Orchids are unique in having the most highly developed of all blossoms, in which the usual male and female reproductive organs are fused in a single structure called the column. The column is designed so that a single pollination will fertilize hundreds of thousands, and in some cases millions, of seeds, so microscopic and light they are easily carried by the breeze. Surrounding the column are three sepals and three petals, sometimes easily recognizable as such, often distorted into gorgeous, weird, but always functional shapes. The most noticeable of the petals is called the labellum, or lip. It is often dramatically marked as an unmistakable landing strip to attract the specific insect the orchid has chosen as its pollinator.

   To lure their pollinators from afar, orchids use appropriately intriguing shapes, colors, and scents. At least 50 different aromatic compounds have been analyzed in the orchid family, each blended to attract one, or at most a few, species of insects or birds. Some orchids even change their scents to interest different insects at different times.

   Once the right insect has been attracted, some orchids present all sorts of one-way obstacle courses to make sure it does not leave until pollen has been accurately placed or removed. By such ingenious adaptations to specific pollinators, orchids have avoided the hazards of rampant crossbreeding in the wild, assuring the survival of species as discrete identities. At the same time they have made themselves irresistible to collectors.

How many orchid seeds are typically pollinated at one time?

Câu hỏi liên quan

• The word "perish" in paragraph 3 is closest in meaning to ______.

• Where did Marianne Moore grow up?

• The author states that the reason that infants need to avoid certain foods related to allergies has to do with the infant's ___________ .

ZUNIA12

• The phrase "precious charges" refers to ..............

• The word “them” in the second paragraph refers to ................

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• The passage is organized by ...........

• Which word is similar in meaning to the word “glue”?

• The word "appealing" is closest in meaning to ........

• What does the author imply about the rate hummingbirds’ wings beat?

• What can be inferred about the defense mechanisms of the sea cucumber?

• Why are otters and mussel shells included in the discussion in paragraph 3?

• What does the writer mean by saying “education quite often produces surprises”?

• What does this paragraph mainly discuss?

• According to the passage, the doers of education are .............

• According to the passage, which of the following is learning in broad view comprised of?

• The author uses the word “draw” in line 16 to mean ...............

• The word “perishable” in paragraph 1 is closest in meaning to ............

• How was the public motivated to help the health workers?

• The word "pigment" at the end of the first paragraph means________.