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Botany Botany bottany_dan 2/16/06 2:54 PM Page 13 The NYC Department of Parks & Recreation presents ™ urban park rangers • education program BBOOTTAANNYY Plant Power nce standards accept academic performa ed s meet ogram City Department of Education, including: pr w York ese e Ne A th th Map Reading and Making • Critical Thinking • Plant Identification ct in by ivit ns d Researching and Writing a Field Guide • Graphing • Site Evaluation ies and lesso use and Creating a Timeline • Data Gathering • Natural Science • Measuring Calculating • Social Science • History • Art City of New York City of New York The New York City Parks & Recreation Parks & Recreation Department of Education Urban Park Rangers bottany_dan 2/16/06 2:54 PM Page 2 11 WWhhaatt iiss tthhee NNaattuurraall CCllaassssrroooomm?? The Natural Classroom is a series of educational programs developed by the Urban Park Rangers to immerse students in the living laboratory of the natural world. These programs combine standards-based education with hands-on field lessons taught by Urban Park Rangers. Based on natural and cultural topics that are visibly brought to life in our parks, The Natural Classroom is designed to stimulate, motivate and inspire your students to apply their developing skills in English, Math, Science and History to real-life critical thinking challenges. The activities in Botany: Plant Power! focus on the following skills: • Creating and Reading Graphs, Measuring, and Making Calculations • Exploring Living Science Concepts by creating Field Guides, and Gathering Data in the field Writing and Drawing How to Use This Natural Classroom Program Guide Find Your Level: Level One = Grades K-2 Prepare for Adventure: Review the park visit descrip- Level Two = Grades 2-6 tion a few days before the trip so you will be aware of the Level Three = Grades 6-8 day’s anticipated activities. Let your students know how to dress for the weather, the bugs, and the terrain – you will be Word Challenge: Important vocabulary words are pro- outdoors in the “wilds” of New York City parks. vided and listed in order of appearance. Let your students find the definitions and begin their adventure. Wrap it up: Have your students map, graph, illustrate, chart and analyze their way to thoughtful conclusions using Focus on The Big Picture: Read the teacher text to the post-visit activities. learn about the three main program concepts, introduce them to your class and get them thinking in context. On and Beyond: Loved your park experience and the learning topic so much that you want more? We have includ- Take Action: Have your students research, write, meas- ed extension activities that expand the scope of the in-class ure, build, and create using the pre-visit activities. Each proj- program. ect is designed to actively engage the group in planning for their park visit. llenge ord Cha W Key Botany Vocabulary Words photosynthesis gymnosperms anther native chlorophyll spores stigma non-native cellular respiration pollinated pollen invasive oxidizing germinating fruit angiosperms seed dispersal *Words will be italicized throughout program bottany_dan 2/16/06 2:54 PM Page 11 ure CON 2 ig Pict CEP the B T cus on Plants are Essential Fo 1 Botany is the science or study of plants Plants do not use all of the energy captured for growth; some is expended as the plant Plants, unlike animals, are able to make their "breathes," which is called cellular respiration own food. Plants capture energy found in sun- (cellular respiration is the process of oxidizing light through a process called Photosynthesis. food molecules into carbon dioxide and water.) Photosynthesis means “putting together” (syn- thesis) using “light” (photo). All animals rely on the energy plants have cap- tured. When an animal, such as a squirrel, eats The energy from the sun’s rays is captured, or a plant, such as an acorn, it converts the plant absorbed, by the pigment chlorophyll, found in to energy essential for growth. Animals cannot leaves. Chlorophyll causes the plant to appear digest all the parts of a plant, so some energy is green. This energy is then used to synthesize a lost. sugar molecule from molecules of water and carbon dioxide. When a second animal (such as a hawk) eats the first animal, the This equation illustrates the chemistry of photo- second animal converts the first synthesis: animal to energy, thus ulti- CO2 + H2O in the presence of light & chlorophyll -> CH2O + O2 mately using energy that was (Carbon Dioxide + Water + sunlight -> Sugar and Oxygen) originally stored in the plant. The hawk does not use all The Mathematics of Energy the energy stored in the squirrel. In the transfer Ecologists estimate only 10% of the energy at one trophic of energy along the level (such as primary producers, or plants) is passed on to the next higher trophic level (such as primary consumers, or food chain, some of herbivores). the energy is lost. By multiplying by 10 for each trophic level the energy had to pass through, we can calculate how much plant material was needed to produce an organism at a particular trophic level. PT 2 CE N TThhee LLiiffee CCyyccllee ooff FFlloowweerriinngg PPllaannttss O C The majority of plants are called Angiosperms, occur. Pollination is the process by which pollen meaning they have flowers. Unlike ferns (or from the male part of the flower, the anther, is Gymnosperms) that have spores, angiosperms transferred to the female part of the flower, the produce flowers, when pollinated. stigma. The flowers of some plants have fra- grances or bright colors that attract insects, Flowering plants start life by germinating bats, or birds. These animals then transfer the (sprouting) from a seed. The seed contains food pollen from flower to flower. In other plants, needed to develop the roots and a shoot. The pollen is transported by wind. roots transport water and nutrients from the soil to the rest of the plant. The shoot grows After pollination, parts of the flower swell to and begins to develop leaves. form a seed and a fruit. The seed is the embryo of a new plant, packaged with a supply of food As the plant grows, it produces flowers and and protected by a hard coat. The fruit is the seeds. Some plants mature in just a few flesh surrounding the seeds that protects them months, while trees may take many years to and aids in dispersal. Seeds and fruits come in reach maturity. all shapes and sizes to facilitate seed dispersal. Seed dispersal is the transportation of the seed In order to produce seeds, pollination must from its plant of origin to another location. bottany_dan 2/16/06 2:54 PM Page 4 3 Seed Dispersal Methods Some seeds are dispersed by the wind. These seeds are either light and fluffy like parachutes (such as dandelions) or have wings or blades like a helicopter (such as maples). Plants with “discharge” seed dispersal have specialized parts that release their seeds into the envi- ronment around them. For example, jewelweed plants are sensitive to touch and release their seeds when you brush past them. Animals help disperse seeds in three ways. Some seeds, such as burrs, have tiny hooks on them to hold onto the fur of an animal until they are brushed off in a new location. Other seeds, like those encased in a fruit, are eaten by animals. These seeds then pass through the digestive tract of the animal and are excreted in a new location. Finally, some seeds, like acorns, are buried and saved for food by animals like squirrels. Not all of these seeds will be eaten; the uneaten seeds may germi- nate and grow into a plant. CON CEP T PPllaannttss iinn tthhee CCiittyy 3 Plants are an important part of life in a city. They are an important source of oxygen, and Neighborhoods in New York City with more even help clean the air by filtering out pollu- trees have fewer children with asthma. tants. In addition, plants, particularly trees, pro- vide shade from the sun, help keep noise down, and provide wildlife habitat. London Plane Plants, such as trees and flowers, are also important because they are aesthetically pleas- + = ing and are a way for city dwellers to connect Plane Sycamore with nature. Scientific studies have shown that access to greenspace can increase self-esteem DID YOU KNOW? and academic performance, and decrease vio- The London Plane tree is a hybrid (combination) of the lent behaviors. native Sycamore tree and the non-native Plane tree. This tree can be found living all over New York City and There are still many wild acres of parkland in although not native to this area, it was planted because it New York City. You can visit these areas and see is resistant to pollution and disease. native plants growing in much the same way they have grown for centuries. In the manicured areas of our parks, you can see many examples of non-native plants, admired and brought in from other regions and planted for our enjoyment. Occasionally, these plants do so well in their new homes that they grow out of control and spread to other areas where they are not wanted. When this hap- pens, the plants are considered invasive. bottany_dan 2/16/06 2:54 PM Page 9 4 ction Take A Pre-Visit Activities The following pre-park visit activities will pre- Weather Conditions: Is it pouring rain? Blistering pare your students for their trip to the park. hot? These conditions will also affect what you are likely to observe (e.g. plants may wilt in Setting up a Field Journal extreme heat).
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