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.
Stomata and habitats of plants.
Lenticels.

By the end of the lesson, the learner should be able to:
To describe an experiment to show release of O2 by plants.
To describe the structure and explain the functions of stomata.
To describe and explain the mechanism of opening & closing of stomata.
To relate plant habitats and the no. of stomata.
To explain the variation between number of stomata on the upper and lower face.
To describe and explain the mechanism of lenticels.

Teacher demonstration: Test for the gas evolved.
Discuss observations.
Detailed discussion.
Drawing diagrams.
Detailed discussion.
Observe number of stomata of prepared slides of hydrophytes and xerophytes.
Discuss the observations.

Gas jar,
Glass funnel,
Water plant,
Beaker.
text book
text book
Prepared slides of hydrophytes and xerophytes.

K.L.B. BOOK 2
P. 49
K.L.B. BOOK 2
P. 51

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.
Breathing in insects.
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 describe the mechanism of gaseous exchange in insects
To describe the breathing mechanism in an insect.
To give an account of the number, position and shape of spiracles of insects.
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 tracheal system of a grasshopper.
Discuss at length the structure of the tracheal system.
Detailed discussion.

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.
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.

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

A gill of a fish.

K.L.B. BOOK 2
PP. 53, 54
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.
To list down parts of the tracheal system in man.
To describe the function of the parts of a system respiratory.

Q/A: Various methods of gaseous exchange in a frog.
Discuss gaseous exchange through the mouth, lungs and skin of a frog.
Discuss at length man?s respiratory system.

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 the process of exhalation in man.
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.

Showing movements of ribs during inhalation.
Explain the inhalation mechanism.
Showing movements of ribs during exhalation.
Explain the exhalation mechanism.
Teacher presents a model thoracic cavity.
Q/A: Comparing parts of the model cavity and the actual rib cage.
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
PP. 61-63

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.

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
GASEOUS EXCHANGE
RESPIRATION

Inhaled and exhaled air.
Diseases of the respiratory system.
Introduction ? Definition and importance of respiration.

By the end of the lesson, the learner should be able to:
To test for CO2 in the air we inhale/ exhale.
To state the causes, symptoms and prevention of respiratory diseases.
By the end of the lesson, the learner should be able:
To define respiration.
To explain significance of respiration.

Observe colour changes of lime water, and make deductions.
Brief discussion.
Discuss cause, symptoms and prevention of whooping cough TB, bronchitis, etc.
Q/A: Definition
Brief discussion of significance of respiration.

Lime water.
Resource person.
text book

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

RESPIRATION

Burning food.
The mitochondrion.

By the end of the lesson, the learner should be able to:
To describe an experiment investigating the gas given off when food is burnt.
To state functions of mitochondrion in respiration.

Teacher demonstration: Burning a food sample.
Testing for the gas evolved during combustion.
Drawing structure of the mitochondrion.
Explain function of the mitochondrion.

text book
Wall charts- The mitochond-rion

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

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.
To describe anaerobic respiration.

Detailed discussion.
Writing down equations of food breakdown.
Observe set up experiments.
Detailed discussion punctuated with probing questions:

text book
Glucose
Yeast
Thermometer

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

RESPIRATION

Oxygen ?debt?.
Applications of anaerobic respiration.
Respiratory substrates & respiratory quotient.

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.
To identify respiratory substrates in the body.
To define respiratory quotient.
To calculate R.Q.

Probing questions.

Detailed discussion.
Q/A: Products of fermentation process.
Listing down various applications of anaerobic respiration.
Brief discussion/ explanations.
Exposition of definition and its significance.
Problem solving.

text book

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

RESPIRATION
EXCRETION AND HOMEOSTASIS

Rate of respiration.
Introduction- Definition and importance of homeostasis and excretion.

By the end of the lesson, the learner should be able to:
To state and explain factors affecting rate of respiration.
To define homeostasis and excretion.
To explain necessity of excretion in plants and animals.

Detailed discussion and explanations.
Q/A: Definitions of digestion, ingestion and egestion, secretion and excretion.
Discuss importance of excretion in plants and animals.

text book

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

EXCRETION AND HOMEOSTASIS

Excretion in plants.

By the end of the lesson, the learner should be able to:
To name plants excretory products.
To state uses of excretory products of plants.

Probing questions.
Exposition of new terms.
Discuss uses and abuses of plant excretory products.

Some plants excretory products.

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

EXCRETION AND HOMEOSTASIS

Excretion and homeostasis in unicellular organisms.
Excretion and homeostasis in animals.
The mammalian skin.

By the end of the lesson, the learner should be able to:
Describe excretion and homeostasis in an amoeba and a paramecium.
To identify excretory organs in various animals.
Draw and label the structure of the mammalian skin.
To describe functions of parts of the mammalian skin.

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

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

text book
Specimens of platyhelmin-thes, annelida, insects.
Permanent slides of mammalian skin.

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

EXCRETION AND HOMEOSTASIS

The lungs.

By the end of the lesson, the learner should be able to:
To explain the role of lungs as excretory organs.

Exposition and discussion.

Chart/ model- Mammalian lungs.

K.L.B. BK 2
P. 87

EXCRETION AND HOMEOSTASIS

The kidneys structure.

By the end of the lesson, the learner should be able to:
To describe the external structure of kidney.
To describe the internal structure of the kidney.

Observe external features of a kidney.
Observe internal drawing and labeling of the kidney.

Wall-Charts?internal organs of a kidney.

K.L.B. BK 2
PP. 89-90

EXCRETION AND HOMEOSTASIS

The nephron.
Urine formation.
The loop of Henle.
Kidney diseases and disorders.

By the end of the lesson, the learner should be able to:
Describe features of the nephron.
To explain formation of urine.
To explain the function of the loop of Henle; and how it?s adapted to its function.
To discuss the role of ADH in determination of concentration of urine.
To name kidney diseases and disorders and state methods of prevention and / treatment.

Discuss features of the nephron.
Draw structure of the nephron.
Label the diagram.
Detailed discussion.
Discussion and explanations.
Probing questions.

Chart?Kidney nephron.
chart
Chart-
The nephron.
text book

K.L.B. BK 2 PP 91-92