water is essential to life
91Vitamin — This article is about the set of organic compounds. For the nutritional supplement preparation, see multivitamin. For the manga, see Vitamin (manga) …
92nervous system, human — ▪ anatomy Introduction system that conducts stimuli from sensory receptors to the brain and spinal cord and that conducts impulses back to other parts of the body. As with other higher vertebrates, the human nervous system has two main… …
93plant disease — ▪ plant pathology Introduction an impairment of the normal state of a plant that interrupts or modifies its vital functions. All species of plants, wild and cultivated alike, are subject to disease. Although each species is… …
94agricultural technology — Introduction application of techniques to control the growth and harvesting of animal and vegetable products. Soil preparation Mechanical processing of soil so that it is in the proper physical condition for planting is usually… …
95Astrobiology — (from Greek gr. ἄστρον, astron , constellation, star ; gr. βίος, bios , life ; and gr. λογία, logia ) is the interdisciplinary study of life in the Universe, combining aspects of astronomy, biology and geology. [http://astrobiology.arc.nasa.gov/… …
96gardening — /gahrd ning/, n. 1. the act of cultivating or tending a garden. 2. the work or art of a gardener. [1570 80; GARDEN + ING1] * * * Laying out and tending of a garden. Though palatial gardens existed in ancient times, small home gardens became… …
97Phosphorus — This article is about the chemical element. For other uses, see Phosphorus (disambiguation). silicon ← phosphorus → sulfur …
98hormone — hormonal, hormonic /hawr mon ik, moh nik/, adj. /hawr mohn/, n. 1. Biochem. any of various internally secreted compounds, as insulin or thyroxine, formed in endocrine glands, that affect the functions of specifically receptive organs or tissues… …
99pregnancy — /preg neuhn see/, n., pl. pregnancies. the state, condition, or quality of being pregnant. [1520 30; PREGN(ANT) + ANCY] * * * Process of human gestation that takes place in the female s body as a fetus develops, from fertilization to birth (see… …
100Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity. Computer scientist Manindra Agrawal of the… …
