The following question is based on parts of a growing primar…
The following question is based on parts of a growing primary root.I. root capII. zone of elongationIII. zone of cell divisionIV. zone of cell differentiationV. apical meristemWhich of the following is the correct sequence from the growing tips of the root upward?
Read DetailsA researcher has developed two stains for use with seed plan…
A researcher has developed two stains for use with seed plants. One stains sporophyte tissue blue; the other stains gametophyte tissue red. If the researcher exposes pollen grains to both stains and then rinses away the excess stain, what should occur?
Read DetailsAmong plants known as legumes (beans, peas, alfalfa, clover,…
Among plants known as legumes (beans, peas, alfalfa, clover, for example), the seeds are contained in a fruit that is itself called a legume, better known as a pod. Upon opening such pods, it is commonly observed that some ovules have become mature seeds, whereas other ovules have not. Which of the following statements is (are) TRUE?1. The flowers that gave rise to such pods were not pollinated.2. Pollen tubes did not enter all of the ovules in such pods.3. There was apparently not enough endosperm to distribute to all of the ovules in such pods.4. The ovules that failed to develop into seeds were derived from sterile floral parts.5. Fruit can develop, even if all ovules within have not been fertilized.
Read DetailsUse the following information to answer the question below.T…
Use the following information to answer the question below.The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8 to 25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can now enter. The uneaten seeds may subsequently germinate.If a female orchid bee has just left a Brazil nut tree with nectar in her stomach, and if she visits another flower on a different Brazil nut tree, what is the sequence in which the following events should occur?1. double fertilization2. pollen tube emerges from pollen grain3. pollen tube enters micropyle4. pollination
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