Experiments and Activities You Need To Know How To Describe

The Nature and Variety of Living Organisms

Structures and Functions in Living Organisms

1. Preparation of plant and animal cells (onion and cheek cells for microscope observation)
2. Osmosis in a model cell (Visking tubing – mass)
3. Osmosis in potato cells (potatoes – length)
4. Factors affecting the activity of catalase (raw/boiled/ground liver and hydrogen peroxide – height of froth)
5. What temperature does amylase work best at? (starch suspension, water baths – color of iodine solution)
6. Test for glucose (mixture of food extract and Benedict’s solution in boiling tube in hot water  bath – blue -> yellow/red)
7. Test for starch
8. Measuring the energy values of foods (holding burning food under a boiling tube of water until food is fully burnt – temperature change)

(f) Respiration

1. Respiration in animals and plants (breathing into a tube entering limewater)

(Experiments like this and variations)

(g) Gas exchange in humans

1. Effect of exercise on breathing rate http://www.curriculumonline.ie/en/Post-Primary_Curriculum/Senior_Cycle_Curriculum/Leaving_Certificate_Established/Biology/Biology_Support_Materials/Prescribed_Activities/Detailed_Templates/Investigate_the_effect_of_exercise_on_the_breathing_rate_or_pulse_rate_of_a_human.html

Transport in plants

1. Role of environmental factors in determining the rate of transpiration from a leafy shoot

• effect of wind (distance of fan) – photometer setup
• effect of light (distance of lamp – put a layer of perspex in between) – photometer setup
• effect of humidity (different-sized plastic bags around leaves) – photometer setup

 

Experiment to Measure the Speed of Sound in Air

1. Stand a measured distance from a building with a large, flat wall. Try to have no obstacles in the way.
2. As a trial, clap two wooden blocks together. An echo is heard: this is the clapping sound traveling to the wall and reflecting back at you. Clap repeatedly in time with the echoes (clap – echo – clap – echo etc.). Once a constant rhythm is achieved…
3. Have someone begin timing as you clap 51 times, stopping time on the 51st clap.
4. To calculate the speed of sound, divide 2x the distance to the wall by 1/50th the time for the 50 claps (the 51st is not included because that is when the stopwatch stopped timing).

Experiment proving that exhaled air contains more carbon dioxide than inhaled air

(A, B and C refer to the tubes unless specified)

Close end of B. Breathe in. Air from atmosphere enters through A, passes through limewater and enters your mouth (cannot enter through B because closed).

Open end of B and close end of A. Breathe out. Exhaled air passes through limewater in test tube B and exits through B.

Limewater in test tube B (which contained the air you exhaled) turns milky much faster than in test tube A (which contained the air you inhaled).

Photosynthesis Investigations for Chlorophyll, Carbon Dioxide, Light