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

Teacher demonstration: Test for the gas evolved.
Discuss observations.
Detailed discussion.
Drawing diagrams.

Gas jar,
Glass funnel,
Water plant,
Beaker.
text book

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

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.
To describe and explain the mechanism of lenticels.

Observe number of stomata of prepared slides of hydrophytes and xerophytes.
Discuss the observations.
Detailed discussion.

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.

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

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.
Gaseous exchange in amphibians.

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.
To explain the mechanism of gaseous exchange in a frog.

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

A gill of a fish.
text book

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

GASEOUS EXCHANGE

Gaseous exchange in mammals.

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.

Discuss at length man?s respiratory system.

Wall chart- Respiratory system in man.

K.L.B. BOOK 2
P. 59

GASEOUS EXCHANGE

The structure of the lungs.
Inhalation.

By the end of the lesson, the learner should be able to:
To explain adaptations of the lungs to their functions.
To describe the process of inhalation in man.

Drawing labeled diagrams coupled with explanations.
Showing movements of ribs during inhalation.
Explain the inhalation mechanism.

Wall charts- Structure of lungs.
Chart / model of a rib cage.

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

GASEOUS EXCHANGE

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 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 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
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.

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
EXCRETION AND HOMEOSTASIS

Diseases of the respiratory system.
Introduction- Definition and importance of homeostasis and excretion.

By the end of the lesson, the learner should be able to:
To state the causes, symptoms and prevention of respiratory diseases.
To define homeostasis and excretion.
To explain necessity of excretion in plants and animals.

Discuss cause, symptoms and prevention of whooping cough TB, bronchitis, etc.
Q/A: Definitions of digestion, ingestion and egestion, secretion and excretion.
Discuss importance of excretion in plants and animals.

Resource person.
text book

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

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.

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.

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.

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

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

EXCRETION AND HOMEOSTASIS

The Liver.
Deamination.
Other functions of the liver.

By the end of the lesson, the learner should be able to:
To draw and label a diagram of the liver.
To explain the function of the liver in deamination.
To state and explain other functions of the liver.

Drawing and labeling diagram of the liver.
Probing questions.
Discussion

Chart-Structure of the liver
text book

K.L.B. BK 2 PP 93-94

EXCRETION AND HOMEOSTASIS

Liver disorders.
Homeostasis.

By the end of the lesson, the learner should be able to:
To name and discuss kidney disorders.
To identify methods of preventing and treating these disorders.
To define the concepts of internal environment and homeostasis.

Exposition and discussion.

text book

K.L.B. BK 2 PP 96-97

EXCRETION AND HOMEOSTASIS

The feedback mechanism.
The hypothalamus.

By the end of the lesson, the learner should be able to:
To differentiate between positive and negative feedback and state their roles in maintaining the desirable point.
To explain the role of hypothalamus in thermoregulation.

Schematic representation of feedbacks.
Exposition and discussion.
Exposition and detailed discussion.

Chart-
Schematic diagram of feedback mechanism
text book

K.L.B. BK 2 PP 97-98

EXCRETION AND HOMEOSTASIS

The skin and thermoregulation.
Blood vessels and their functions in thermo-regulation.
Homeostatic behavioral activities.
Osmoregulation.

By the end of the lesson, the learner should be able to:
To explain the function of the skin in thermoregulation.
To explain the adaptation of blood vessels and their function in thermo-regulation.
To state and explain various homeostatic behavioral activities.
To describe water and salts balance in the body.

Exposition and discussion.
Drawing schematic diagrams.
Discussion on control of body temperature.
Probing questions.
Detailed discussion.

text book
text book,video
text book

K.L.B. BK 2 PP 98
K.L.B. BK 2 PP 99

EXCRETION AND HOMEOSTASIS

Blood sugar.
Diabetes.

By the end of the lesson, the learner should be able to:
To discuss effects of insufficient/ excess sugar in the blood.
To explain regulation of blood sugar.
To distinguish diabetes mellitus from diabetes inspidus.
To identify simple symptoms of diabetes mellitus and diabetes inspidus.

Detailed discussion.
Detailed discussion.
Probing questions.
Topic review.

text book

K.L.B. BK 2 PP 101-102