LAB HELP - BREATHING AND RESPIRATION - To demonstrate that yeast respires

 TOPIC: BREATHING AND RESPIRATION 

AIM: To demonstrate that yeast respires

APPARATUS/MATERIALS:

·         2 boiling tubes

·         bung

·         delivery tube

·         glucose solution

·         yeast

POSSIBLE DISCUSSION QUESTIONS:

BACKGROUND

1.       Define respiration

2.       Name the two types of respiration

3.       State that yeast respires both aerobically and anaerobically.

4.       Which type of respiration takes place in this experiment?  How do you know?

5.       Write a word/chemical equation to represent the type of respiration in yeast.

6.       Which enzyme catalyzes respiration in yeast?

7.       What is the standard laboratory test for carbon dioxide? (Equation?)

8.       Which set-up serves as a control?  What is the purpose does the control serve in this experiment?


EXPLANTION OF RESULTS

10.   Compare expected results with experimental results

11.   How would you determine that anaerobic respiration did not take place?

      


PRECAUTIONS/LIMITATIONS/SOURCES OF ERROR

12.   Why is it important to use fresh yeast?

13.   Is it advisable to breathe near the tube containing lime water?

REVISION OUTLINE - RESPIRATION - INTEGRATED SCIENCE

1.    Define Aerobic Respiration

1.1.    word equation 

2.    Define Anaerobic Respiration

2.1.   word equation

2.1.1.   muscle

2.1.2.   yeast

3.    State ( industrial) applications of anaerobic respiration

3.1.   Breadmaking

3.2.   Brewing

3.3.   Yoghurt, cheese, sour cream

3.4.   Etc.

4.    Distinguish between aerobic and anaerobic respiration

4.1.   Site of reaction

4.2.   Oxygen requirement

4.3.    in/complete breakdown of glucose

4.4.   products

4.5.   Amount of energy produced

5.   Describe experiment to show that living things respire

6.    Understand that in plants, products of photosynthesis are substrates of respiration

6.1.   Surplus of oxygen during day

6.2.   Surplus of  carbon dioxide during night

BREATHING

7.    Define Breathing

8.    Distinguish between breathing and respiration

9.    Describe the mechanism of breathing in humans

9.1.   Inspiration/Inhalation

9.2.   Expiration/Exhalation

10. Draw analogy between bell-jar model and human respiratory system ( bell jar, bung, Y-shaped tube,  2 balloons, rubber sheet)

11. Compare composition of inhaled air and exhaled air

11.1. Oxygen

11.2. Carbon dioxide

11.3. Nitrogen ^a

11.4. Noble gases

11.5. Water vapour

11.6. Heat

12. Describe the structure and function of the human respiratory system

12.1. Nose, mouth, trachea, larynx, rings of cartilage, bronchi (left bronchus and right bronchus), bronchioles, alveoli, pleural membrane, pleural fluid, pleural cavity, diaphragm, ribs, internal and external intercostal muscles)

13. Respiratory Problems due environmental pollution

13.1. Asthma

13.2. Bronchitis

13.3. Emphysema

13.4. Lung Cancer

GASEOUS EXCHANGE

14. Define gaseous exchange

15. State the characteristics common to gaseous exchange surfaces

15.1. Large surface area

15.2. Thin surface for rapid diffusion
15.3. Moist surface

15.3. Maintenance of concentration gradients 

16. Describe gaseous exchange in the alveoli

16.1. Labelled diagram required

16.2. Adaptations of the alveoli for gaseous exchange

17. Describe breathing mechanism in fish

18. Describe gaseous exchange in gills

18.1. Labelled diagram insightful

18.2. Adaptations of the gills for gaseous exchange

 a.    Some texts show a lower percentage composition of nitrogen in expired air, suggesting that some nitrogen is used. This is not the case.  The actual nitrogen content remains the same. However, since extra water vapour in expired air adds volume to total expired air, then the percentage composition of nitrogen works out to be less.