AIR POLLUTION BY GREEN HOUSE GASES (CARBON DIOXIDE AND METHANE) CONTRIBUTING TO GLOBAL WARMING.

GLOBAL WARMING
The atmosphere is trapping too much heat and causing the earth to heat up. This is known as GLOBAL WARMING.
GREEN HOUSE GASES
Carbon dioxide , Methane ,Nitrous oxide ,CFCs etc are called ‘green house gases’. These gases form a layer in the atmosphere and this layer acts like glass in the ‘green house’. Most of the light energy from the sun is emitted in short wave lengths, and it can pass through the layer of green house gases. The sun light warms the ground and the warm ground sends out radiation with longer wave lengths which cannot pass out through the layer of Carbon dioxide  .So in effect, Carbon dioxide  lets the light energy in, but doesn’t let all the heat energy out. So heat is trapped in the atmosphere as in a green house.

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EFFECT OF HUMAN ACTIVITY ON ECOSYSTEM

Pollution
Learning Objectives
Describe the effects of man on the ecosystem with emphasis on the examples of international importance (Tropical rain forest, oceans, and important rivers)
Describe the consequences of deforestation in terms of soil stability, climates and local human population.
Evaluate the effects of:
Water pollution by sewage, by inorganic waste and nitrogen containing fertilizers.
Air pollution by Sulphur dioxide and oxides of nitrogen (acid rain)
Pollution due to insecticides.

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SUPPORT, MOVEMENT & LOCOMOTION

elbow joint 4
Support: refers to the skeleton and its role in holding up the body structure and giving shape.
Movement: refers to the change in the position of one part of the body in relation to another part.
Locomotion: refers to the movement of the entire body from one place to another.
Humans and all other vertebrates have skeletons based on the following plan. The skull, backbone (vertebral column) and rib cage form the main axis of the body and so are called axial skeleton. The shoulder blades, hips and the arm and leg bones are attached (appended) to the axial bones and so are called the appendicular skeleton.
The bone contains 50% water and 50% solid matter. The solid matter consists of 57% calcium carbonate and calcium phosphate and 33% organic matter
FUNCTIONS OF BONES

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USE AND ABUSE OF DRUGS

 

Definition:- a drug is an externally administered substance which modifies or affects chemical reactions in the body.

Beneficial effects of drugs

  1. For pain relief – drugs like aspirin, paracetamol and morphine.
  2. For treatment of diseases – diseases caused by bacteria, such as syphilis are treated with drugs called Antibiotics. A well-known antibiotic is penicillin.
  3.  For its mood influencing effect. – Useful for treating patients with emotional disorders such as depression.
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