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.
Stomata.
Opening & closing of stomata.

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.
text book

K.L.B. BOOK 2
P. 49

GASEOUS EXCHANGE

Stomata and habitats of plants.
Lenticels.

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.
text book

K.L.B. BOOK 2
P. 51

GASEOUS EXCHANGE

Respiratory surfaces in animals.
Gaseous exchange in protozoa.
Gaseous exchange in insects.

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 insects

Teacher exposes meaning of a respiratory surface.
Discuss at length, giving examples of organisms that have a given respiratory surface.
Drawing tracheal system of a grasshopper.
Discuss at length the structure of the tracheal system.
Detailed discussion.

text book

K.L.B. BOOK 2
P. 53
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

Number, position and shape of spiracles of insects.
Gaseous exchange in a bony fish.

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

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

Live specimens of insects.

A gill of a fish.

K.L.B. BOOK 2
P. 56

GASEOUS EXCHANGE

Gaseous exchange in amphibians.
Gaseous exchange in mammals.

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
Wall chart- Respiratory system in man.

K.L.B. BOOK 2
P. 58

GASEOUS EXCHANGE

The structure of the lungs.

By the end of the lesson, the learner should be able to:
To explain adaptations of the lungs to their functions.

Drawing labeled diagrams coupled with explanations.

Wall charts- Structure of lungs.

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

GASEOUS EXCHANGE

Inhalation.
Exhalation.
Thoracic cavity model.
Gaseous exchange in an alveolus.

By the end of the lesson, the learner should be able to:
To describe the process of inhalation in man.
To describe gaseous exchange in an alveolus.
To explain regulation of breathing in man.

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


Discussion and explanations.

Chart / model of a rib cage.
Thoracic cavity model.
text book

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

Intercostal muscles.

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

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

Lime water, rib cage model.

K.L.B. BOOK 2
P. 66

GASEOUS EXCHANGE

Inhaled and exhaled air.
Diseases of the respiratory system.

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.
Resource person.

K.L.B. BOOK 2
P. 67

RESPIRATION

Introduction ? Definition and importance of respiration.
Burning food.
The mitochondrion.
Aerobic respiration.

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 state functions of mitochondrion in respiration.

Q/A: Definition

Brief discussion of significance of respiration.
Drawing structure of the mitochondrion.
Explain function of the mitochondrion.

text book
Wall charts- The mitochond-rion
text book

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

RESPIRATION

Anaerobic respiration.
Oxygen ?debt?.

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

Observe set up experiments.
Detailed discussion punctuated with probing questions:

Glucose
Yeast
Thermometer
text book

K.L.B. BK 2
P.77

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.
Rate of respiration.

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

EXCRETION AND HOMEOSTASIS

Introduction- Definition and importance of homeostasis and excretion.
Excretion in plants.
Excretion and homeostasis in unicellular organisms.

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


To define homeostasis and excretion.
To explain necessity of excretion in plants and animals.
Describe excretion and homeostasis in an amoeba and a paramecium.

Q/A: Definitions of digestion, ingestion and egestion, secretion and excretion.

Discuss importance of excretion in plants and animals.

Q/A: Review diffusion, structure of an amoeba.
Discuss excretion and homeostasis in an amoeba and a paramecium.

text book
Some plants excretory products.

K.L.B. BK 2
PP. 83-84
K.L.B. BK 2
PP. 84-85

EXCRETION AND HOMEOSTASIS

Excretion and homeostasis in animals.

By the end of the lesson, the learner should be able to:
To identify excretory organs in various animals.

Exposition and discussion.
Observe drawings of various animals showing excretory organs.

Specimens of platyhelmin-thes, annelida, insects.

K.L.B. BK 2
P. 85

EXCRETION AND HOMEOSTASIS

The mammalian skin.

By the end of the lesson, the learner should be able to:
Draw and label the structure of the mammalian skin.
To describe functions of parts of the mammalian skin.

Permanent slides of mammalian skin.

K.L.B. BK 2
PP. 86-87