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GENERAL BOTANY

LABORATORY MANUAL

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Prepared by

Prof. Lydia Capiral – Plaza

 

 

 

 

TABLE OF CONTENTS

 

 

 

The Microscope

Act. 1: Parts, Care and Operation of the Microscope

Report Sheet No. 1

 

The Plant Cell

Act. 2: The Living Plant Cell

Report Sheet No. 2

 

Cell Division

Act. 3: Mitosis

Report Sheet No. 3

 

Transport in Plant Cells

Act. 4: Passive Transport in Plant Cells

Report Sheet No. 4

 

Primary Tissues

Act. 5: Primary Tissues

Report Sheet No. 5

 

Root Morphology and Physiology

Act. 6: Root Morphology

Report Sheet No. 6

Act. 7: Growing Plants Without Soil

Summary of Observations

 

Stem Morphology and Physiology

Act. 8: Morphology and Anatomy of Stems

Report Sheet No. 8

Act. 9: Xylem Conduction

Report Sheet No. 9

 

Leaf Morphology and Physiology

Act. 10: Morphology and Anatomy of the Leaf

Report Sheet No. 10

Act. 11: External Features of Different Kinds of Leaves

Report Sheet No. 11

Act. 12: Physiological Processes in Leaves

Report Sheet No. 12

Act. 13: Pigment Separation by Paper Chromatography

Report Sheet No. 13

 

Act. 14: Tests for Reserve Food in Plants

Report Sheet No. 14

 

Flowers, Fruits, and Seeds

Act. 15: Flower Structure

Report Sheet No. 15

Act. 16: The Fruits

Report Sheet No. 16

Act. 17: Seeds

Report Sheet No. 17

 

The Herbarium

Act. 18: Preparation of Herbarium Specimens

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

THE MICROSCOPE

 

Much of the laboratory work in General Botany I involves the study of minute structures which are invisible of poorly seen with the naked eye. This requires the use of the microscope, the primary purpose of which is to magnify or greatly enlarge the image of the objects or organisms so their detailed structures may be studied. For our purposes, the monocular compound microscope will be used. It is an optical instrument with two lens systems:  the objectives and the eyepiece or ocular. It can magnify an image up to several hundred times the actual size of an object. For effective use and proper care of the microscope, one must become familiar with its construction, parts and uses. There are three sets of parts: namely, the mechanical, illuminating, and magnifying parts.

 

  1. Mechanical Parts

 

1.      Base- the U-shaped structure on which the microscope firmly rests in the place.

2.      Pillar- the post of vertical extension of the base and to which the arm is attached.

3.      Arm- the curve structure that connects the base and the body tube which serves as the handle of the microscope and at the same time supports the optical instrument.

4.      Inclination joint- a movable hinge that attaches the frame of the microscope to the base and is used for tilting the microscope whenever necessary.

5.      Stage- the platform upon which the slide containing the specimen to be studied is placed and is provided with a central opening allowing light to pass from below into the object of study.

6.      Substage- found below the stage and holds the Abbe condenser above and the iris diaphragm below.

7.      Body tube- a hollow cylinder that serves as attachment of the draw tube into the microscope as well as passage way of light from the objective to the ocular.

8.      Draw tube- the smaller cylinder that is attached to the upper part of the body tube and holds the ocular.

9.      Revolving nosepiece- attached to the base of the body tube and holds the objectives and is protected by a fixed dust shield that keeps off the dust from the objective lenses.

10. Adjustment knobs- consisting of two pairs of knobs which when turned clockwise and counterclockwise, lower of raises the body tube respectively. These are used to adjust the objectives when focusing.

a.      Course adjustment knobs- the upper larger knobs used for faster movement of the body tube when focusing the LPO.

b.      Fine adjustment knobs- the smaller knobs used for slow or little movement of the body tube when focusing the HPO.

 

  1. Illuminating Parts

 

1.      Mirror- the double-faced mirror (plane of flat on one side and concave on the other) is used to reflect light through the object, lenses and into the eye. The frame is held by the mirror rack or fork provided with double hinge to facilitate tipping to any desire angle.

a.      Plane mirror- used when the source of light is very bright (as natural light, sunlight)

b.      Concave mirror- used when the source of light is of low intensity.

2.      Condenser (Abbe Condenser)- the lens held in place by a rack or fork mounted in the substage and is used to condense or concentrate the reflected light form the mirror to the object or specimen being examined.

3.      Iris diaphragm- provided with a lever which can be manipulated to close or open the diaphragm, thus, regulating the amount of light that passes through the lenses into the observer’s eyes.

 

  1. Magnifying Parts

 

1.      Eyepiece or ocular- the detachable cylinder situated on top of the draw tube which is equipped with one set of lenses that magnifies the object several times and enables one to see the specimen by looking through it. Along the draw side of the tube, the magnification number of the ocular is indicated. It is provided with a pointer which is used to pointing at the specific parts of the specimen.

2.      Objectives- there are three of these attached to the revolving nosepiece. These are the scanner, the low and the high power objectives. Their magnification numbers are indicated at the side of the objectives. Their magnification numbers are indicated at the sides of the objectives.

a.      Scanner- the shortest cylinder or tube with very large lens openings. It is equipped with a large lens opening for low magnification and is used to observe a much wider field of the object.

b.      Low power objective (LPO)- the shorter cylinder or tube with a relatively large lens opening. It is equipped with a large set of lenses with lower magnifying power, and is used in observing the general outline and locating the various parts of the specimen.

c.      High power objective (HPO)-  the longer cylinder or tube with a small lens opening. It is equipped with a smaller set of lenses with higher magnification power and is used to study the detailed parts of the specimen.

 

The total enlargement or magnification of the specimen is determined by simply multiplying the magnification of the eyepiece by the magnification of the objective being used. This gives the linear magnification of the lenses which gives the total lens magnification of the object or specimen.

The lower the magnification, the lesser is the amount of light needed to the specimen but the greater the depth or thickness of focus and size of the field.

 

CARE OF THE MICROSCOPE

 

    1. When getting the microscope from the cabinet, hold it firmly by the arm with one hand and support it at the base with your other hand, the palm directly positioned under the mirror.
    2. When carrying the microscope, hold it in front of you with its side close to your body for greater stability.
    3. Do not tamper with any part of the microscope. If it does not seem to function properly, report immediately the matter to your instructor or to the laboratory technician in-charge of the microscope.
    4. Never touch the lenses with your fingers for even if your hands are clean, slight perspiration will injure the lenses.
    5. Always, keep the lenses clean. Brush off the dust particles with a lens paper or even a tissue paper.
    6. Do not touch the mirror with your fingers. Handle it by the frame to tip it at any desired angle.
    7. Clean the rest of the microscope with clean, soft, linen cloth.
    8. Never allow liquids, particularly acids and alcohol to come in contact with any part of the microscope. Always use a cover glass when examining fresh mounts in water. Do not incline the microscope when examining fresh mounts.
    9. Unless necessary, do not incline the microscope, otherwise the inclination joint will eventually come loose.
    10. When regulating the diaphragm, never force its lever to the full limit in either direction, otherwise, its delicate leaves may be damaged.
    11. Before returning the microscope the storage cabinet, be sure that:

a.      It is in an upright position with the lower power objective or scanner in place.

b.      The body tube is lowered by the objective does not touch the condenser

c.      The stage clips are positioned in the forward direction

d.      The diaphragm is wide open

e.      The mirror is tipped to a vertical position facing forward.

 

 

 

 

 

 

Activity 1

Parts, Care, and Operation of the Microscope

 

I.                    Objectives:

 

To be able to:

 

1.      identify the parts of a monocular compound microscope

2.      enumerate the uses of each part

3.      draw and label correctly the parts of the microscope

4.      list several ways by which one can take care of the microscope

5.      become familiar with essential principles of microscope use

6.      improve the students’ technique of microscope use through practice

 

II.                  Materials:

 

Monocular compound microscope

Glass slide

Cover slip

Medicine dropper

Small letter “e” from a newspaper

 

III.                Procedure

 

A.     Identifying Parts of the Microscope

 

1.      Borrow a monocular microscope and gently set it at least one inch from the edge of the table.

2.      Examine the parts and identify them correctly.

 

B.    Making a Temporary Mount

 

1.      Make a wet mount of the smallest letter “e” in the newspaper and mount this in an upright position in a drop of water placed on a glass slide.

2.      Cover this with a cover slip.

3.      Place the slide directly above the opening of the stage. Use stage clips to keep the slide in place.

 

C.    Operation of the Microscope

 

1.      Turn the revolving nosepiece clockwise until the LPO is in place.

2.      Adjust the mirror and regulate the opening of the iris diaphragm to the maximum amount of light.

3.      While looking on one side of the microscope, use the course adjustment to lower the body tube until the objective is about 16 mm. above the cover slip.

4.      While looking through the ocular, use the course adjustment to raise the body tube until the outline of the object comes into view. A sharp, clear image may be obtained by focusing with the fine adjustment.

5.      For greater magnification, turn the nosepiece until the HPO is in place. A distinct focus may be obtained by focusing with fine adjustment.

6.      Move the slide on the stage up and down, then from left to right. Take note of the direction of the movement of the image.

 

IV.               Drawings:

 

1.      Draw the microscope in its lateral view at the eye level reducing it to one half of its actual size (Fig. 1.1). Label the parts correctly.

2.      Make a drawing of the letter “e” as seen (Fig. 1.2)

a.      with the naked eye

b.      under the LPO

c.      under the HPO

 

V.                 Questions:

 

1.      What is a monocular compound microscope?

2.      What is the proper way of holding the microscope?

3.      When is the concave mirror used? The plane mirror?

4.      What are the points to remember before returning the microscope?

5.      When you move the slide on the stage up and down, and from left to right, in what direction does the image of the object move in each case?

6.      When you change form LPO to HPO:

a.      Was there an increase or a decrease in the area of the image in the field?

b.      Was there a change in the position of the image?

 

 

 

 

 

 

 

 

 

 

 

 

Report Sheet No. 1

Parts, Care, and Operation of the Microscope

 

 

Name: _______________________________ Date Performed: _____________

Time: ___________                                                 Rating: ____________________

 

 

 

 

Fig. 1.1 A MONOCULAR COMPOUND MICROSCOPE

 

Fig 1.2 LETTER “e” AS SEEN:

 

 

 

 

 

 

With the naked eye                           under the LPO                            under the HPO

 

 

Answer to the questions:

 

1. What is a monocular compound microscope?

 

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

2. What is the proper way of holding the microscope?

 

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

3. When is the concave used?

 

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

3. 2. When is the plane mirror used?

 

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

4. What are the points to remember before returning the microscope?

 

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

5. When you move the slide on the stag up and down, and from left to right, what direction does the image of the object move in each case?

 

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

6. When you changed from LPO to HPO:

 

a. Was there an increase of decrease in the area of the image in the field?

 

_______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

b. Was there a change in the position of the image?

 

_______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

 

 

 

 

 

 

 

 

 

 

 

THE PLANT CELL

 

Organisms which belong the Kingdom Plantae are eukaryotes; they posses membrane-bounded cellular organelles, including the nucleaus. Cells are basically the same, whether that of the plant, animal, fungus, or bacterium but they do vary in size and shape, and more importantly, in the cellular organelles that may be present. Listed below is an outline of the cellular organelles found in the eukaryotic plant cells.

 

I. Cell Wall

 

A. Primary Cell Wall

B. Middle Lamella

C. Secondary Cell Wall

 

II. Protoplasm

 

A. Nucleus

1. nuclear membrane

2. nucleoplasm or nuclear sap

3. chromatin

4. nucleolus

 

B. Cytoplasm

1. plastids

a. chloroplasts

b. chromoplasts

c. amyloplasts

d. leucoplasts

2. mitochondrion

3. dictyosomes

4. endoplasmic reticulum

5. ribosomes

6. spherosomes

7. microbodies

8. microfibrils

9. tonoplasts

10. plasmalemma

11. crystals

12. plasmodesmata

 

 

 

 

 

Each of the organelles listed below has a characteristic structure and performs the same general function in all plant cells. It is important to note that some structures present in animal cells are not found in plant cells are vice versa. Below is a list of the fundamental differences between plant and animal cells.

 

 

Plant Cell

Animal Cell

Lysosomes

Absent

Present

Centrosomes

Absent

Present

Plastids

Present

Absent

Outer covering

Cell wall

Plasma membrane

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Activity 2

The Living Plant Cell

 

I. Objectives:

 

To be able to:

 

1. identify the main parts of a living plant cell

2. draw a cell of each of the required specimens and label correctly the parts seen under the microscope

 

II. Materials:

 

Compound microscope

Empty glass slide

Cover slip

Medicine dropper

Sharp blade

Iodine solution/ methylene blue

Fresh mount of the epidermis of:

Allium cepa (onion bulb)

Cucurbita maxima (shoot of squash)

Hydrilla verticillata (digman)

Solanum tuberosum (potato tuber)

Solanum melongena (eggplant)

Lycopersicon lycopersicum (tomato)

Capsicum frutescens (red pepper)

 

III. Procedure:

 

A. Allium cepa

 

From the epidermis of the inner layer of the onion scale, prepare a temporary mount of it in water. Examine one cell under the LPO, then shift to HPO, and answer the following:

 

1. Is a nucleus found in every cell?

2. Is the cell wall uniform in thickness?

3. Are the primary and secondary cell walls visible?

4. What is the color of the plastids, if present?

5. Are intercellular spaces present between and among the cells?

6. Do you oberve any protoplasmic streaming in the cells?

 

 

 

 

B. Cucurbita maxima

 

Scrape off a few hairs (trichomes) from a squash shoot. Be sure to include a very thin layer of epidermal cells of the stem to get the living cells. Observe under HPO.

 

1. How many cells are contained in each trichome? Get the average number.

2. Enumerate structures which are clearly visible.

3. Are the cytoplasmic structures moving?

4. Do you find any plastids? If so, what is the color of the pigment present?

 

C. Hydrilla maxima

 

Put a drop of water on a glass slide. Get a leaf somewhere near the tip of the Hydrilla plant. Place a cover slip and examine under the HPO.

 

1. Why is the Hydrilla leaf colored green?

2. What do you call these green structures that contain the green pigment?

3. Are they distributed throughout the interior of the cell or are they restricted to a layer next to the cell wall?

4. What is their shape?

5. Do you observe any movement in the cell?

6. What structures are moving?

7. Note the direction of the movement. What is the term given to this movement?

8. Do chloroplast move from one cell to another/

 

D. Solanum melongena, Lycopersicon lycopersicum, Capsicum frutescens

 

Make surface sections of the highly colored epidermal cells of the specimens listed above. Examine under the HPO.

 

1. What pigments are present in these sections?

2. How do these pigments differ from those of the Hydrilla and onion bulb?

 

E. Solanum tuberosum

 

Cut a very thin slice of the interior of a potato tuber. Place a slice and a drop of water on a glass slide, add a cover glass and examine microscopically. Focus on a region that is only one layer of cells in thickness.

 

1. Are inclusions present?

2. If so, of what type are they?

Add iodine solution on the slide, close to but not on the coverglass. Draw out the iodine solution under the coverglass applying a small piece of tissue paper to the opposite edge?

 

3. What is the composition of the granules?

 

IV. Summary of the Observation:

 

In a tabulated form, identify:

 

1. shape of cell from each specimen

2. kind of plastids present

3. pigment found on each

 

V. Drawings:

 

Make a magnified drawing of each of the following as viewed under the HPO. Label all visible parts.

 

A single cell of:

 

a. Allium cepa (Fig. 2.1)

b. A trichome and the basal cell of the trichome of Cucurbita maxima (Fig. 2.2)

c. Hydrilla leaf; indicate arrows the movement of the cytoplasmic content (Fig. 2.3)

d. The outer epidermis of the specimens listed in Procedure D. (Fig. 2.4)

e. Inclusion found in Tuberosum (Fig. 2.5)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Report Sheet No. 2

The Living Plant Cell

 

Name: _______________________________  Date Performed: _____________

Time: ______________                                          Rating: ____________________

 

A. Allium cepa

 

 

Fig. 2.1 A single cell of Allium cepa

 

1. Is a nucleaus found in every cell?

 

________________________________________________________________________________________________________________________________

 

2. Is the cell wall uniform in thickness?

 

________________________________________________________________________________________________________________________________

 

3. Are the primary and secondary cell walls visible?

 

________________________________________________________________________________________________________________________________

 

4. What is the color of the plastids, if present?

 

________________________________________________________________________________________________________________________________

 

5. Are intercellular spaces present between and among the cells?

 

________________________________________________________________________________________________________________________________

 

6. Do you observe any protoplasmic streaming in the cells?

 

________________________________________________________________________________________________________________________________

B. Cucurbita maxima

 

 

Fig. 2.2 A basal cell of a trichome, Cucurbita maxima

 

1. How many cells are contained in each trichome? Give the average number.

 

________________________________________________________________________________________________________________________________

 

2. Enumerate the structures which are clearly visible.

 

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

3. Are they distributed throughout the interior of the cell or are they restricted to a layer next to the cell wall?

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

4. What is their shape?

 

________________________________________________________________________________________________________________________________

 

5. Do you observe any movement in the cell?

 

________________________________________________________________________________________________________________________________

 

6. What structures are moving?

 

________________________________________________________________________________________________________________________________________________________________________________________________

7. Note the direction of the movement. What is the term given to this kind of movement?

 

________________________________________________________________________________________________________________________________

 

8. Do chloroplasts move from one cell to another?

 

________________________________________________________________________________________________________________________________

 

D. Solanum melongena, Lycoperiscon lycopersicum, Capsicum frutescens

 

 

 

 

 

 

         Solanum cell                            Lycopersicon cell                       Capsicum cell

 

1. What pigments are present in these sections?

 

________________________________________________________________________________________________________________________________

 

2. How do these pigments differ from those of the Hydrilla and Allium cepa?

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

E. Solanum tuberosum

 

 

       Fig. 2.5. A single cell from Solanum

1. Are inclusions present?

 

________________________________________________________________

 

2. If so, what type are they?

 

________________________________________________________________

 

3. What is the composition of the granules?

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

F. Summary of Observations

 

 

Shape of the cell

Plastids present

Pigments present

1. Allium cepa

 

 

 

2. trichome of Cucurbita

 

 

 

3. Hydrilla

 

 

 

4. Solanum melongena

 

 

 

5. Lycopersicon

 

 

 

6. Capsicum

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CELL DIVISION

 

Growth is a result of 1) cell division, which increases the number of cells that generally brings about an increase in the size of the organism and 2) cell elongation. Cell division makes possible tissue specialization for the different structural and physiological activities including absorption, conduction, reproduction, photosynthesis, and support. It is centered about the nucleus but the cytoplasm also undergoes changes during the entire process. Plants have their greatest activities in cell division, in spore production, in stem and root and in the meristems of the cambium, cork cambium, and pericyle.

 

In the laboratory, in order to see the progressive steps which occur during mitosis, the tissues of the root tip (especially of the Allium cepa) are cut by means of a microtome to a thinness of 10 to 15 microns and stained with variety of dyes to achieve contrast in the cellular organelles. For convenience in discussing the entire process of cell division, it is generally thought of as having five phases but one must bear in mind that mitosis is a continuous process.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Activity 3

Mitosis

 

I. Objectives:

 

To be able to:

 

1. construct a diagram that depicts the stages of plant mitosis

2. name the principal events that characterize each period and phase

3. identify and explain the significance of each of the stages of mitosis

 

II. Materials:

 

Compound microscope

Prepared slides of Allium cepa mitosis

 

III. Procedure:

 

1. Examine a section of the Allium cepa root tip under the LPO. Then shift to HPO for a detailed study of the different stages.

2. Look for the cell in the process of cell division; identify the stages and observe the following: spindle fibers, chromosomes, cell plate, equator, and poles.

3. After drawing each of the different stages, summarize that occur in each.

 

IV. Drawings:

 

1. Make at least one drawing of each of the following stages as observed under the microscope:

a. Interphase or resting cell (Fig. 3.1)

b. prophase (Fig. 3.2)

c. metaphase (Fig. 3.3)

d. anaphase (Fig. 3.4)

e. telophase (Fig. 3.5)

 

V. Questions:

 

1. What is mitosis?

2. What is its significance?

3. Suppose a nucleus contains 4 chromosomes, how many chromatids would each possess at prophase?

4. How many chromosomes would be distinguishable at anaphase? Why?

5. What marks the initiation of cytokinesis in plant mitosis?

6. What is the direction of the division of the cytoplasm?

 

 

Report Sheet No. 3

Mitosis

 

Name: __________________________ Date Performed: __________________

Time: _______________                            Rating: __________________________

 

Drawings:

 

 

Events

 

 

Fig. 3.1

 

 

 

Fig. 3.2

 

 

 

Fig. 3.3

 

 

 

 

Events

 

 

Fig. 3.4

 

 

 

Fig. 3.5

 

 

Answer to questions:

 

1. What is mitosis?

 

________________________________________________________________________________________________________________________________

 

2. What is its significance?

 

________________________________________________________________________________________________________________________________

 

3. Suppose a nucleus contains 4 chromosomes, how many chromatids would each possess at prophase?

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

 

4. How many chromosomes would be distinguishable at anaphase? Why?

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

5. What marks the initiation of cytokinesis in plant mitosis?

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

6. What is the direction of the division of the cytoplasm?

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TRANSPORT IN PLANT CELLS

 

Substances necessary for normal growth and development of plants must continually be transported into cells while metabolic wastes must be eliminated so that they won’t accumulate inside the cells. For instance, water as well as mineral salts from the soil solution enter root cells while carbon dioxide and oxygen through tiny pores known as stomata in leaves and lenticels in stem. Excess oxygen not utilized during cell respiration as well as oxygen produced during photosynthesis is released to the atmosphere. In most cases, movement of these substances is along a concentration gradient, that is, from regions of greater concentration to regions of less concentration. Such type of transport is known as passive transport. Diffusion is a type of transport which is concerned with the movement of solute particles. Aside from concentration gradient, factors affecting the rate of diffusion include the temperature, size of diffusing molecules and presence of other molecules aside from the diffusing one. Osmosis, on the other hand, is another type of passive transport, which is involved in the movement of solvent (e.g. water) through a semi-permeable membrane. In osmosis, the presence of a differentially permeable membrane as well as differences in the concentration of the medium and the intracellular substance (i.e. cell sap) are factors to consider in determining the direction of water flow.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Activity 4

Passive Transport in Plant Cells

 

I. Objectives:

 

To be able to:

 

1. Perform and observe the process of diffusion and osmosis.

2. give an operational definition of:

a. osmosis                 c. turgor pressure

b. diffusion                 d. plasmolysis

3. list at least three practical applications for each.

 

II. Materials:

 

A.                                                                    C.

 

Test tube                                                        Fresh specimens of:

Glass rod sealed at one end                                   lettuce leaf

Cork                                                                            slice of cucumber

Potassium permanganate                                       stem of celery

Water                                                                          beaker with strong saline

 solution

                                                                                    Dish of water

B.

 

Leaf of Rhoeo discolor

Blade

Glass slide

Cover slip

Coumpound microscope

Distilled water

.5 saline solution

.9 saline solution

1.5 saline solution

 

III. Procedure:

 

A. Diffusion

 

1. Fill a test tube with a solution of potassium permanganate

2. Fill a glass rod sealed at one end with water and invert it over the test tube with its open end just below the surface of the potassium permanganate solution.

3. Observe after 2 hours.

4. Answer guide questions listed after each part of the procedure has been done.

 

 

B. Osmosis

 

1. Strip off a thin layer of the outer epidermis of the undersurface of the leaf of Rhoeo discolor

2. Place a drop of distilled water on a microscope slide.

3. Add a cover glass and examine under the LPO, then HPO.

4. Focus on the stomata and observe the condition of the guard cells.

5. Apply a small piece of blotting or tissue paper on the edge of the cover slip to remove the water.

6. Place a drop of .5 saline solution on the slide, close to but not on the cover slip.

7. Draw the solution out under the cover slip by applying again a small piece of tissue paper to the opposite edge.

8. Examine under the HPO and observe the changes in the guard cells.

9. Repeat procedure number 6 to 8, but this time use the .9 saline solution; after which 1.5 saline solution follows.

10. Fill up the table on page 25.

11.Draw

a. Fig. 4.1 guard cell in distilled water

b. Fig. 4.2 guard cell in .5 saline solution

c. Fig. 4.3. guard cell in .9 saline solution

d. Fig. 4.4. guard cell in 1.5 saline solution

 

C. Optional Activity: Diffusion of Water through a Semi-Permeable

Membrane

 

·        Subject to availability of the following chemicals:

Potassium Ferocyanide (K4FeCN)6, Copper Sulfate (CuSO4)

 

1. Fill a 50 ml beaker with a 5% solution of CuSO4

2. Place the beaker on a solid support, such as a window sill, so that it will be between you and a source of direct light, but against a dark background. The light must come from an angle so that it does not shine directly into your eyes.

3. Drop a small, transparent yellow crystal of K4Fe(CN)6 into the solution. Do not disturb or jar the beaker.  As soon as the solution of the potassium ferrocyanide comes in contact with a solution of copper sulfate, a colloidal precipitate, Cupric Ferrocyanide, Cu2Fe(CN)6 is formed. Under the condition of this experiment the precipitate forms as a membrane that separates the two solutions.

4. Observe the formation of this membrane around the dissolving crystal.

5. Note the color of the solution surrounding the crystal and retained by the newly formed membrane.

6. Note also that some point the membrane breaks.

7. Record a summary of your observations over a period of about 10 minutes.

 

D. Practical Applications of Osmosis

 

1. Place a lettuce of leaf, a slice of cucumber and a stalk of celery (if celery is not available, any fresh water can be used) in a beaker containing strong salt solution.

2. Place similar plant parts in a beaker of water.

3. After an hour, examine the plant parts and compare.

4. List your observations.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Report Sheet No. 4

Passive Transport in Plant Cells

 

Name: _______________________________  Date Performed: _____________

Time: _______________                                        Rating: ____________________

 

A. Diffusion

 

1. What was the maximum distance traveled by the potassium permanganate solution in the glass rod (in cm.)?

________________________________________________________________________________________________________________________________

 

2. Was there an increase or decrease in the level of the solution in the test tube?

________________________________________________________________________________________________________________________________________________________________________________________________

 

3. If so, record the changes in cm., in the water level.

________________________________________________________________________________________________________________________________

 

4. At the start of the experiment, which container has a higher concentration of potassium permanganate?

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

5. In what vessel was it in lower concentration?

 

________________________________________________________________________________________________________________________________

 

6. Which way did particles of potassium permanganate move during the experiment?

 

________________________________________________________________________________________________________________________________

 

7. Name the factors affecting the rate of diffusion.

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

B. Osmosis

 

 

 

 

Fig. 4.1 stomata in                            Fig. 4.2. Stomata in

     distilled water                               .5% Saline solution

 

Table 4.1

 

 

Medium

Description of Guard Cells

Classification of Medium

Direction of Water Movement

Consequences to the Cell

Distilled water

 

 

 

 

Water

 

 

 

 

0.5 saline

 

 

 

 

0.9 saline

 

 

 

 

1.5 saline

 

 

 

 

 

Note:

Description of guard cells: whether swollen, limp, flaccid, normal, etc.

Medium: isotonic, hypotonic, hypertonic

Water movement: inward, outward, or no net movement

Consequences: gained water (turgid), lose water (plasmolyzed), etc.

1. Give the empirical definition of the following:

 

a. osmosis

________________________________________________________________________________________________________________________________

 

b. diffusion

________________________________________________________________________________________________________________________________

 

c. plasmolysis

________________________________________________________________________________________________________________________________

 

d. turgidity

________________________________________________________________________________________________________________________________

 

C.

 

1. What is the color of the membrane around the dissolving crystal?

________________________________________________________________________________________________________________________________

 

2. What is the color of the solution that surrounds the crystal?

________________________________________________________________________________________________________________________________

 

3. What is the color of the solution retained by the newly found membrane?

________________________________________________________________________________________________________________________________

 

4. What happens when the fragile membrane is stretched?

________________________________________________________________________________________________________________________________

 

5. As the membrane ages, what happens to each color? Why?

________________________________________________________________________________________________________________________________

 

6. Summary and observation made a period of about 10 minutes.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

D. Practical Application of Osmosis

 

1. Describe cells of the plant parts placed in strong salt solution and in water

________________________________________________________________________________________________________________________________________________________________________________________________

 

2. Can limp cells of the plant parts be made crisp again?

________________________________________________________________________________________________________________________________

 

3. Can a plasmolyzed cell grow? Explain?

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

4. Name at least 3 practical/ physiological application of osmosis.

________________________________________________________________________________________________________________________________________________________________________________________________

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PRIMARY TISSUES

 

Tissues which form from the primary meristems, known as primary tissues, comprise the primary plant body. Below is a list of primary tissues which arise from the ground meristem.

 

A. Protoderm which differentiates into:

 

1. epidermis

 

B. Ground meristem

 

1. Cortex

2. pith

 

C. Procambium

 

1. phloem

2. vascular cambium

3. xylem

 

 

Tissues may also be classified as:

1. simple if composed of only one cell type performing a single function

2. complex if composed of several cell types performing more than one function.

 

Simply tissues include the fundamental tissues such as parenchyma, and collenchyma while the complex tissues are schlerenchyma and the vascular tissues, xylem and phloem.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Activity 5

Primary Tissues

 

I. Objectives:

 

To be able to:

1. Draw the different types of plant tissues

2. List the functions of each

3. Identify the plant tissues making up some plant organs using prepared slides.

 

II. Materials:

 

Compound microscope

Prepared slides of:

1. x-s of Ranunculus young root

2. x-s of Aristolochia old stem

3. l-s of the root tip of Oryza sativa

 

III. Procedure

 

1. Examine the lower portion of longitudinal section of a palay root tip. Take note of the apical meristems – the shape and the arrangement of the cells as viewed under the HPO.

2. Examine the slide of the cross section of Ranunculus young root the phloem, and xylem. Shift to HPO and take a close look of the shape and arrangement of the cells making up these tissues.

3. Using the slide of the cross section of the Aristolochia old stem, focus a portion of the surface tissue, the periderm, under the LPO. Then locate the cortex and observe the following: collenchyma, schlerenchyma, and parenchyma (if still present). Move to the vascular tissues and examine the xylem and phloem. Take note of the lateral meristem, as represented by the vascular cambium.

 

IV. Drawings:

 

1. Fig 5.1 longitudinal section of the palay root tip

2. Fig 5.2 x-s of the Ranunculus young root and label parts enumerate in procedure no. 2

3. Fig. 5.3 x-s Aristolochia old stem and label parts enumerated in procedure no. 3

 

 

 

 

 

V. Questions:

 

1. In a tabulated form, differentiate the following based on cell structure and function:

 

a. parenchyma                       c. schlerenchyma                  e. epidermis

b. collenchyma                       d. endodermis                       f. periderm

2. As to cell components, differentiate between xylem and phloem.

3. List down at least three examples of fruits and vegetables and specify the parts the parenchyma, collenchyma, and schlerenchyma tissues can be identified.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Report Sheet No. 5

Primary Tissues

 

Name: _______________________________ Date Perfomed: ______________

Time: ________________                                     Rating: ____________________

 

 

 

 

Fig. 5.1 Palay root tip, l.s.

 

Fig. 5.2 Ranunculus, young root c.s.

 

 

 

Fig. 5.3 Aristorlochia, old stem, c.s.

 

 

 

 

Answers to questions:

 

1. Table 5.1. Differences of Fundamental Plant Tissues

 

Tissues

Cell Structure

Funtion

Parenchyma

 

 

Schlerenchyma

 

 

Endodermis

 

 

Epidermis

 

 

Periderm

 

 

 

2. List down at least three examples of fruits and vegetables and specify the parts where they parenchyma, collenchyma, and sclerenchyma tissue can be identified.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

3. As to cell components, differentiate xylem and phloem.

 

________________________________________________________________________________________________________________________________________________________________________________________________

 

 

 

 

 

 

 

 

 

ROOT MORPHOLOGY AND PHYSIOLOGY

 

The root is as continuation of the main axis of the plant and there is no distinct boundary that exists between the root and the stem. Generally, roots grow downward into the soil while the stem grows up and found above the ground. Roots are important because it is through these organs that materials such as water and minerals move from the soil solution to the various parts of the plant body. The root epidermis uncutinized which make the root perform its function of absorption efficiently and the amount of transport out of the roots is influenced by the requirements of root tissues themselves. In other words, roots primarily are responsible for absorption and anchorage. They also perform secondary functions as well as storage, support, vegetative propagation, and hold soil particles in place to prevent soil erosion.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Activity 6

Root Morphology

 

I. Objectives:

 

To be able to:

 

1. illustrate and identify the diffirent embryonal zones of the root tip

2. distinguished between the young root from the mature dicot root based on internal anatomy and external morphology

3. list differences between a monocot root and a dicot root.

4. identify the specialized functions and structures of roots

 

II. Materials:

 

Compound microscope

Prepared slides of:

Root tip of Oryza sativa, l.s.

Ranunculus, young root, c.s.

Zea mays root, c.s.

Fresh specimens of the following:

Roots of:

1. Cocos nucifera (coconut)

2. Zea mays (corn)

3. Raphanus sp. (labanos)

4. Pandanus tectorius (pandan)

5. Daucus carota (carrot)

6. Ipomea batatas (camote)

7. Pacarrhizus erosus (singkamas)

8. Rhizopora conjugate (bakawan)

9. Asparagus or dahlia

10. Arachis hypogea (peanut) or any other legume

 

III. Procedure

 

A. Root Systems

1. Examine the root system of Raphanus sativus and Zea mays:

2. Note the differences and classify as to type of root system.

3. Draw them (Fig 6.1 and Fig 6.2)

 

B. Root Tip

1. Examine a prepared slide of the longitudinal section of Oryza sativa, under the LPO.

2. Identify the following regions:

Meristematic region, elongation region, maturation region, protoderm, ground meristem, and procambium

3. Identify also the root cap and the root hair zone

4. Draw and label parts (Fig. 6.3)

 

C. Ranunculus root

1. Examine slides of the cros section of the Ranunculus young and old root, under the LPO

2. Locate and identify the following parts:

a. For young root

epidermis

cortex

endodermis (passage cells, Casparian strip)

stele or central cylinder composed of: pericycle, xylem, phloem, and stellar parenchyma

b. For old root

periderm

cortex

endodermis

pericycle

vascular cambium

primary xylem

secondary xylem

primary phloem

secondary phloem

3. Draw the cross section of the Ranunculus young and old root and label parts accurately (Fig 6.4 and Fig 6.5)

 

D. Zea mays root

1. Examine a prepared slide of the cross section of the Zea mays root, under the LPO.

2. Locate and identify the parts enumerated in the C-2.a

3. Draw the label parts correctly (Fig. 6.6)

 

E. Specialized Parts and Functions

1. Identify the modified structures and the corresponding specialized functions of the roots of the fresh specimens that your group was able to bring.

2. Complete Table 6.2

 

 

 

 

 

 

 

 

 

Report Sheet No. 6

Root Morphology

 

Name: _______________________________ Date Perfomed: ______________

Time: ________________                                     Rating: ____________________

 

Drawings and answers to questions:

 

A. Root Systems

 

 

 

 

Fig 6.1 Raphanus sativus

 

Fig 6.2 Zea mays

 

1. What type of root system is found in:

 

a. monocots?

________________________________________________________________________________________________________________________________________________________________________________________________

 

b. dicots?

________________________________________________________________________________________________________________________________________________________________________________________________

 

2. What root type is adapted in:

 

a. regions with frequently but light rainfall? Why?

________________________________________________________________________________________________________________________________________________________________________________________________

 

b. Regions with frequently but heavy rainfall? Why?

________________________________________________________________________________________________________________________________________________________________________________________________

 

B. Root tip of Oryza sativa

 

 

Fig 6.3 Oryza sativa, root tip

 

1. What is the tissue found at the apex?

________________________________________________________________________________________________________________________________

 

2. Where does this originate?

________________________________________________________________________________________________________________________________________________________________________________________________

 

3. Of what importance is the root cap to the plants?

________________________________________________________________________________________________________________________________________________________________________________________________

 

4. Of how many cells is the root hair composed of?

________________________________________________________________________________________________________________________________________________________________________________________________

 

5. How does the production of root hairs affect the surface area of absorption of roots?

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

6. From what tissue does root hairs arise?

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

C. Ranunculus root

 

 

 

 

Fig. 6.4 young root

 

Fig 6.5 old root

 

1. Is there a cuticle on the epidermis?

________________________________________________________________________________________________________________________________

 

2. How many layers of cells make up the epidermis?

________________________________________________________________________________________________________________________________

 

3. Of what is the cortex made of?

________________________________________________________________________________________________________________________________________________________________________________________________

 

4. Differentiate the passage cells from the Casparian strip.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

5. Differentiate the xylem vessels and tracheids in cross section.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

6. Differentiate the sieve tubes and companion cells in cross section.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

7. How do branch roots arise?

________________________________________________________________________________________________________________________________________________________________________________________________

 

8. Which tissue contains the most starch? Why?

________________________________________________________________________________________________________________________________________________________________________________________________

 

9. How many protoxylem points are present?

________________________________________________________________________________________________________________________________________________________________________________________________

 

D. Zea mays root

 

 

Fig 6.6 Zea mays root