Answer the following brain teasers
1. What causes convection current on earth?
2.How do trees help in the formation and protection of soil?
3.What is double circulation?
4. Why the seeds does require the protective coat?
Answers
Explanation:
The answers for the following brain teasers:
1) Convection currents are the result of differential heating. Lighter (less dense), warm material rises while heavier (more dense) cool material sinks. It is this movement that creates circulation patterns known as convection currents in the atmosphere, in water, and in the mantle of Earth.
2) Roots help stabilize the soil and keep it from being blown or washed away. In addition, the leaves and branches of the tree adds organic material to the soil. The tree also can provide protection for understory growth of other types of plant materials that contribute to soil formation.
3) Double circulation is the flow of blood twice through the body.It has two flows:pulmonary and systemic circulation. Left ventricle pumps this blood to lungs through pulmonary arteries. Now oxygenated blood from lungs enters the heart by Pulmonary veins. Now blood moves towards Right atrium and then to right ventricle.
4) When spores are released they keep floating in the air. Each spore is covered by a hard protective coat to withstand unfavourable conditions such as high temperature and low humidity. So they can survive for a long time. Under favourable conditions, a spore germinates and develops into a new individual.
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