Who is Study plants anatomy

Plant anatomy, which is concerned chiefly with the internal structure of plants, was established through the efforts of several scientific pioneers. Early plant anatomists of note included Marcello Malpighi (1628–1694) of Italy, who discovered various tissues in stems and roots plants, and Nehemiah Grew (1628–1711) of England, who described the structure of wood more precisely than any of his predecessors (Fig.1).

Today, a knowledge of plant anatomy is used to help us find clues to the past, as well as for many practical purposes. For example, the related discipline of dendrochronology deals with determining past climates by examining the width and other features of tree rings. We can also learn much from archaeological sites by matching tree rings found in the wood of ancient buildings to the rings of wood of known age. Plant anatomy is also used to solve crimes.

Forensic laboratories may use fragments of plant tissues found on clothing or under fingernails to determine where a crime took place or if certain persons could have been present where the crime was committed. The anatomy of leaves, stems, and other plant parts is currently being used to unravel and sort out relationships among plants. A form of plant anatomy, known as paleobotany, involves the study of plant fossils.

Figure 1 Anatomy: A thin section of Magnolia wood as seen through a microscope, ×40.
Figure 1 Anatomy: A thin section of Magnolia wood as seen through a microscope, ×40.

Plant physiology anatomy, which is concerned study with plant function, was established by J. B. van Helmont (1577–1644), a Flemish physician and chemist, who was the first to demonstrate that plants do not have the same nutritional needs as animals.

In a classic experiment study, van Helmont planted a willow branch weighing 5 pounds in an earthenware tub filled with 74.4 kilograms (200 pounds) of dry soil. He covered the soil to prevent dust settling on it from the air, and after 5 years, he reweighed the willow and the soil. He found that the soil weighed only 56.7 grams (2 ounces) less than it had at the beginning of the experiment but that the willow had gained 164 pounds. He concluded that the tree had added to its bulk and size from the water it had absorbed. We know now that most of the weight came as a result of photosynthetic activity, but van Helmont deserves credit for landmark experimentation in plant physiology.

Modern plant physiologists have learned how to isolate and clone genes (units of heredity that are found within the nuclei of cells) and are using the knowledge gained to learn in precise detail much more about plant functions, including how plants conduct materials internally; how temperature, light, and water are involved in growth; why plants flower; and how plant growth regulatory substances are produced, to mention just a few.

European explorers of other continents during past centuries took large numbers of plants back home with them, and it soon became clear to those working with the plants that some sort of formalized system was necessary just to keep the collections straight. Several plant taxonomists (botanists who specialize in the identifying, naming, and classifying of plants) proposed ways of accomplishing this, but we owe our present system of naming and classifying plants to the Swedish botanist Carolus Linnaeus (1707–1778).

Plant taxonomy (also called plant systematics), which is the oldest branch of plant study, began in antiquity, but Linnaeus did more for the field than any other person in history. Thousands of plant names in use today are those originally recorded in Linnaeus’s book Species Plantarum, published in 1753. There are still thousands of plants, fungi, and other organisms that have not yet been described or even discovered.

Although it obviously is already too late to identify species that were not described before they became extinct, plant taxonomists around the world have united to try to identify and describe as many new organisms—many with food, medicinal, and other useful potential—before much more of their natural habitat disappears. Other plant taxonomists, through the use of cladistics (analysis of shared features) and molecular techniques, are refining our knowledge of plant relationships and are contributing to the improvement of many of our food crops. Plant taxonomists often specialize in certain groups of plants. For example, pteridologists specialize in the study of ferns, while bryologists study mosses and plants with similar life cycles.

The discipline of plant geography, the study of how and why plants are distributed where they are, did not develop until the 19th century (Fig. 2). The allied field of plant ecology, which is the study of the interaction of plants with one another and with their environment, also developed in the 19th century. After the publication in 1962 of a best-seller entitled Silent Spring (authored by Rachel Carson), public awareness of the field of ecology as a whole increased considerably. In this book, based on more than 4 years of literature research, Ms. Carson called attention to the fact that more than 500 new toxic chemicals annually are put to use as pesticides in the United States alone, and she detailed how these chemicals and other pollutants were having an insidious impact on all facets of human life and the environment.

The study of the form and structure of plants, plant morphology, was developed during the 19th century, and during the 20th century, much of our basic knowledge about the form and life cycles of plants was incorporated in the plant sciences as we know them today. During this time, the number of scientists engaged in investigating plants also greatly increased.

Genetics, the science of heredity, was founded by the Austrian monk Gregor Mendel (1822–1884), who performed classic experiments with pea plants. Today, various branches of genetics include plant breeding, which has greatly improved yields and quality of crop plants, and genetic engineering. Genetic engineering includes the introduction of genes from one organism to another and has already improved the pest, frost, and disease resistance, as well as yields, of some crop plants. It holds enormous potential for continued development of better agricultural, medicinal, and other useful plants. Future control of human, animal, and plant diseases is also anticipated.

Figure 2: Ecologists, plant geographers, and other biologists recognize large communities of plants and animals that occur in areas with distinctive combinations of environmental features. These areas, called biomes, are represented here by the tropical rain forest, which, although occupying less than 5% of the earth’s surface, is home to more than half of the world’s species of organisms.
Figure 2: Ecologists, plant geographers, and other biologists recognize large communities of plants and animals that occur in areas with distinctive combinations of environmental features. These areas, called biomes, are represented here by the tropical rain forest, which, although occupying less than 5% of the earth’s surface, is home to more than half of the world’s species of organisms.

Cell biology (previously called cytology), the science of cell structure and function, received a boost from the discovery of how cells multiply and how their various components perform and integrate a variety of functions, including that of sexual reproduction. The mid-20th-century development of electron microscopes further spurred cell research and led to a vast new insight into cells and new forms of cell research that continues to the present.

Economic Botany and ethnobotany, which involve practical uses of plants and plant products, had their origin in antiquity as humans discovered, used, and eventually cultivated plants for food, fiber, medicines, and other purposes.

Today, research is being conducted on the uses of plants by indigenous peoples with an eye to discovering medicines and other useful plant products previously unknown in developed countries. There is still a vast amount of botanical information to be discovered. For example, 11,000 papers on botanical subjects were published in 1938 alone, and the number per year in recent times is much greater.

It also appears probable that at the start of the 21st century, at least one-third of all the organisms regarded in the past as plants (particularly algae and fungi) have yet to be named, let alone thoroughly investigated and understood.

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