BIOLOGY 10

Introduction to Biology

Laboratory Manual

Prepared by: KLLabrador

Table of Contents

|Exercise |Title |Page No. |
|1 |Observation and Description |2 |
|2 |Formulation, Testing of Hypothesis, |6 |
| |and Experimental Design | |
|3 |The Use of Models and Controls |9 |
|4 |Plant and Animal Tissues |14 |
|5 |Cellular Respiration |22 |
|6 |Photosynthesis |27 |
|7 |Phylogeny and Systematics: Survey of Plant and Animal Families |30 |
| | | |
|8 |Plant Form and Function | |
|9 |Animal Form and Function | |
| | | |
| | | |

Exercise 1

Observation and Description

• Objectives: a. define observation and description b. explain the characteristics of a good and valid scientific observation and description c. list down observations on some animal behavior d. organize observations into a unified and coherent description e. recognize the manifestations and characteristics of life

Choice Chamber Experiment (The College Board Biology Lab Manual, 2001) (30 min)

1. Prepare a choice chamber. Label the chambers A, B, and C.

Fig. 1.1. Three-chambered choice chamber

2. Obtain 10 ants from the instructor. Observe the ants using a hand lens/dissecting microscope. Make notes on the following: a. general appearance b. movement c. interaction with each other 3. Make a sketch of an ant. 4. In the choice chamber, add sugar crystals in Chamber A and a substance of your choice in Chamber B. Take note of the selected substance/material used. 5. Place the ants in Chamber C. 6. Count how many ants are found on each chamber every 1min. for 20 min. 7. Tabulate the data and make a graph of the number of ants in each chamber over time.

Garden Snail Experiment (Mader, 1998) (30 min)

External Anatomy and Motion

1. Obtain a garden snail from your instructor. Examine the garden snail, taking note of the following: a. general appearance b. movement

2. Gently poke the snail. Take note of its reaction when the stimulus is applied.

3. Draw the specimen and label the following parts: a. foot b. shell

4. Allow a garden snail to crawl in your hands. Describe how it feels.

Behavior

1. Obtain the following substances from your instructor: a. flour b. laundry detergent c. orange juice

2. Observe the reaction of the snail when offered with the abovementioned substances. Snails move away or foam when they are repelled by the substance, and move toward the substance they are attracted to.

3. Tabulate the data recorded: the substance and the reaction of the snail.

Physical Properties (Duka, I.A. and Diaz M. G. Q, 2007) (1 hour) • Objectives: a. define the three types of mixtures and distinguish one from the other based on their physical properties b. list down observations on physical phenomena c. organize observations into a unified and coherent description d. relate the properties of the cell to the physical properties of the mixtures studied

Prepare the following mixtures. Strictly follow the procedure below in stepwise manner. Use the side questions as guide in writing accurate descriptions of the different mixtures.

1. Salt and Water

Place 10 mL distilled water in a test tube. Add table salt little by little and shake vigorously. Describe and identify the resulting mixture.

Continue adding salt crystals more and more until the crystals no longer dissolve. Identify the resulting mixture.

2. Flour and Water

Place 10 mL of distilled water in a test tube. Add one-fourth teaspoon of flour and shake. Describe and identify the resulting mixture.

3. Oil and Water

Obtain two test tubes. In each tube, place 10 mL of distilled water plus 5 drops of oil. Shake and set aside for 2 minutes. Describe and identify the resulting mixtures.

To the first tube, add 1 mL of 0.1 % baking soda or sodium bicarbonate (NaHCO3). To the second test tube, add 1 mL detergent. Shake the tubes well. Describe and identify the resulting mixture in each of the test tubes. Compare the results.

4. Gelatin and Water

Place 10 mL of distilled water in a test tube. Add one-third teaspoon granulated gelatin. Shake and let stand for 2 to 5 minutes. Describe and identify the resulting mixture.

Warm the mixture gently using an alcohol lamp until the gelatin is dissolved. What state is the mixture in? Using a penlight, allow light to pass through the mixture. Finally, place the test tube in a beaker containing ice cold water for 5 minutes. What state is the mixture in? Identify the resulting mixture.

Self-Assessment Questions

A. Choice Chamber

1. Based on your data, did the ants show a preference from one substance over another? If yes, how were they able to determine that the substance present in one chamber is a more preferable choice than the other? If no, explain why.

2. Ants are social insects and thus, they survive by working together as a colony. Communication is a crucial component for such feat to work. How do ants communicate?

B. Garden Snail

3. What was the reaction of the snail when presented with each substance? Why did the snail exhibit such behavior? Consider what it is about each substance that is causing the snail’s response.

C. Physical Properties

4. In the “Salt and Water” portion of the experiment, why is it that the salt crystals no longer dissolve when added excessively to the water?

5. In the “Oil and Water” portion of the experiment, what are the effects of sodium bicarbonate and detergent on the mixture? Which is the emulsifier? Why?

Exercise 2

Formulation, Testing of Hypothesis, and Experimental Design

Lifted from: Duka, I.A. and Diaz M. G. Q. 2007. Biology 1 laboratory manual: An investigative approach. 8th ed. Laguna: UPLB Institute of Biological Sciences. pp. 33-38.

• Objectives: a. define diffusion and demonstrate this process in gases b. cite molecular weight and time as two factors affecting the rate of diffusion c. formulate a hypothesis on the relationship of each of these factors on the rate of diffusion d. conduct an experiment to determine the effects of the two factors on the rate of diffusion e. compute the partial rate and average rate of diffusion f. conclude on the relationships of molecular weight and time on the rate of diffusion

A. Formulation of Hypothesis

Laboratory Work

1. In groups, fasten a one to two feet glass tube horizontally to a ring stand.

2. Using forceps, carefully and simultaneously moisten two cotton balls of the same size, one with hydrochloric acid (HCl), and the other with ammonium hydroxide (NH4OH).

3. Plug one end of the tube with one wet cotton ball and the other end with the other cotton ball. Do this simultaneously.

4. Carefully watch for the white smoke inside the tube to appear and mark its position. Measure the distance (in cm.) from each cotton to the marked position.

5. Consolidate the data of all the groups and tabulate.

B. Testing of the Hypothesis Concerning the Rate of Diffusion

Laboratory Work

1. Obtain per group a petri dish of agar-water gel with three wells.

2. Label the wells as follows: (a) Potassium Permanganate (KMnO4), (b) Potassium Dichromate (K2Cr2O7), and (c) Methylene Blue.

3. Carefully place one drop of the prepared solution of each substance into each well.

4. Immediately cover the petri dish and measure the diameter (in mm.) of the colored area. Record this for zero minute.

5. At a regular three-minute interval for thirty minutes, measure the diameter of the colored area of each substance and record.

6. Tabulate data.

7. Draw the set-ups at zero minute and after thirty minutes.

For data presentation and analysis, please consult:

Duka, I.A. and Diaz M. G. Q. 2007. Biology 1 laboratory manual: An investigative approach. 8th ed. Laguna: UPLB Institute of Biological Sciences.

Self-Assessment Questions

A. Formulation of a Hypothesis

1. Discuss why the white smoke appeared in the glass tube.

2. Which among the two substances diffused faster? Why? Discuss what factor/s affected the rate of diffusion.

B. General

3. What are the other factors that can possibly affect the rate of diffusion? List at least three.

4. Formulate a hypothesis on the effect of one of the factors you enumerated in number 3.

5. Design an experiment to test your hypothesis in number 4.

Exercise 3

The Use of Models

Lifted from: Duka, I.A. and M. G. Q. Diaz. 2007. Biology 1 laboratory manual: An investigative approach. 8th ed. Laguna: UPLB Institute of Biological Sciences. pp. 39-45, 46-54.

I. Investigation of a Property of the Cell Membrane

• Objectives a. define osmosis and other related terms b. compare the three types of media based on osmotic concentration, osmotic potential, and osmotic pressure c. enumerate the criteria of semipermeability in the cell membrane d. test the hypothesis that the cell membrane is semipermeable

Laboratory Work

A. Responses of red blood cells to solutions of different osmotic concentrations

1. Obtain three small vials.

2. Label the vials: a. A: 0.07 M b. 0.15 M c. 0.030 M

3. Add to each vial 10 mL of the corresponding solutions of NaCl.

4. Wash with a cotton ball dipped in alcohol the end of one finger of a volunteer student.

5. After the alcohol had dried, prick the finger with a sterile lancet.

6. Place on each vial 2 to 3 drops. Then, shake each vial gently.

7. Obtain a drop from each of the three vials and prepare a wet mount. Label the slides to ensure that you will not confuse the different solutions.

Note: The solution under the coverslip will slowly become more concentrated as water evaporates. Add more solution to the edge of the coverslip as necessary to prevent a change in the concentration. Also keep the vial tightly closed.

8. Examine closely each slide under the high power objective (HPO) of the microscope.

9. Draw the red blood cells in each solution. Describe the appearance of the cells in each solution.

10. Obtain a prepared slide of a blood smear. Draw normal red blood cells. Give a short description of these red blood cells.

11. Compare the appearance of the RBCs in the first three preparations with the RBCs in the prepared slide.

12. Explain why these cells appear differently.

B. Responses of Hydrilla leaf cells to solutions of different osmotic concentrations

1. Obtain the smallest leaf from the growing tip of Hydrilla. Place it on a clean glass slide.

2. Add one to two drops of 0.01 M NaCl solution and place a coverslip. Note: If necessary, add more salt solution at the edge of the coverslip. This is to prevent the specimen from drying out, so as not to obtain erroneous results.

3. Examine the whole mount of the leaf under the low power objective (LPO).

4. Locate a portion with only a single layer of cells.

5. Observe the cells.

6. Draw a cell under HPO. Give a short description of the normal Hydrilla leaf cell.

7. Add 0.30 M NaCl at one edge of the coverslip.

8. Withdraw the 0.01 M NaCl solution off from the other side with a filter paper placed against the edge of the coverslip. In this way, 0.01 M NaCl can be replaced with the more concentrated solution without lifting the coverslip.

9. Under HPO, focus on one particular cell and observe the particular changes that occurred.

10. Draw the Hydrilla leaf cell in 0.30 M.

11. Describe the changes that occurred in this cell. Give an explanation for these changes.

12. Make a conclusion on the passage and direction of movement of water through the cell membrane of the red blood cells and Hydrilla leaf cells.

II. The Use of Model to Study a Property of the Cell Membrane

• Objectives a. define a model and give examples of scientific models b. enumerate several uses of a model c. describe the limitations of observing and testing semipermeability in actual cells d. identify a model of the cell membrane that would allow for testing the criteria of semipermeability in the cell membrane e. test the semipermeability of the cell membrane model f. relate the responses of actual cells to the data obtained from the cell membrane model

Laboratory Work

A. Saturated Salt and Water

1. Obtain a piece of dialyzing membrane per group.

2. Wet the membrane in distilled water and open it by squeezing the membrane back and forth with your fingertips. Close off one end by doubling back a half-inch portion and tying it securely.

3. Test for any leak by putting distilled water. Rinse off.

Set-up A

1. Fill the sack with saturated sodium chloride (NaCl) solution. The sack should not be too full but somewhat flaccid.

2. Tie off the other end to close the sack.

3. Weigh the dialyzing bag after blot drying by measuring the displacement of water in a graduated cylinder (1 mL = 1 g).

4. Immerse the bag completely in the distilled water.

5. Weigh it every 5 min. for 50 minutes. Make sure to blot it dry before weighing.

6. Record and tabulate all data.

Set-up B

1. Fill the sack with a dialyzing bag containing distilled water.

2. Place this bag in a beaker containing saturated sodium chloride solution.

3. Measure the weight of the bag as in set-up 1.

4. Record and tabulate all data.

B. Macromolecules

1. Prepare a dialyzing bag with distilled water and a pinch of gelatin granules.

2. Immerse the bag in distilled water and measure its weight as in the preceding set-ups.

3. Record the change in weight.

C. Salt and Methylene Blue

1. Obtain another piece of dialyzing membrane and fill it with NaCl – methylene blue solution.

2. Thoroughly rinse another beaker with distilled water.

3. Place a drop of silver nitrate (AgNO3) on the distilled water and check for any cloudiness. Note: Silver nitrate indicates the presence of sodium chloride. If sodium chloride is present, silver nitrate reacts with it and silver chloride (AgCl) is formed, making the water cloudy.

4. If your test for sodium chloride is negative, slowly immerse the dialyzing bag completely in distilled water.

5. Record the time on how long the water became cloudy and bluish.

6. Record and tabulate data.

Self-Assessment Questions

1. The cell membrane is differentially permeable or semipermeable. Discuss what this means.

2. Compare and contrast the conditions of the animal cells and plant cells when subjected to the following: (a) hypertonic solution, (b) isotonic solution, and (c) hypotonic solution. Account for the differences.

3. Some unicellular freshwater organisms have no cell wall yet they are able to survive in their environment, considering that it is hypotonic. How do unicellular organisms lacking a cell wall avoid bursting?

4. What do you think will happen to the weight of the model if it is left in distilled water for several days? What will happen to the concentration of sodium chloride inside the cell relative to the concentration outside the cell?

5. Was the method of using a model in the experiment sufficiently accurate? Can you suggest alternative ways of making more accurate measurements of diffusion across the membrane?

Exercise 4

Plant and Animal Tissues

I. Plant Tissues

Adapted from: Dickey, J. 2003. Laboratory investigations for biology. 2nd edition. USA: The Benjamin/Cummings Publishing and Co. pp. 17.2 – 17.16.

Mader, S. 1998. Biology laboratory manual. 6th edition. USA: The McGraw-Hill Companies, Inc. pp. 323-340, 375-390.

Soligam-Hadsall, A. G., M. F. M. Sangalang, M. T. Joson-Villegas, N. P. Ona-Villa, and A. A. Barrion 2007. A practical guide to introductory biodiversity: Systematic survey of biological diversity. Laguna: UPLB Institute of Biological Sciences. pp. 57-62, 85-90.

• Objectives: a. illustrate, describe, and differentiate the various types of tissues characteristic of vascular plants b. illustrate and describe how tissues are organized in the regions of the plant organ c. recognize variations of each of the different tissues in different organs

Laboratory Work

A. Meristematic Tissue

1. Obtain a slide of the longitudinal section of the root tip of Zea mays.

2. Focus the specimen under the scanner.

3. Draw the specimen. Include a brief description.

B. Dermal Tissue

1. Obtain a leaf of Rhoeo spathacea.

2. Prepare an epidermal tissue wet mount by peeling off a portion of the upper epidermis.

3. Examine the tissue under the HPO.

4. Draw the epidermal cells. Include a brief description on the shape and arrangement of cells.

C. Ground Tissues

a) Parenchyma

1. Obtain a slide of a cross section of the leaf of Ixora sp.

2. Focus it under the microscope and locate the blade – the flattened portion of the leaf.

3. Observe the epidermal cells, a single layer of cells found at the top and bottom surfaces.

4. The middle portion of the leaf is the mesophyll layer, filled with parenchyma tissue.

5. Note the presence of two layers of the mesophyll layer: (a) palisade and (b) spongy mesophyll layer. a. Palisade Mesophyll Layer – located at the upper epidermis; contain chloroplast and are responsible in carrying most of the plant’s photosynthesis. b. Spongy Mesophyll Layer – located near the lower epidermis; have air spaces that facilitate exchange of gases across the plasma membrane.

6. Draw the parenchyma cells accompanied with a brief description.

b) Collenchyma

1. Examine the cross section of the stem of Cucurbita sp. under LPO.

2. Observe the collenchyma cells which form a layer of tissue just below the epidermis.

3. Note the uneven thickening of the cell walls and the presence or absence of the intercellular spaces.

4. Draw the collenchyma tissues accompanied with a brief description.

c) Sclerenchyma

1. Examine the cross section of the stem Helianthus under LPO.

2. Observe the cortex located below the epidermis.

3. Take note of the vascular bundles.

4. Direct your attention to the mass of red stained cells forming a cap on each vascular bundle. These are the sclerenchyma tissues.

5. Draw the sclerenchyma tissue accompanied with a brief description.

D. Vascular Tissue

a) Vascular Bundles

1. Examine a cross section of Zea mays stem under LPO.

2. Note the numerous vascular bundles scattered throughout the stem.

3. Locate one bundle and focus under HPO.

4. Observe for the following: a. xylem – heavily red stained; transport of materials from roots to shoots. b. phloem – lightly blue stained; transport of photosynthates from shoots to roots. i. sieve tubes ii. companion cells c. sclerenchyma sheath – darkly red stained; encloses the vascular bundle

5. Draw the vascular bundle and label the xylem, phloem (including components), and the sclerenchyma sheath. Include a brief description.

Self-Assessment Questions

1. What are the different types of plant tissues? What are the properties and functions of these tissues?

2. Differentiate the various ground tissues based on their properties and function.
II. Animal Tissues

Adapted from: Dickey, J. 2003. Laboratory investigations for biology. 2nd edition. USA: The Benjamin/Cummings Publishing and Co. pp. 12.1-12.17, 13.1-13.9.

Mader, S. 1998. Biology laboratory manual. 6th edition. USA: The McGraw-Hill Companies, Inc. pp. 229-299.

Soligam-Hadsall, A. G., M. F. M. Sangalang, M. T. Joson-Villegas, N. P. Ona-Villa, and A. A. Barrion 2007. A practical guide to introductory biodiversity: Systematic survey of biological diversity. Laguna: UPLB Institute of Biological Sciences. pp. 69-75, 97-108.

• Objectives a. illustrate, describe, and differentiate the different types of animal tissues b. illustrate and describe the organization of different tissues in an animal organ c. identify the tissues that compromise the anatomical plan of animals in cross section

Laboratory Work

A. Epithelial Tissues

1. Examine under LPO a section of the ciliated epithelium.

2. Locate cilia-bearing cells.

3. Draw the cell and label the ciliated epithelial tissue. Indicate the function.

B. Connective Tissues

a) Vascular Tissue

1. Examine a blood smear under LPO.

2. Locate the erythrocytes, leukocytes, and thrombocytes.

3. Draw and label the blood components. Include a brief description of each.

b) CT Proper

1. Examine the slide of an adipose tissue under LPO.

2. Locate the adipose or fat cells.

3. Draw the adipose tissue accompanied with a brief description.

c) Cartilage

1. Obtain a slide containing a hyaline cartilage and focus under HPO.

2. Look for the chondrocytes, cartilage cells located in the cavities (lacuna) of the bluish matrix.

3. Draw and label the chondrocytes. Include a brief description.

d) Bone

1. Examine a cross section of bone under the scanner.

2. Observe the irregular cylindrical units forming the bone. This is the Haversian System.

3. Focus on one Haversian System and switch to HPO.

4. At the center of the system lies the Haversian Canal, through which blood vessels and nerves pass through.

5. Take note of the darkly-stained osteocytes surrounding the Haversian Canal.

6. Draw the bone tissue showing several Haversian Systems. Include a brief description.

C. Muscular Tissue

1. Obtain prepared slide of the following: a. Skeletal Muscle b. Smooth Muscle c. Cardiac Muscle

2. Examine slides under LPO.

3. Draw each specimen and include a brief description of each.

D. Nervous Tissue

1. Examine a nerve cell smear under HPO. Locate the star-shaped cells.

2. Locate the following: a. Soma/Cell Body – central portion of the neuron containing the nucleus b. Dendrites – short and branched processes radiating from the soma; carry impulses towards the cell body c. Axons – longer processes radiating form the soma; transmit impulses away from the cell body

3. Draw and label the soma, dendrites, and axons. Include a brief description.

Self-Assessment Questions

1. What are the four major types of animal tissues? What are the important functions of each?

2. What are the major types of connective tissues? What are the important roles of each in the organization of life?

3. There are three types of muscles. Skeletal, cardiac, and smooth. List down the differences of each type of muscles observed.
Exercise 5

Cellular Respiration
Lifted from: Duka, I.A. and Diaz M. G. Q. 2007. Biology 1 laboratory manual: An investigative approach. 8th ed. Laguna: UPLB Institute of Biological Sciences. pp. 49-54.

• Objectives a. identify means of measuring the rate of cellular respiration b. enumerate factors which can affect cellular respiration c. formulate hypothesis on the effects of these factors on cellular respiration d. test the hypotheses using the respirometer set-up, Durham tube method, and Smith tube method e. conclude on the effects of these factors on cellular respiration

Laboratory Work

A. Oxygen Uptake in Multicellular Organisms

1. Obtain three respirometers (one for each group).

2. Weigh equal amounts of pre-soaked mongo seeds.

3. Prepare 2 pleated filter papers soaked in KOH.

4. Prepare the following set-up: a. Flask 1: KOH-soaked filter paper b. Flask 2: mongo seeds + KOH-soaked filter paper c. Flask 3: mongo seeds

5. Cover flasks and seal with melted paraffin wax.

6. Take note of the initial level of H2O in the respirometer and mark it.

7. Measure the change in the height of the water every 5 min for 30 min.

8. Tabulate all readings.

9. Compute for the final volume in each set-up.

10. Compute for the Respiratory Quotient using the following formula:

RQ = CO2 uptake / O2 uptake

CO2 uptake (vCO2) = final volume of Flask 3 (v3) – O2 uptake (vO2)

O2 uptake (vO2) = final volume of Flask 2 (v2) – final volume of flask 1(v1)

Therefore: RQ = v3 – (v2 – v1) / (v2 – v1)

Note: RQ reflects the kind of substrate used by the organism. If the RQ value is 0.8, this means that the protein was the substrate. If fat was used as the substrate, the RQ will be 0.7.

11. Determine the kind of substrate utilized by the organism based on the calculated RQ value.

B. Cellular Respiration in Yeast

Laboratory Work

a) Durham Tube Method

1. For each group, obtain two test tubes.

2. Prepare the following set-up: a. Tube 1: 4 mL dH2O + 4 mL glucose + 4 mL yeast suspension b. Tube 2: 4 mL glucose + 4 mL 0.2 M MgSO4 + 4 mL yeast suspension

3. Shake the mixture gently.

4. Slide down an inverted Durham tube into each of the test tube. Ensure that no bubbles are trapped in the inverted Durham tube.

5. Measure the height of the area occupied by the gas at the bottom of the inverted Durham tube every three minutes for thirty minutes.

6. Compute for the volume of the CO2 evolved using the formula: V = πr2h

7. Compute for the rate of CO2 production by dividing the final volume of CO2 evolved by time.

8. Tabulate all results.

b) Smith Fermentation Method

1. Obtain 6 Smith fermentation tubes.

2. Pour 20 mL of the following solutions to the respective tubes: a. Tube 1: starch b. Tube 2: lactose c. Tube 3: sucrose d. Tube 4: glucose e. Tube 5: fructose f. Tube 6: dH2O

3. Add 20 mL distilled water and 20 mL yeast suspension to each tube. Make sure no bubbles are trapped at the close end. Note: To remove trapped bubbles, cover the opening with the palm of one hand and tilt the tube horizontally.

4. Plug the openings with cotton balls.

5. Tie the tubes together at their vertical arms to keep it upright.

6. Set aside where they will not be disturbed.

7. Measure the height of the area occupied by the CO2 evolved every 5 min. for 40 min.

8. Compute for the volume of the gas evolved and the rate of CO2 evolution.

9. Tabulate results.

Self-Assessment Questions

1. In the “Durham Tube Method” portion of the laboratory, which test tube showed the higher amount of CO2 evolved? What was in this tube that caused the higher rate of CO2 evolution? How was it able to do so?

2. In the “Smith Fermentation Method”, what tube had the highest amount of CO2 evolved? What substrate was present in this tube? Why is it that this substrate was able to cause a much higher CO2 evolution compared to the others?

3. Compare your RQ value from the (respirometer) experiment to that of the other groups. Is there a difference in the values? What are the possible sources of error that could’ve given different results?

4. In relation to number 3, can you suggest ways to improve the set-ups that will address the sources of errors?

5. Give the significance of the following in the experiment: a. KOH b. plugging Smith tubes with cotton balls c. MgSO4

Exercise 6

Photosynthesis

Lifted from: Duka, I.A. and Diaz M. G. Q. 2007. Biology 1 laboratory manual: An investigative approach. 8th ed. Laguna: UPLB Institute of Biological Sciences. pp. 46-49.

• Objective a. identify means of measuring the rate of photosynthesis b. discuss factors which can affect photosynthesis c. formulate a hypothesis on the effect of each of these factors on photosynthesis d. test the hypothesis using controls and analyze the experimental results

Laboratory Work

A. Carbon Dioxide Uptake

Bromthymol Blue 1. Obtain 250 mL beaker and fill it with 150 mL distilled water.

2. Place an equal volume of bromthymol indicator. Note: Bromthymol blue is an indicator which changes color depending on the amount of CO2 dissolved in the solution.

3. Introduce CO2 in the solution by blowing through a straw until a color change from blue to yellow is observed.

4. Explain why this happens.

Hydrilla sprigs experiment 1. Pour equal amounts of the solution in four large test tubes labeled A to D.

2. Prepare the following set-up: a. TT A: Hydrilla sprigs + carbon paper wrap b. TT B: Hydrilla sprigs c. TT C: carbon paper wrap d. TT D: none Note: Make sure that the sprigs are of the same developmental stage, length, and leaf size.

3. Let the tubes remain under bright sunlight or artificial light for one hour.

4. Unwrap the test tubes afterwards and observe for any color change in the set-ups.

5. Record all observations and interpret results.
B. Starch Production

1. Obtain two mongo seedlings grown at the same time, temperature, soil type, and water conditions, except that one is grown in the dark while the other is left under natural light condition.

2. Observe the differences between the two sets of leaves.

3. Explain why there are differences.

4. Pick four leaves from each seedlings and place into separate beakers.

5. Add 40 mL of 70 % EtOH into each of the beakers.

6. Heat for 3-5 minutes with gentle shaking.

7. Observe what happens to EtOH after heating.

8. Transfer the heated leaves into separate petri dishes.

9. To each leaf, add two drops I2KI solution. Note: In the presence of starch, I2KI solution reacts with it, producing a characteristic black color.

10. Compare the reactions in the two sets of leaves.

11. Record all observations.

Self-Assessment Questions

1. In the Hydrilla sprigs experiment, why is it that the Hydrilla sprigs weren’t placed in all the tubes? What is the purpose of wrapping the test tubes with carbon paper?

2. Was carbon dioxide utilized by the plant kept in the dark? What experimental observation indicated this? What conclusions can be drawn from the experiment?

3. Can the rate of photosynthesis be measured in a different way?

4. In relation to no. 3, make an outline of your suggested experimental design to address your answer.

5. Give the significance of the following in the experiment: a. Bromthymol Blue b. Ethyl Alcohol c. Heating of Ethyl Alcohol d. I2KI

Exercise 7

Phylogeny and Sytematics:
Survey of Plant and Animal Families

Adapted from: Dickey, J. 2003. Laboratory investigations for biology. 2nd edition. USA: The Benjamin/Cummings Publishing and Co. pp. 12.1-12.17, 13.1-13.9.

Mader, S. 1998. Biology laboratory manual. 6th edition. USA: The McGraw-Hill Companies, Inc. pp. 229-299.

Soligam-Hadsall, A. G., M. F. M. Sangalang, M. T. Joson-Villegas, N. P. Ona-Villa, and A. A. Barrion 2007. A practical guide to introductory biodiversity: Systematic survey of biological diversity. Laguna: UPLB Institute of Biological Sciences. pp. 69-75, 97-108.

I. Plant Classification

• Objectives a. distinguish the characteristic features of the major taxa of Kingdom Plantae b. identify, define, and associate with the corresponding organisms, some structure unique to Kingdom Plantae and each major taxonomic divisions c. recognize some representative of each taxonomic division of the Kingdom and some families of Division Magnoliophyta d. identify common flowering plants with the aid of a dichotomous key

Laboratory Work (Field Investigation)

1. Search for a representative plant specimen for each of the given major classifications in the plant kingdom: a. Bryophytes b. Pterdiophytes c. Gymnosperms d. Angiosperms i. Monocot ii. Dicot

2. Observe and list down 5 morphological characteristics, 2 of which are unique to a given specimen.

3. Draw the habit of the chosen specimen. Supply the scientific name and the common name.

4. Construct a dichotomous key showing all representative species based on your observations.

II. Animal Classification

• Objectives a. identify and describe the characteristics of the major animal phyla b. compare the features of this phyla c. classify the given animal taxa according to major groupings d. give examples of members of the major animal phyla e. construct a dichotomous key of the different phyla of the different animals given, according to observable morphological features

Laboratory Work

1. Obtain a representative specimen from each of the major phyla in the Animal Kingdom: a. Porifera – sponge (Scypha sp.) b. Cnidaria – jellyfish (Aurelia sp.) c. Platyhelminthes – flatworm (Schistosoma sp.) d. Nematoda – roundworm (Ascaris sp.) e. Annelida – earthworm (Lumbricus sp.) f. Mollusca – snail (Helix sp.) g. Arthropoda – cockroach (Periplaneta sp.) h. Echinodermata – starfish i. Chordata – frog (Bufo sp.)

2. Observe and list down five characteristics observed on the specimen’s morphology, two of which are unique to a given specimen.

3. Determine the following: j. Phylum k. Genus l. Common Name m. Type of Coelom n. Symmetry: (a) assymetrical, (b) bilateral, (c) radial

4. Construct a dichotomous key showing all representative species based on your observations.

Instructor Notes: Complement lab work with activities found online (activities included here are in pdf forms: Animal Phyla Guide and The Phylum Comparison Challenge)

Exercise 8

Plant Form and Function

Adapted from: Dickey, J. 2003. Laboratory investigations for biology. 2nd edition. USA: The Benjamin/Cummings Publishing and Co. pp. 17.2 – 17.16.

Mader, S. 1998. Biology laboratory manual. 6th edition. USA: The McGraw-Hill Companies, Inc. pp. 323-340, 375-390.

Soligam-Hadsall, A. G., M. F. M. Sangalang, M. T. Joson-Villegas, N. P. Ona-Villa, and C. L. M. Aurin. 2005. A practical guide to introductory biodiversity: Diversity in structure and function of complex organisms. Laguna: UPLB Institute of Biological Sciences. pp. 1-25.

I. The Root System

• Objectives a. enumerate the characteristics features and functions of roots b. define, describe, and identify the external and anatomical parts of roots c. compare and contrast monocot and dicot roots in terms of their morpho-anatomical features d. identify metamorphosed roots and associate each with their specialized functions

Laboratory Work

A. External Morphology of the Root

1. Obtain a grass and an assigned dicot plant. Examine the root system.

2. Determine the type of root system exhibited by the grass and of the dicot plant. Observe the structures arising from the primary root.

3. Draw the two root systems and label the primary and lateral roots.

B. Anatomy of the Root

a) Root Longitudinal Section Examine under the microscope a longitudinal section of the root tip. Locate the following: a. Region of cell differentiation – composed of meristematic tissue near the root cap b. Region of elongation – rows of newly produced cells as they begin to grow larger c. Region of maturation – region where cells are differentiated into particular cell types; area of the root with root hairs d. Root cap – dead cells at the tip of the root; provides protection as the root grows

b) Dicot Root Examine a cross section of the dicot root of Ranunculus sp. Locate, draw, and label the following: a. epidermis – the outermost layer of tissue b. cortex – layer next to the epidermis, composed of several cell layers c. endodermis – found next to the cortex; composed of a single cell layer d. pericycle – lies next to the endodermis and consists of one to two cell layers; site where the branch roots arise e. stele (protostele)– the primary vascular tissues bounded by the pericycle f. xylem g. phloem

c) Monocot Root Examine a cross section of the monocot root of Zea mays. Locate, draw, and label the following: a. epidermis – the outermost layer of tissue b. cortex – layer next to the epidermis, composed of several cell layers c. endodermis – found next to the cortex; composed of a single cell layer d. pericycle – lies next to the endodermis and consists of one to two cell layers; site where the branch roots arise e. stele (protostele)– the primary vascular tissues bounded by the pericycle f. xylem – conducts minerals from the roots to the stem g. phloem – conducts photosynthates from the leaves to other parts of the plant h. pith – centrally located ground tissue that functions for storage

C. Metamorphosed Root

II. The Shoot System: The Stem

• Objectives a. enumerate the characteristic features and functions of plant stems b. define, describe, and identify the external and anatomical parts of the stem, and the various types of stems c. identify modified stems and associate each with their specialized functions d. compare and contrast monocot and dicot stems in terms of their morpho-anatomical features e. compare primary and secondary growth in stems

A. External Morphology of the Stem

B. Anatomy of the Stem

a) Dicot Stem Examine a cross section of the dicot stem. Locate, draw, and label the following: a. epidermis – outer protective layer b. cortex - layer next to the epidermis c. vascular bundle – occurs in a ring pattern; functions for transport of nutrients d. pith – storage of organic nutrients; centrally located

b) Monocot Stem Examine a cross section of the monocot stem. Locate, draw, and label the following: a. epidermis – outer protective layer b. cortex - layer next to the epidermis c. vascular bundle – scattered all throughout; functions for transport of nutrients d. pith – storage of organic nutrients

C. Metamorphosed Stem

III. The Shoot System: The Leaf

A. External Morphology of the Leaf

B. Anatomy of the Leaf

a) Dicot Leaf

b) Monocot Leaf

C. Metamorphosed Leaf

Exercise 9

Animal Form and Function

Toad Dissection

A) External Anatomy: Body regions and directions

B) Internal Anatomy:

Trace the digestive tract

Trace the pathway of O2 and CO2 gases

Trace the flow of blood: heart – lungs – body (anterior and posterior)

Trace the flow of excretory wastes

Determine the major group of bones

Determine the major muscle groups

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B

A

C