Using Dichotomous Key Of Flower: Fill & Download for Free

It sounds like you have not bothered to learn basic botanical terms. One has to learn these before beginning to use botanical dichotomous keys. The veins are arranged in a pinnate manner. The word is from Latin pinnatus ‘feathered’. A “pinnate” venation describes a visible pattern on a leaf where there is a dominant center vein, or “mid-rib” with other veins branching off from the middle.Avocado—-Persea americana. Family: Lauraceae.It is native to South Central Mexico. Native people in Central America domesticated them. There is evidence for three possible separate domestications of the avocado. The oldest avocado pits have been found in caves dating from around 9,000 to 10,000 years ago. It was cultivated as early as 5,000 BC. The wild native, undomesticated variety probably coevolved with extinct megafauna.Leaf arrangement: alternateLeaf type: simpleLeaf margin: entireLeaf shape: elliptic (oval)Leaf venation: pinnateLeaf type and persistence: evergreen, broadleaf evergreenLeaf blade length: 4 to 8 inchesLeaf color: greenFall color: no color changeThe sexual organs of avocado flowers are unusual in that they are active at different times of day (dichogamy). The types with the “A flowers” kind of flowers are female (receptive to pollen) in the morning and male (shedding pollen) in the afternoon. The plants with “B flowers” are male (shedding pollen) in the morning and female (receptive to pollen) in the afternoon. Here is the avocado flower.

When I became interested in this subject I started taking daily walks, and I bought some field guides. I photographed as many things as I could so that I could do the identifications at home. Field guides are wonderful aids, but the need for compact size limits their coverage. Two of my favorites are Wildflowers in the Field and Forest (though this is for New England) and The Sibley Guide to Trees (nationwide). In my opinion, you can't have too many field guides: each has unique advantages, presentation styles, and regions of coverage.You may be wondering why field guides are not obsolete in the age of internet searches, Wikipedia, and applications like LeafSnap, which automatically identifies some species based on leaf shape. But without precise botanical vernacular, search engines are relatively useless. Such a vernacular exists of course—much of it a large, synthetic branch of Latin—but it is too complex for widespread use. As yet, I am not aware of any efficient search or identification tools for unknown plants, though 1200 Weeds of North America DVD is an excellent resource for weeds. LeafSnap uses biometric analysis to automatically identify trees, but this rather compromises your goal of learning to do it yourself.So I use guides as a starting point, then I search online using a species name. This generates a lot of photos (not all of which are correctly IDed though) as well as links to botanical web sites. This is usually enough to confirm or invalidate the ID; if the latter, I still have a genus name to search on. So I alternate between books and searches until I converge on an ID.If you get really serious, you'll start using dichotomous keys, flowcharts that break down plant identification precisely. It takes years to master the jargon though, and the ID can break down if you are missing some tidbit of information, so as an amateur, I find such keys to be difficult to use. One such book, again for New England, is Flora Novae Angliae: a Manual for the Identification of Native and Naturalized Higher Vascular Plants of New England.

There are some laws in the IBO practical exams. This year’s IBO tests are likely to follow the laws.The IBO practical exams include four major parts, whose topic will be chosen from:Cell&Molecular biologyMicrobiology&BiochemistryPlant anatomy, morphology and physiologyAnimal anatomy, physiology and systematicsEcology and ethologyComparative&Functional biosystematicsThese topics can sometimes merge.The practical tasks do not cover all knowlege in the theoretical test, but the premise is you should be familiar with the theories. They usually involve:Cell&Molecular biologyMaceration and Squash techniqueSmear methodStaining of cells and slide preparationBiochemistrySeparation techniques: chromatography, filtration, centrifugationStandard tests for monosacchrides, polysacchrides, lipids, proteins (Fehling, I2 in KI(aq), biruet)TirationMeasuring quantities by drip and strip methodsDilution methodsUse of micropipettesUse of counting chambersDetermination of absorption of lightGel electrophoresisMicrobiologyPreparing nutrient mediaFlaming and heating glass mediaInoculation techniquesPlant anatomy and physiologyFlower dissection and deduction of flower formulaDissection and sectioning of roots, stems, leaves, fruitsStaining and slide preparation of plant tissuesElementary mesurement of photosynthesis and transpirationAnnimal anatomy and physiologyDissection of all invertebratesDissection of fish or organs from vertebrates bredWhole-mount slide preparation of small invertebratesElementary mesurement of respirationEthologyDetermination and interpretation of animal behaviorEcologyEstimation of polulation density and biomassElementary estimation of water and air qualityBiosystematicsUse and construction of simple dichotomous keysIdentification of insect ordersIdentification of most common flowering-plant familiesIdentification of Phyla and classes of other organismsCheck out former IBO exams to be prepared.International Biology OlympiadRemember the tasks been covered in the previous year are less likely to appear in next year’s IBO practical exams, so you can have a better focus.Sample question of cytology from 2014 IBO