Experiment Procedure Summary_0

7/30/2019 Experiment Procedure Summary_0

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Title: To Investigate the Factors Necessary for Germination

Date:

Apparatus: 4 Test tubes; Cotton wool; Cress seeds; Water; Test tube rack; Cool boiled water; Oil; Refrigerator

Method:

1. Place cotton wool in each of four test tubes and label A, B, C and D.

2. Place 10-12 seeds on top of the cotton wool in each of the test tubes.

3. Set up each of the test tubes as follows:

A: Leave the cotton wool dry (without water)

B: Moisten the cotton wool and place the test tube in the refrigerator (without the correct temperature)

C: Cover the seeds and cotton wool with a layer of cool boiled water. Pour a thin layer of oil over the water (without

oxygen)

D: Moisten the cotton wool (water + oxygen + correct temperature)

4. Place test tubes A, C and D in a warm room and leave for 3 4 days.

5. Record which seeds germinated.

Results:

Test Tube Germination

A (without water)

B (without correct temperature)C (without oxygen)

D (control)

Title: To Demonstrate Hypogeal and Epigeal Germination.

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Date:

Apparatus: 2 Large beakers; Soil; 4 Broad bean seeds; 4 Sunflower seeds; Filter paper; Water

Apparatus:

1. Line two large beakers with filter paper.

2. Fill inside the filter paper in each beaker with soil.

3. In one of the beakers, place 4 broad bean seeds between the filter paper and the beaker so that they are visible through

the side of the beaker.

4. In the second beaker place four sunflower seeds between the filter paper and the glass.

5. Water the soil in each beaker and leave the two beakers in a warm room for one week.

6. Observe the seeds throughout the week and note any differences in the germination in the seeds.

Observations:

Title: To Demonstrate Phototropism

Filter Paper

Sunflower Seeds

Beaker + Soil

Broad Bean Seeds

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Date:

Apparatus: Divided box; 3 Petri dishes; Cotton Wool; Cress seeds; Water

Method:

1. Label three petri dishes A, B and C.

2. Into each dish place some moist cotton wool.

3. Add 10-15 cress seeds to each petri dish.

4. Place petri dish A into the first compartment of the box with a window at the side.

5. Place petri dish B into the second compartment of the box with a window on the top.

6. Place petri dish C in to the third compartment of the box with no windows.

7. Leave the box in a warm room for 5-7 days.

8. Observe and record the results.

Observations:

Title: To Demonstrate Geotropism (Clinostat)

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4/35

Date:

Apparatus: Clinostat; 4 soaked broad bean seeds with straight radicles; pins; cotton wool.

Method:

1. Place a pad of moist cotton wool on the cork disc of the clinostat.

2. Pin the four soaked bean seeds onto the disc.

3. Switch on the motor of the clinostat and leave the clinostat in the dark for 2-3 days.

4. Record the observations.

5. The experiment should be repeated without rotating the disc.

6. The results of both experiments should be compared.

Observations and Results:

Title: To Show that Oxygen is Released During Photosynthesis

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Date:

Apparatus: Elodea (pond weed); Pond Water; Funnel; Test tube; Plasticine; Beaker; Lamp; Sodium bicarbonate

Method:

1. Fill the beaker with pond water and place some pond weed in the bottom of the beaker.

2. Place an inverted funnel over the pond weed and secure it in place with some Plasticine.

3. Place a test tube over the funnel as shown in the diagram, making sure that the funnel and test tube are completely filled

with water.

4. Add some sodium bicarbonate to the water this will release carbon dioxide into the water.

5. Place the lamp close to the beaker and switch it on and leave the apparatus for 3-4 days.

6. When all of the water has been pushed out of the test tube, test the gas collected using a glowing splint.

7. If the glowing splint re-lights, the gas present is oxygen.

Results:

Title: To Test a Leaf for Starch

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Date:

Apparatus: Leaf; Boiling water bath; Beaker; Warm water bath; Warm Alcohol; White tile; Iodine; Dropper; Forceps

Method:

1. Remove a leaf from a plant.

2. Place the leaf in the boiling water bath for several minutes this kills the leaf.

3. Remove the leaf from the boiling water bath and place it in a beaker of warm alcohol this removes the alcohol (the leaf

appears a creamy white colour when removed, but is also very brittle)

4. Remove the leaf from the warm alcohol and place into a warm water bath this softens the leaf.

5. Remove the leaf from the warm water bath and place it on a white tile.

6. Using a dropper, add 2-3 drops of iodine to the leaf and observe any colour changes that occur.

Note: Iodine is a brown/orange colour that will turn blue-black in the presence of starch.

Results:

Title: To show that Light is Necessary for Photosynthesis

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Date:

Apparatus: Variegated pot plant; Leaf; Boiling water bath; Beaker; Warm water bath; Warm Alcohol; White tile; Iodine;

Dropper; Forceps

Method:

1. De-starch a potted plant by placing it in the dark for 48 hours.

2. Place the plant close to the lamp and switch on the lamp.

3. Leave the plant to photosynthesise for up to six hours.

4. Remove some of the leaves from the plant and test for the presence of starch.

5. Draw a diagram of the leaves showing the areas containing starch.

Results:

Title: To Demonstrate Osmosis (Visking Tubing)

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Date:

Apparatus: 80% Sucrose solution; Distilled water; Visking tubing; Large Beaker

Method:

1. Soak a length of visking tubing until it is soft.

2. Tie a knot in one end of the visking tubing.

3. Half fill the visking tubing with the 80% sucrose solution.

4. Tie a knot at the other end of the visking tubing.

5. Rinse the outside of the sealed visking tubing with distilled water, dry it and weigh it.

6. Record the initial mass of the visking tubing.

7. Immerse the visking tubing in a large beaker of distilled water and leave for 24 hours.

8. After 24 hours, remove the visking tubing from the beaker and record any observations.

9. Dry the visking tubing and reweigh.

10. Record the final mass of the visking tubing.

Observations:

Results:

Initial Mass - _________g

Final Mass - _________g

Change in Mass - _________g

Title: To Demonstrate Osmosis (Potato)

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Date:

Apparatus: Potato; Knife; Salt; Petri dish; Water

Method:

1. Cut a potato in half.

2. Place the cut end facing downwards in a petri dish of water.

3. Scoop out a hollow in the top of the potato.

4. Fill the hollow with salt.

5. Leave the potato for 24 hours and record any changes.

Results:

Title: To Show the Action of a Semi-Permeable Membrane

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Salt


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Date:

Apparatus: Visking Tubing; Starch Solution; Iodine; Water; Large Beaker

Method:

1. Soften a length of visking tubing by placing it in distilled water.

2. Tie a knot at one end of the visking tubing.

3. Half fill the visking tubing with the starch solution.

4. Tie a knot at the other end of the visking tubing.

5. Immerse the visking tubing into a beaker of distilled water and iodine.

6. Leave the visking tubing for up to an hour.

7. Observe and record any changes.

Results:

Title: To Show Transpiration in Plants

Water +

Iodine

Beaker

Visking

Tubing

StarchSolution

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12/35

Date:

Apparatus: Potometer; Cutting taken from a herbaceous stem; Water; Vaseline;

Method:

1. Take a cutting from a leafy herbaceous stem.

2. Holding the stem under water (prevents air from getting into the xylem), cut the stem at an angle (exposes a greater area

of xylem).

3. Insert the cutting into the rubber stopper of the potometer and seal with Vaseline (this prevents air from getting into the

system).

4. Remove the potometer from the water and leave for an hour.

5. After an hour, place the end of the potometer tube into a beaker of water this will trap and air bubble in the potometer.

6. Record the position of the air bubble.

7. Place the potometer beside an open window for up to 6 hours.

8. Record the position of the air bubble.

9. Repeat the procedure by placing the potometer in different conditions (humidity; temperature; wind levels etc)

10. The control used is an atmometer this has the same basic structure as the potometer, but instead of a cutting, it

contains a porous pot.

Results:

Title: Test for Starch

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Date:

Apparatus: 2 Test tubes; Test tube rack; Dropper; Water; Starch solution; Iodine.

Method:

1. Label two test tubes A and B.

2. Into tube A, place 2ml of the starch solution.

3. Into tube B, place 2ml of water.

4. Add 2-3 drops of iodine into each test tube and swirl.

5. Note and record any colour changes that occur.

Results:

Solution Initial Colour Final Colour

A Starch Solution

B Water (Control)

Title: To Test for Reducing Sugar

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Date:

Apparatus: Water bath (80O- 100OC); Glucose solution; Water; 2 Test tubes; Dropper; Benedicts solution; Test tube rack;

Test tube holder.

Method:


2. Into tube A, place 2ml of glucose solution.


4. Using a dropper, add 2ml of Benedicts solution to each test tube and swirl.

5. Place both test tubes in the water bath and heat for 5 minutes.6. Remove the test tubes from the water bath and record any colour changes.

Results:


A Glucose Solution

B Water

Title: Test for Protein

Date:

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Apparatus: 2 Test tubes; Water; Protein solution; Biuret reagent; Dropper; Test tube rack

Method:


2. Into tube A, place 2ml of protein solution.


4. Using a dropper, add 2ml of Biuret reagent to each test tube and swirl.

5. Note and record any colour changes.

Results:


A Protein Solution

B Water

Title: Test for Fat

Date:

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ProteinSolution


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Apparatus: Two pieces of brown paper; Source of fat (olive oil); Water; Dropper

Method:

1. Place 2-3 drops of oil on one piece of paper and label it oil.

2. Place 2-3 drops of water on the other piece of paper and label it water.

3. Leave both pieces of paper aside to dry.

4. Hold the pieces of paper up to the light and record the results.

Results:

Sample Translucent Spot

Before Drying After Drying

Oil

Water

Title:To Assess the Dry Matter (DM) of Silage (Squeeze Method)

Date:

Apparatus: Sample of Silage

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Method:

1. Pick up a handful of silage.

2. Squeeze the silage gently between your hands.

3. Squeeze the silage harder between the hands.

4. Note the water released and determine the DM based on the table below.

5. Record results.

When Squeezed Gently If water pours out Low DM

If water only drips out High DM

When Squeezed Hard If water continues to drip out High DM

If water fails to drip out Very high DM

Results:

Title: To Assess the Quality of Silage (Texture, Smell, Colour)

Date:

Apparatus: Sample of Silage

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Method:

1. Pick up a sample of silage.

2. Note the colour of the silage.

3. Pass the silage between your fingers and note the texture of the silage.

4. Waft the sample in front of your nose to note its smell.

5. Good quality silage is characterised by: yellow/green colour; firm texture; sharp sweet smell.

Results:

Title: To Assess the pH of Silage

Date:

Apparatus: Sample of silage; Funnel; Filter paper; Beaker; Conical flask; Universal indicator; Dropper.

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Method:

1. Pick up a sample of silage and squeeze the moisture out of it into a beaker.

2. Filter the silage solution into a conical flask using a funnel lined with filter paper.

3. Add 2-3 drops of universal indicator to the filtered solution and swirl.

4. Compare the colour of the filtrate with the colour chart.

5. Record the pH of the silage.

Results:

Title: To Determine the % Sugar in Sugar Beet.

Date:

Apparatus: Sample of sugar beet; Mortar and pestle; Refractometer

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Silage

Solution

Funnel + FilterPaper

Clear

Solution


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Method:

1. Crush up some sugar beet in a mortar and pestle.

2. Drain off some of the sap.

3. Place the sap in a cuvette.

4. Measure the sugar content of the sugar beet using a refractometer.

5. Compare the refractometer reading with the measurements in the table below.

Refractometer Reading % Carbohydrate

9 10% 3 4%

Greater than 10% Greater than 4%

Note: The same procedure can be applied to measure the % sugar in any foodstuff.

If measuring the % sugar of grass, the grass should be frozen first - this will help to break the cell walls and membranes to

release the sap.

Title: To Determine the % Total Water in Soil

Date:

Apparatus: Electronic balance; Sample of soil; Evaporating basin; Tongs; Oven

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Method:

1. Obtain a fresh sample of soil.

2. Weigh an empty evaporating basin.

3. Place the sample of soil into the evaporating basin and re-weigh.

4. Calculate the weight of the fresh soil.

5. Place the evaporating basin in the oven at 100OC.

6. Leave the soil to dry in the oven for 24 hours and re-weigh.

7. Re-weigh every 24 hours to a constant weight.8. Calculate the % water in the soil.

Results:

Mass of Evaporating Basin = _________________g

Mass of Fresh Soil + Evaporating Basin = _________________g

Mass of Fresh Soil = _________________g

Mass after drying 1 = _________________g

Mass after drying 2 = _________________gMass after drying 3 = _________________g


Mass of Dry Soil = _________________g

Mass of Water = _________________g

% Water = Mass of Water x 100 = _________________%

Mass of Fresh Soil

Title: To Determine the % Available Water in Soil

Date:

Apparatus: Sample of Soil; Evaporating basin; Electronic balance

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Method:

1. Obtain a fresh sample of soil.



4. Calculate the weight of the fresh soil.

5. Leave the dish at room temperature for 24 hours and re-weigh.

6. Re-weigh every 24 hours to a constant weight.

7. Calculate the % available water in the soil.

Results:


Mass of Fresh Soil + Evaporating Basin = _________________g

Mass of Fresh Soil = _________________g





Mass of Dry Soil = _________________g

Mass of Water = _________________g

% Available Water = Mass of Water x 100 = _________________%

Mass of Fresh Soil

Title: To Determine the % Humus (Organic Matter) in Soil

Date:

Apparatus: Sample of dry soil; Evaporating basin; Electronic balance; Bunsen burner; Tripod stand; Tongs; Wire gauze.

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Method:

1. Obtain a sample of dry soil (place soil in an oven at 100O C for 48 hours)



4. Calculate the weight of the dry soil.

5. Place the evaporating basin on a wire gauze on a tripod over a bunsen flame.

6. Heat the sample of soil strongly.

7. Note the smoke and smell.

8. After five minutes, cool the sample and reweigh.

9. Continue heating in 5 minute intervals and re-weighing to a constant weight.

10. Calculate the % humus in the soil.

Results:


Mass of Dry Soil + Evaporating Basin = _________________g

Mass of Dry Soil = _________________g





Mass of Dry Soil - Humus = _________________g

Mass of Humus = _________________g

% Humus = Mass of Humus x 100 = _________________%

Mass of Dry Soil

Title: To Determine the Composition if Soil

Date:

Apparatus: Sample of soil; 250ml Graduated cylinder; Water; Stopper.

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Method

1. Collect a sample of soil.

2. Place 50cm3 of the soil into the graduated cylinder.

3. fill the cylinder with water, stopper the cylinder and shake well.

4. Allow the soil to settle (sediment) overnight.

5. Examine and measure the volume of sand, silt, clay and humus.

6. Calculate the % of each in the soil sample.

Results:

Volume of Fresh Soil = ______________________ Volume of Mineral Matter = ______________________

Vol of Sand = ___________ % Sand = _____________ Vol of Sand = ___________ % Sand = _____________

Vol of Silt = ____________ % Silt = ______________ Vol of Silt = ____________ % Silt = ______________

Vol of Clay = ____________ % Clay = ____________ Vol of Clay = ____________ % Clay = ____________

Title: To Show Flocculation in a Sample of Clay Soil

Date:

Apparatus: Sample of soil; 2 Test tubes; Lime; Water; Test tube rack

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Method:

1. Label 2 test tubes A and B.

2. Place 10cm3 of soil into the 2 test tubes.

3. Place 2cm3 of lime into tube A.

4. fill each test tube with water.

5. Cover the tubes and shake for 1 minute.

6. Observe both tubes for 3-5 minutes.

7. Note what happens in each tube.

Results:

Title: To Demonstrate Capillarity in Soil

Date:

Apparatus: 2 Glass tubes; Glass wool; Sample of dry sand; Sample of dry clay; Basin of water.

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Method:

1. Plug the bottom of two glass tubes with glass wool.

2. Place 250cm3 of dry sand into one of the tubes.

3. Place 250cm3 of dry clay into the other tube.

4. Stand the tubes into the basin of water.

5. Observe that water will rise up the soil in both of the tubes.

6. Measure the height of the water in both tubes in 5 minute intervals.

7. Record how long it takes for the water to rise 5cm3 up the tube.

Results:

Title: To Measure the % Air in Soil

Date:

Apparatus: Sample of soil; Small beaker; Large beaker; Water; Graduated cylinder

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Method:

1. Obtain a sample of fresh soil.

2. fill the large beaker with water.

3. Mark the level of water on the side of the beaker (A).

3. Place the small beaker in the large beaker of water and allow the small beaker to fill with water.

4. Remove the small beaker once it has filled with water.

5. The level of water in the large beaker will have dropped.

6. Mark the new level of water in the large beaker (B).

7. Empty the water from the small beaker and fill it with soil but do not press down the soil.

8. Replace the small beaker with the soil into the large beaker of water.

9. Gently, stir the soil in the small beaker to remove trapped air.

10. As the air in the small beaker is removed, the pores in the soil will fill up with water from the large beaker.

11. The level of water in the large beaker will drop, this new level should be marked (C).

12. Using a graduated cylinder, add water to the large beaker to bring the level back up to the original level (A), this is equal

to the volume of air in the soil.

13. Measure the volume of the soil the total volume of the small beaker.

14. Calculate the % air in the soil.

Results:

Volume of air = _________________ cm3

Volume of soil = _________________ cm3

% Air = Volume of Air x 100 = ______________ %

Volume of Soil

Title: To Compare the Porosity of a Clay Soil and a Sandy Soil (Drainage)

Date:

Apparatus: 2 Funnels; Glass wool; 2 Retort stands; 2 Graduated cylinders; Electronic balance; Water; Stopwatch.

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Method:

1. Plug the bottom of 2 funnels with glass wool.

2. Label the funnels A and B.

3. Clamp each of the funnels into a retort stand and place a graduated cylinder under each of the funnels.

4. Place 10g of sand in funnel A and 10g of clay into funnel B.

5. Add 50ml of water to both funnels at the same time.

6. Once all of the water has been added, start the stopwatch and record the volume of water drained from the soil every 5

minutes.

7. Note the time it takes to drain 10ml of water from each soil.

Results:

Time Sand Clay

5 minutes

10 minutes15 minutes

20 minutes

Title: To Measure the pH of Soil

Date:

Apparatus: Test tube; Test tube rack; Deionised water; Funnel; Filter paper; Beaker; Glass rod; Universal Indicator

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Method:

1. Sterilise all equipment and surfaces before the experiment by swabbing with disinfectant.

2. Take 2 sterile agar plates and label them A and B.

3. Sterilise an inoculating loop by dipping it in methylated spirits and flaming in a bunsen burner until the loop turns red.

4. Allow the inoculating loop to cool down by holding it just outside the bunsen flame for up to 30 seconds.

5. Dip the inoculating loop into the sample of soil.

6. Open the lid of the petri dish labelled A at a 45O angle.

7. Streak the inoculating loop across the surface of the agar.

8. Replace the lid as quickly as possible.

9. Sterilise the inoculating loop by flaming until it is red.

10. Leave plate B unopened to act as a control.

11. Seal both plates using parafilm.

12. Write your initials and the date on the underside of the petri dish.

13. Turn the petri dish upside-down and incubate in an oven at 30OC for 24 hours.

14. Observe the growth of bacteria and fungus.

15. Draw a diagram of the plates showing the growth of bacterial and fungal colonies.

Results:

Title: To Show the Presence of Micro-organisms in Milk

Date:

Apparatus: 2 Pre-poured agar plates; Disinfectant; Methylated spirits; Bunsen burner; Inoculating loop; Sample of milk;

Incubator or oven; Parafilm.

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Method:

1. Sterilise all equipment and surfaces before the experiment by swabbing with disinfectant.

2. Take 2 sterile agar plates and label them A and B.

3. Sterilise an inoculating loop by dipping it in methylated spirits and flaming in a bunsen burner until the loop turns red.

4. Allow the inoculating loop to cool down by holding it just outside the bunsen flame for up to 30 seconds.

5. Dip the inoculating loop into the sample of milk.

6. Open the lid of the petri dish labelled A at a 45O angle.

7. Streak the inoculating loop across the surface of the agar.

8. Replace the lid as quickly as possible.

9. Sterilise the inoculating loop by flaming until it is red.

10. Leave plate B unopened to act as a control.

11. Seal both plates using parafilm.

12. Write your initials and the date on the underside of the petri dish.

13. Turn the petri dish upside-down and incubate in an oven at 30OC for 24 hours.

14. Observe the growth of bacteria.

15. Draw a diagram of the plates showing the growth of bacterial colonies.

Results:

Title: To Assess the Hygienic Quality of Milk (The Resazurin Test)

Date:

Apparatus: 3 Test tubes; Test tube rack; 10ml Graduated cylinder; Samples of milk fresh unpasteurised, fresh pasteurised,

stale pasteurised; Water bath at 37OC; Resazurin solution; Dropper.

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Milk


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Method:

1. Label three test tubes A, B and C.

2. Place 10ml of fresh unpasteurised milk into tube A.

3. Place 10ml of fresh pasteurised milk into tube B.

4. Place 10ml of stale pasteurised milk into C.

5. Place the three test tubes into the water bath.

6. Into each of the test tubes, add 1ml of Resazurin.

7. Record the initial colour in each tube.

8. Leave the test tubes for 10 minutes and record any colour changes.

Results:

Test tube Initial Colour Final Colour

A Fresh Unpasteurised

B Fresh Pasteurised

C Stale Pasteurised

Title: To Dissect a Sheeps Heart

Date:

Apparatus: Sheeps heart; dissecting board; scalpel, scissors, forceps, pins, seeker, dropper, green food dye.

Water

Bath

Test

Tube

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Method:

1. Place the sheeps heart on the dissecting board.

2. Distinguish between the front and the back of the heart by finding the coronary artery this is running diagonally across

the front of the heart.

3. Locate the major blood vessels attached to the heart and identify them the aorta, pulmonary artery, the vena cava and the

pulmonary vein.

4. Note the location of the fat deposits surrounding the heart.

5. To begin dissecting the heart, make a cut using the scalpel down the left side of the heart through the ventricles. Make the

same type of incision down the right side of the heart.

6. Once the ventricles are opened, notice the thickness of the walls of the ventricles. Locate the tricuspid and bicuspid

valves.

7. Continue using the scalpel to cut through the walls of the atria notice the thickness of the atria walls and compare themto the walls of the ventricles.

8. Identify the semi-lunar valves.

9. Locate the septum separating the left from the right side of the heart. Compare the thickness of the septum with the other

walls of the heart.

10. Locate the opening to the coronary artery found at the base of the aorta. Fill a dropper with green food dye and pump

the dye into the coronary artery to follow the path of blood flow through the vessel.

11. Make a labelled diagram of the dissected heart.

Title: To Determine the Eating Quality of Ware Potatoes

Date:

Apparatus: Different varieties of potatoes e.g. golden wonder, records, British queens, roosters etc., Beaker, electronic

balance, oven.

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Method:

1. Wash all potatoes and dry thoroughly.

2. Weigh three beakers and record the weights. Label the beakers Golden Wonder A, B and C.

3. Repeat step two for Roosters and British queens.

4. Cut the Golden wonders into cubes and fill each of the three labelled beakers. Weigh the beakers with the potatoes and

then calculate the weight of the fresh potatoes.

5. Repeat step four with the Roosters and British queens.

6. Place each of the beakers in an oven at 100OC and dry to a constant weight.

7. Allow the potatoes to cool in the oven and weigh again as soon as the beakers are cool enough to handle.

8. Calculate the mass of the dry potatoes.

9. Calculate the % Dry Matter (% DM) of each of the varieties of potatoes using the formula:

% Dry Matter = Weight of Dry Potatoes x 100

Weight of Fresh Potatoes

Results:

Mass of Empty Beaker: ______________________________________g

Mass of Fresh Potatoes + Beaker ______________________________________g

Mass of Fresh Potatoes ______________________________________gMass of Cool Dry Potatoes + Beaker ______________________________________g

Mass of Dry Potatoes ______________________________________g

Title: To Investigate Inherited Characteristics

Date:

Apparatus: Sample of pupils

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Method:

1. Select five genetically inherited characteristics.

2. Carry out a survey of the class to determine the numbers of pupils with each allele.

3. Make a record of the results.

4. Within each characteristic, determine which allele is dominant and which is recessive.

Results:

Characteristic

Tongue Rolling Ability to Roll Tongue Inability to Roll Tongue

Freckles Freckles Present Freckles Absent

Ability to Taste PCT Ability to Taste Inability to Taste

Ear Lobes Ear Lobes Present Ear Lobes Absent

Widows Peak Widows Peak Present Widows Peak Absent

Experiment Procedure Summary_0

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