GASEOUS EXCHANGE

Introduction. Gaseous exchange in plants.

By the end of the lesson, the learner should be able to:


To explain importance of gaseous exchange.

To describe gaseous exchange in plants.

Discussion
Explanations

Q/A: Products of respiration.
Detailed discussion.

text book

K.L.B. BOOK 2
P. 48

GASEOUS EXCHANGE

Release of CO2 by plants.

By the end of the lesson, the learner should be able to:
To describe an experiment to show release of CO2 by plants.

Class experiments including control experiments.

Explain the observations made.

Bicarbonate indicator, boiling tubes, Aluminum foil.

K.L.B. BOOK 2
P. 49

GASEOUS EXCHANGE

Release of O2 by plants.

By the end of the lesson, the learner should be able to:
To describe an experiment to show release of O2 by plants.

Teacher demonstration: Test for the gas evolved.
Discuss observations.

Gas jar,
Glass funnel,
Water plant,
Beaker.

K.L.B. BOOK 2
P. 49

GASEOUS EXCHANGE

Stomata.
Opening & closing of stomata.

By the end of the lesson, the learner should be able to:
To describe the structure and explain the functions of stomata.

To describe and explain the mechanism of opening & closing of stomata.

Detailed discussion.
Drawing diagrams.

text book

K.L.B. BOOK 2
P. 51

GASEOUS EXCHANGE

Stomata and habitats of plants.

By the end of the lesson, the learner should be able to:
To relate plant habitats and the no. of stomata.
To explain the variation between number of stomata on the upper and lower face.

Observe number of stomata of prepared slides of hydrophytes and xerophytes.

Discuss the observations.

Prepared slides of hydrophytes and xerophytes.

K.L.B. BOOK 2
P. 51

GASEOUS EXCHANGE

Lenticels.

By the end of the lesson, the learner should be able to:
To describe and explain the mechanism of lenticels.

Detailed discussion.

text book

K.L.B. BOOK 2
P. 52

GASEOUS EXCHANGE

Respiratory surfaces in animals.
Gaseous exchange in protozoa.

By the end of the lesson, the learner should be able to:
To define a respiratory surface.
To state characteristics of respiratory surfaces.
To identify the environment or medium of operation of respiratory surfaces.

To describe the mechanism of gaseous exchange in an amoeba.

Teacher exposes meaning of a respiratory surface.
Discuss at length, giving examples of organisms that have a given respiratory surface.
Q/A: Review diffusion, structure of an amoeba.
Discuss briefly gaseous exchange in and out of amoeba.

text book

K.L.B. BOOK 2
P. 53

GASEOUS EXCHANGE

Gaseous exchange in insects.

By the end of the lesson, the learner should be able to:
To describe the mechanism of gaseous exchange in insects

Drawing tracheal system of a grasshopper.
Discuss at length the structure of the tracheal system.
Detailed discussion.

text book

K.L.B. BOOK 2
PP. 53, 54

GASEOUS EXCHANGE

Gaseous exchange in insects.

By the end of the lesson, the learner should be able to:
To describe the mechanism of gaseous exchange in insects

Drawing tracheal system of a grasshopper.
Discuss at length the structure of the tracheal system.
Detailed discussion.

text book

K.L.B. BOOK 2
PP. 53, 54

GASEOUS EXCHANGE

Breathing in insects.

By the end of the lesson, the learner should be able to:
To describe the breathing mechanism in an insect.

Observe breathing movements of live specimens of grasshoppers, locusts or cockroaches.

Live specimens of insects,
Hand lenses,
Boiling tubes.

K.L.B. BOOK 2
P. 56

GASEOUS EXCHANGE

Breathing in insects.
Number, position and shape of spiracles of insects.

By the end of the lesson, the learner should be able to:
To describe the breathing mechanism in an insect.
To give an account of the number, position and shape of spiracles of insects.

Observe breathing movements of live specimens of grasshoppers, locusts or cockroaches.



Drawing the abdomen and showing the position and shape of spiracles, and giving reasons thereof.

Live specimens of insects,
Hand lenses,
Boiling tubes.
Live specimens of insects.

K.L.B. BOOK 2
P. 56

GASEOUS EXCHANGE

Gaseous exchange in a bony fish.

By the end of the lesson, the learner should be able to:
To describe the structure of gills of a bony fish.
To explain how a gill is adapted to function as a respiratory surface.
To explain the mechanism of gaseous exchange in gills.

Drawing and labeling a gill of a fish; stating the function of each part; and stating how it is adapted to its functions.
Detailed discussion.

A gill of a fish.

K.L.B. BOOK 2
PP. 56-57

GASEOUS EXCHANGE

Gaseous exchange in amphibians.

By the end of the lesson, the learner should be able to:
To explain the mechanism of gaseous exchange in a frog.

Q/A: Various methods of gaseous exchange in a frog.
Discuss gaseous exchange through the mouth, lungs and skin of a frog.

text book

K.L.B. BOOK 2
P. 58

GASEOUS EXCHANGE

Gaseous exchange in mammals.
The structure of the lungs.

By the end of the lesson, the learner should be able to:
To list down parts of the tracheal system in man.
To describe the function of the parts of a system respiratory.


To explain adaptations of the lungs to their functions.

Discuss at length man?s respiratory system.
Drawing labeled diagrams coupled with explanations.

Wall chart- Respiratory system in man.
Wall charts- Structure of lungs.

K.L.B. BOOK 2
P. 59
K.L.B. BOOK 2
P. 60-1

GASEOUS EXCHANGE

Inhalation.

By the end of the lesson, the learner should be able to:
To describe the process of inhalation in man.

Showing movements of ribs during inhalation.
Explain the inhalation mechanism.

Chart / model of a rib cage.

K.L.B. BOOK 2
PP. 61-62

GASEOUS EXCHANGE

Exhalation.

By the end of the lesson, the learner should be able to:
To describe the process of exhalation in man.

Showing movements of ribs during exhalation.
Explain the exhalation mechanism.

Chart / model of a rib cage.

K.L.B. BOOK 2
PP. 61-62

GASEOUS EXCHANGE

Thoracic cavity model.
Gaseous exchange in an alveolus.

By the end of the lesson, the learner should be able to:
To identify similarities between a model thoracic cavity and an actual thoracic cavity.
To describe gaseous exchange in an alveolus.
To explain regulation of breathing in man.

Teacher presents a model thoracic cavity.
Q/A: Comparing parts of the model cavity and the actual rib cage.


Discussion and explanations.

Thoracic cavity model.
text book

K.L.B. BOOK 2
PP. 61-63
K.L.B. BOOK 2
P. 64

GASEOUS EXCHANGE

Rate of breathing in man.

By the end of the lesson, the learner should be able to:
To state and explain briefly factors affecting the rate of inhalation / exhalation processes.

Discussion and explanations.

text book

K.L.B. BOOK 2
P. 63

GASEOUS EXCHANGE

Rate of breathing in man.

By the end of the lesson, the learner should be able to:
To state and explain briefly factors affecting the rate of inhalation / exhalation processes.

Discussion and explanations.

text book

K.L.B. BOOK 2
P. 63

GASEOUS EXCHANGE

Intercostal muscles.
Inhaled and exhaled air.

By the end of the lesson, the learner should be able to:
To explain the function of intercostal muscles during the breathing system.

To test for CO2 in the air we inhale/ exhale.

Detailed discussion.
Counting number of inhalations before and after an exercise blow.

Observe colour changes of lime water, and make deductions.
Brief discussion.

Lime water, rib cage model.
Lime water.

K.L.B. BOOK 2
P. 66
K.L.B. BOOK 2
P. 67

GASEOUS EXCHANGE

Inhaled and exhaled air.

By the end of the lesson, the learner should be able to:
To test for CO2 in the air we inhale/ exhale.

Observe colour changes of lime water, and make deductions.
Brief discussion.

Lime water.

K.L.B. BOOK 2
P. 67

GASEOUS EXCHANGE

Diseases of the respiratory system.

By the end of the lesson, the learner should be able to:
To state the causes, symptoms and prevention of respiratory diseases.

Discuss cause, symptoms and prevention of whooping cough TB, bronchitis, etc.

Resource person.

K.L.B. BOOK 2
PP. 67-70

RESPIRATION

Introduction ? Definition and importance of respiration.
Burning food.

By the end of the lesson, the learner should be able to:
By the end of the lesson, the learner should be able:
To define respiration.
To explain significance of respiration.
To describe an experiment investigating the gas given off when food is burnt.

Q/A: Definition

Brief discussion of significance of respiration.
Teacher demonstration: Burning a food sample.
Testing for the gas evolved during combustion.

text book

K.L.B. BK 2
PP. 73-74

RESPIRATION

The mitochondrion.

By the end of the lesson, the learner should be able to:
To state functions of mitochondrion in respiration.

Drawing structure of the mitochondrion.
Explain function of the mitochondrion.

Wall charts- The mitochond-rion

K.L.B. BK 2
P. 74

RESPIRATION

Aerobic respiration.
Anaerobic respiration.

By the end of the lesson, the learner should be able to:
To explain phases of aerobic respiration.
To state difference between aerobic and anaerobic respiration.

Detailed discussion.
Writing down equations of food breakdown.

text book
Glucose
Yeast
Thermometer

K.L.B. BK 2
PP.74-76

RESPIRATION

Oxygen ?debt?.
Applications of anaerobic respiration.

By the end of the lesson, the learner should be able to:
To explain the term ?oxygen debt?.
To explain the effect of ?oxygen debt? on the amount of energy released during respiration.

To explain applications of anaerobic respiration.

Probing questions.

Detailed discussion.
Q/A: Products of fermentation process.
Listing down various applications of anaerobic respiration.

text book

K.L.B. BK 2
P.78
K.L.B. BK 2
P. 79

RESPIRATION

Applications of anaerobic respiration.

By the end of the lesson, the learner should be able to:
To explain applications of anaerobic respiration.

Q/A: Products of fermentation process.
Listing down various applications of anaerobic respiration.

text book

K.L.B. BK 2
P. 79

RESPIRATION

Respiratory substrates & respiratory quotient.

By the end of the lesson, the learner should be able to:
To identify respiratory substrates in the body.
To define respiratory quotient.
To calculate R.Q.

Brief discussion/ explanations.

Exposition of definition and its significance.
Problem solving.

text book

K.L.B. BK 2
P. 79

RESPIRATION

Rate of respiration.

By the end of the lesson, the learner should be able to:
To state and explain factors affecting rate of respiration.

Detailed discussion and explanations.

text book

K.L.B. BK 2
PP. 80-81