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Геоэкология на гриф УМО (2).doc
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Questions

  1. What substances are considered air pollutants?

  2. What is the contribution of city transport to environmental pollution in cities?

  3. Compare pollutants emitted by gasoline and diesel engines. Which type of fuel gives more essential environmental impact?

  4. What direct criteria of atmosphere estimation do you know?

  5. What is MPCcc? Name the values of MPCcc for the main pollutants of the atmosphere.

Laboratory work № 2

Investigation of physiological characteristics of organism adaptation to low temperature

Aim: To study the influence of low environmental temperature on physiological processes in an organism and reveal its adaptation capabilities.

Equipment: Plastic basin with cold water, blood-pressure meter, clock, pen, ruler, note-book.

Theoretical introduction

Capacity for adaptation is one of the main properties of living matter on our planet. Any organism is able to live in a definite temperature range. Warm-blooded animals’ outer body layers form a more or less distinct “film”, the temperature of which changes in the wide range. Stable temperature defines only the region of vitally important organs and processes. But superficial tissues can withstand its more marked fluctuations. When decreasing the temperature of medium the metabolism of warm-blooded organisms intensifies, at the same time the compression of the surface blood vessels and expansion of deep ones takes place as an adaptive reaction, which results in conservation of body.

Practical part

Physiologic adaptation characteristics to low temperature can be studied by means of a simple action – to drop hands into the ice water. This experiment allows us to study the adaptation reaction of the organism to the intensive cold stimulation.

To make this research it is necessary to select 3-4 students from the group born and grown in different climatic conditions. Then, measure the first student’s systolic and diastolic pressure, then let him drop his hand into the ice water. In 3 minutes measure his pressure one more time, and let him drop the hand into ice again. In 3 minutes more the tested student should remove his hand from the cold water. It is necessary to measure his pressure one more time. Measure the pressure every 3 minutes until the determined parameters reverts to the original state. Write down all registered data in the course of study. Carry out similar research for the other tested students.

Plot the graphs according to the results obtained, the abscissa being the data of systolic pressure (in mm of mercury), whereas the ordinate is the time in three-minute interval. Compare the graphs obtained, make a conclusion on the research.

According to the theory the students’ systolic pressure can increase by 20-40 mm mercury at cold simulation. In this case people getting used to cold climate the reaction is less distinct in general, but thee arterial pressure values are normalized faster.