Lesson Notes By Weeks and Term - Junior Secondary School 1

SUBJECT:  BASIC SCIENCE           

CLASS:  JSS1

DATE:

TERM: 3RD TERM

REFERENCE

• Precious seed BASIC SCIENCE FOR JUNIOR SECONDARY SCHOOLS BOOK 1

WEEK ONE

ENVIRONMENTAL POLLUTION (I)

Pollution occurs when pollutants contaminate the natural surroundings; which brings about changes that affect our normal lifestyles adversely. “Pollution is the introduction of contaminants into the environment that cause harm or discomfort to humans or other living organisms, or that damage the environment” which can come “in the form of chemical substances, or energy such as noise, heat or light”.

Types of pollution

• Water Pollution
• Air Pollution
• Soil Pollution

WATER POLLUTION

“Water Pollution” is the type of pollution that involves the contamination of various water bodies. Various aquatic creatures depend on these water bodies and its natural nutritious features to support its life. Water pollutants include insecticides and herbicides, food processing waste, pollutants from livestock operations, volatile organic compounds (VOCs), heavy metals, chemical waste and others.

EVALUATION

1. What is pollution?
2. Mention three types of pollution.

CAUSES OF WATER POLLUTION

Industrial waste gets dumped into these water bodies. This causes a chemical imbalance in the water leading to death of the aquatic beings.

Insecticides, pesticides and ripening chemicals that are used on plants run into the ground water system or nearby streams.

Washing clothes near lakes and rivers causes detergents also causes a condition called “Eutrophication” which blocks sunlight from entering inside and reduces oxygen values in the water causing an inhabitable environment.

‘Oil Spills’ are caused when giant oil tankers and oil rigs which are present in the oceans are damaged by either natural or human errors cause a long-time damage to the ocean as oil is lighter than water and floats on water forming a layer blocking sunlight.

Certain natural disasters like flash floods and hurricanes cause the intermixing of water with harmful substances on the land.

PREVENTIVE MEASURES

People can take certain preventable measures to stop water pollution like being more cautious of dumping contaminants onto the water. For the repair of the damage that has already been done, water treatment plants are being constructed with innovative techniques to clean the polluted water. But as always a certain part of the damage can be resolved therefore, it is better to prevent water pollution as water is basic need for the survival of man.

EVALUATION

1. State three causes of water pollution.
2. How can water pollution be controlled?

AIR POLLUTION

The contamination of the air present in the atmosphere is known as “Air pollution”. Respiration is an important life process of all living things. We breathe in the air present in the atmosphere. Therefore if the air around us is contaminated with poisonous gases, it would have a fatal effect on us. Some of the most notable air pollutants are sulfur dioxide, nitrogen dioxide, carbon monoxide, ozone, volatile organic compounds (VOCs) and airborne particles.

CONSTITUENTS OF AIR

The air naturally comprises of 78% of nitrogen, 21% of oxygen, 0.9% of oxide gases and 0.1% of inert gases. When this balance is disturbed, it causes disruptions of severe proportions

WHAT CAUSES AIR POLLUTION?

• Partially combusted exhaust gases released from internal combustion engines add poisonous gases into the atmosphere.
• Certain industries release some gases like sulphur dioxide and carbon monoxide which mix with the air and clouds and cause acid rains.
• Burning of discarded plastic, wood and rubber also release carcinogenic gases into the atmosphere.

CONTROL MEASURE

Air pollution is very much fatal to living things as almost all living beings respire directly from the atmosphere without undergoing any treatment like water. Hence use of catalytic converters in vehicles, preventing the burning of used products, leaving vehicles running for lengthy periods of time during halts and such environment friendly actions.

EVALUATION

1. Define air pollution.
2. Mention four causes of air pollution.

SOIL POLLUTION

Stripping soil of its natural fertility by using artificial chemicals like pesticides, insecticides, ripening agents etc. is known as “Soil Pollution”. Plants depend on the nitrogenous compounds present in the soil for their nutrition. Use of insecticides, pesticides and other artificial chemicals absorbs the nitrogen from the soil making it unfit for the growth for plants. Plants are responsible for holding the soil together firmly so, when the plants can’t grow the soil splits, leading to soil erosion. Some soil pollutants are: hydrocarbons, solvents and heavy metals.

GENERAL EVALUATION

1. Define air pollution.
2. Mention four causes of air pollution.
3. State three causes of water pollution.
4. How can water pollution be controlled.
5. Mention the types of pollution.

READING ASSIGNMENT

Precious seed BASIC SCIENCE FOR JUNIOR SECONDARY SCHOOLS BOOK 1 PAGE 41-57.

WEEKEND ASSIGNMENT

1. Stripping soil of its natural fertility by using artificial chemicals like pesticides, insecticides, ripening agents etc. is known as A. Soil Pollution B. land pollution 

1. thermal pollution D. water pollution.

1. Plants are responsible for holding the soil together firmly so, when the plants can’t grow the soil splits, leading to ____ A.  soil erosion B. sedimentation C. soil split 

1. none.

1. VOCs means ____ A. volatile organic compounds B. voice of country C. voicing of centralized D. none.
2. Washing clothes near lakes and rivers causes detergents and also causes a condition called  A. Eutrophication B. hydrocarbons C. disruptions of severe proportions D. Oil Spills.
3. ____ occurs when pollutants contaminate the natural surroundings; which brings about changes that affect our normal lifestyles adversely. A. Pollution B. pollutants 

1. farts D. osmosis.                                         

THEORY

1. State three causes of water pollution.
2. List five types of pollutants.