题目内容
Adaptation of Living Things
Certain animals and plants develop characteristics that help them cope with their environments better than others of their kind. This natural biological process is called adaptation. Among the superior characteristics developed through adaptation are those that may help in getting food or shelter, in providing protection, and in producing and protecting the young. That results in the evolution of more and more organisms that are better fitted to their environments.
Each living thing is adapted to its way of life in a general way, but each is adapted especially to its own distinct class. A plant, for example, depends upon its roots to fix itself firmly and to absorb water and inorganic chemicals. It depends upon its green leaves for using the sun's energy to make food from inorganic chemicals. These are general adaptations, common to most plants. In addition, there are special adaptations that only certain kinds of plants have.
Many animals have adaptations that help them escape from their enemies. Some insects are hidden by their body color or shape, and many look like a leaf or a little branch. The coats of deer are colored to mix with the surroundings. Many animals have the ability to remain completely still when an enemy is near.
Organisms have a great variety of ways of adapting. They may adapt in their structure, function, and genetics; in their development and production of the young; and in other respects. An organism may create its own environment, as do warm-blooded mammals, which have the ability to adjust body heat exactly to maintain their ideal temperature despite changing weather. Usually adaptations are an advantage, but sometimes an organism is so well adapted to a particular environment that, if conditions change, it finds it difficult or impossible to readapt to the new conditions.
Some plants and animals develop superior characteristics so that they may
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Which of the following is not directly mentioned in the passage？
Continuing Medical Education
There is increasing recognition of the need for health workers to continue their education throughout their careers. Not only do health workers themselves wish to improve their own skills and competence, but the introduction of new techniques and equipment and the changes taking place in health needs and health care policies necessitate continued training. The phrase "health care" is intended to mean not just curative treatment for the sick but the whole range of provision for promoting health and preventing disease.
In virtually every situation some response to this need has been made, so continuing education does take place -- even though it may in many instances be ineffective or insufficient. Continuing education may be initiated by the health workers themselves, by their supervisors, by the managers of the health system, or by other agencies such as professional associations, publishers, and drug companies. The form. of the continuing education may be written materials (journals, books, advertisements), meetings, courses, supervisory visits, or a variety of other methods.
With this diversity of approach it is not surprising that the effectiveness of continuing education should be variable. 4 So it is natural that in many countries there is concern that more continuing education should be provided and that it should be more effective.
The approach suggested that to achieve this aim is to develop a "system" of continuing education. This term needs some explanation as it is capable of being interpreted in many ways. A system is not the same thing as an organization that provides continuing education. It is much more than that. It is the sum of the educational activities, the organizational structure that supports and manages those activities, the management, and the external agencies involved in the provision of health care. s The system should comprise a nationwide coordinated program in which technology and resources are optimally used.
Health workers themselves are aware of the importance of continued training.
A "system" of continuing education functions in the same way was an organization that provides continuing education.
FDA: Human, Animal Waste Threatens Produce
The biggest food safety risk for fresh fruits and vegetables as they are grown, picked or processed comes from human and animal waste, the US Food and Drug Administration (FDA) said Friday.
More than 9,000 Americans die each year from food-borne diseases and some scientists believe fresh produce is the biggest carrier of contamination.
The FDA issued a set of draft guidelines for US and foreign growers to carefully monitor worker hygiene, water quality, manure management and transportation.
This 34-page draft guidelines urged growers to give workers lessons on basic hygiene such as Using soap to wash their hands, covering wounds that could come into contact with produce, and using only clean toilets.
The FDA guidelines identified "the major source of contamination" for fresh produce as human or animal feces.
"We think just proper controls and proper attention to detail would make a big difference in food safety," said an FDA official. "It is our belief that these guidelines would not be very costly. "
But grower groups disagreed with the FDA's assessment. "Most food-borne disease outbreaks that happen further down the distribution line are due to contamination because people preparing food are not properly washing their hands," said Stacey Zawal, an official with United Fresh Fruit and Vegetable Association. "That is not necessarily true for growers and packers. "
Some US grower organizations have expressed concern that the agency is interfering with on- farm practices. 8 Others object to the FDA's proposal to have growers formally document the picking, handling and transportation of produce so that health officials could quickly recall foods if necessary.
Consumer groups criticized the FDA guidelines as of little use because they will not carry the force of law to But stricter regulations could evolve as researchers find new technology or methods to kill harmful bacteria or parasites, the FDA said.
The FDA recommendations are due to be made final by the FDA later this year for use by US and foreign growers. The matter of encouraging foreign growers to adopt the guidelines remains somewhat tricky but FDA officials say it is vital because of the huge amount of imported produce.
"Food-borne diseases" in this essay means those diseases
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