 1.
Topic: Cell and tissues. The structure of a plant cell.
goal : to study the structure of the microscope, to master the technique of working with it. To study the features of the external and internal structure of the cell.
Equipment : microscopes, Petri dishes, slides and coverslips, a glass of water, napkins, ready-made preparations “Onion peel”, “Geranium leaf epidermis”, potato tuber.
Progress of work :
1. Get acquainted with the device of the microscope and the method of working with it. Determine the magnification of the microscope.
2. Examine the onion skin cells under low magnification. Draw a cell. Sign organelles: nucleus, membrane, cytoplasm, vacuole.
3. Examine the preparation “Geranium leaf epidermis” under a microscope. Pay attention to the differences in cell shapes, their color. Sign the hair, the main cells of the epidermis, stomata, chloroplasts.
4. Make a temporary preparation of potato tuber storage cells. Look at the shape of the cells under a microscope. Sketch a cell filled with starch grains. Pay attention to the shape and internal structure of the starch grain, sketch it.
Tasks for independent work :
1. Study the structure of a plant cell and tissue.
2. Answer in writing the questions:
one). What is photosynthesis?
2). What are the functions of plant cell plastids?
3). How is potato starch formed?
4). What organelles have an inner membrane?
5). What is the function of a vacuole?
6). What plastids can chloroplasts turn into?
7). What are the similarities and differences between animal and plant cells?
eight). What are the 4 types of meristematic (educational) tissues?
nine). What organs are covered by the epidermis?
10. What are guard cells? Where are they located? Do they have chlorophyll?
11. What are lentils? What is their function?
12. What are tracheids and vessels? What are their functions?
13. What is the function of sieve tubes?
14. What histological elements are included in the composition of xylem (wood), phloem (bast)?
15. What are the functions of excretory tissues in plants? How does a person use milky juice, resins, essential oils?
3. Fill in the table. one
Differences between photosynthesis and respiration
|1. What substances are absorbed?|
|2. What substances are obtained?|
|3. Is light necessary?|
|4. In what organelles does it go?|
|5. In what organisms is it possible?|
|6. Energy is absorbed or released|
4. Fill in table 2. “Tissues of a plant organism”
|Type of fabric||Location||Structural features||Functions|
5. Make a conclusion about the presence of tissues, their different structure and answer the questions:
– How is the structure of the tissue related to the function performed?
– Why are the cells of the integumentary tissue closely adjacent to each other?
– How to distinguish the main tissue from the integumentary?
Lab session 2.
Topic: The structure of the vegetative organs of plants.
goal : to study the external and internal structure of the leaves, stems, roots of flowering plants. To get acquainted with the types of root systems and the structure of shoots.
Equipment : microscopes, magnifiers, napkins, prepared preparations, herbarium of woody dicotyledonous plants, tables.
Progress of work :
1. On the herbarium and tables, consider the structure of the shoots of woody plants. Draw the external structure of the shoot. Sign the stem, leaf, leaf axil, buds (apical, axillary), node, internode.
2. Examine the preparation “Camellia Leaf” under a microscope. Draw a cross section of a leaf. Label the upper and lower epidermis, stomata, mesophyll, columnar and spongy tissues, intercellular spaces, vascular bundle (vein).
3. Examine the preparation “Linden Branch” under a microscope. Draw a diagram of the transverse structure of the stem of a woody plant. Sign the bark, cambium (xylem), wood, pith, cork, phloem (bast), growth rings.
4. Draw a diagram of the internal structure of a herbaceous plant (clover or corn). Label the epidermis, primary cortex, pith, vascular fibrous bundles (pay attention to their location), phloem, xylem, cambium (in clover).
5. Draw a cross section of the root in the suction zone. Label root hairs, primary cortex, epiblem, central cylinder, xylem (vessels), phloem (sieve tubes).
Tasks for independent work :
1. To study the types of dissection of the leaf blade of simple and the shape of complex leaves. Draw their schemes in the form of a table. Give examples of plants.
2. Fill in the table. 5.
Features of the structure of life forms of plants
|Location of vascular tissues in the stem|
|Type of integumentary tissue|
3. Define the concepts : fibrous, tap root system, main root, lateral and adventitious roots.
4. Sketch in a notebook for laboratory work : 1 woody plant, 1 herbaceous monocot and 1 herbaceous dicot.
5. Answer in writing the questions:
one). How to distinguish leaf and shoot modifications similar in appearance?
2). How is the annual ring formed?
3). Why do plants need phloem, xylem, cambium, cork?
4). What is mycorrhiza, rhizosphere? How are nodules formed on the roots of legumes?
5). What modifications of roots are found in plants and what functions do they perform?
6). What is called pollination? List the types and methods of pollination. Give examples.
7). Explain what the expressions “bisexual”, “unisexual”, “asexual” flowers, “monoecious and dioecious” plants mean, give examples.
eight). What are inflorescences and what is their biological role? What signs of the structure of inflorescences are taken into account for their classification?
nine). What is a fruit? Briefly describe the structure and biological significance of the fruit. From what and how is the fetus formed? Principles of fruit classification. What is called infertility. Describe the methods of dispersal of fruits and seeds.
ten). The concept of “vegetative reproduction”. Natural vegetative propagation of seed plants by specialized and non-specialized organs.
6. Make a conclusion.