botany

• Botany is the scientific study of plants and the processes occurring during the plant life, including their physiology, structure, genetics, ecology, distribution, classification, and economic importance.
• Botany originated in prehistory as herbalism with the efforts of early humans to identify and later cultivate edible, medicinal and poisonous plants, making it one of the oldest branches of sciences.
• Seedling classification is based on the fate of their cotyledon after germination.
• Epigeal seedlings are those where cotyledons are raised out of the soil by extension of the hypocotyl, and are mostly dicots.
• Hypogeal seedlings are those where the hypocotyl remains short and compact, with cotyledons staying beneath the soil, and are mostly monocots.
• Modern Botany is a broad, multidisciplinary subject with inputs from most areas of science and technology.
• The results of botanical research increase and improve our supply of medicines, food, fibers, building materials, and other plant products.
• Plants are multicellular organisms in the kingdom Plantae that uses photosynthesis to make their own food.
• There are over 300,000 species of plants: common examples of plants include grasses, trees, and shrubs.
• “Plants” to most people, means a wide range of living organisms from the smallest bacteria to the largest living things.
• Plants are autotrophs; they produce their own food via photosynthesis.
• Plants are multicellular organisms with eukaryotic cells.
• A eukaryotic cell is a relatively large cell with a true nucleus and other organelles that perform specific functions.
• Plants, protists, fungi, and animals all have eukaryotic cells.
• The concept of a scientific study can be understood by examining earlier approaches to studying nature.
• The fundamental tenets of scientific method are: all accepted information can be derived only from carefully documented and controlled observations or experiments, only tangible phenomena and objects are studied, physical forces that cannot control the world are constant through time and are the same everywhere, experiments done at one time and place should give the same results if they are carefully repeated at a different time and place, and the fundamental basis of scientific method is skepticism.
• Dicots have a taproot system, while Monocots have a fibrous root system.
• Storage Roots are a type of modified root that many plants, such as the common beet, use for storing food and water.
• Prop Roots or Buttress Roots, found in the Kapok tree, are aerial roots that support tall, top-heavy plants and transport additional nutrients and water to the stem after making contact with the soil.
• Aerial Roots for Water Retention, found in orchids, spread along the surface of the bark and often dangle freely in the air.
• Aerial Roots for Support, found in the Banyan Tree, provide increased architectural support and absorptive capacity.
• Pneumatophore Roots, also known as air roots, are produced by trees that inhabit tidal swamps and enable the root system to obtain oxygen, which is lacking in thick, waterlogged mud.
• Hausteria, or Rafflesia, are roots of parasitic plants that have become highly modified and must adhere firmly to their host either by secreting an adhesive or by growing around a small branch or root.
• Mycorrhizae are roots of most species of seed plants that have a symbiotic relationship with soil fungi in which both organisms benefit.
• Ectomycorrhizal Roots are a type of Mycorrhizae where fungal hyphae (slender, thread-like cells) penetrate between the outermost root cortex cells but never invade the cells themselves.
• Endomycorrhizal Roots penetrate the endodermis, not past Casparian strip, and help the plant in diverse stresses like drought, salinity, etc.
• Root Nodules, usually seen in legumes, occur in a small number of plants, especially legumes, and represent a symbiotic relationship with nitrogen-fixing bacteria of the genus Rhizobium.
• Scientific studies begin with a series of observations, followed by a period of experimentation mixed with further observation and analysis.
• A hypothesis is constructed to account for observations, must make prediction that can be tested, must be tested in various ways, must be consistent with further observations and experiments, and must be able to predict the results of future experiments.
• A catkin is a compact unisexual, often hanging, spike which matures and falls as a single unit.
• Flowers can be either male (staminate) or female (carpellate).
• A spike is a raceme but the flowers develop directly from the stem and are not borne on pedicels.
• A spadix is a spike-like inflorescence with imperfect flowers.
• A panicle is a branched raceme in which each branch has more than one flower.
• An umbel is an inflorescence stalk that ends in a small, rounded portion from which arise numerous flowers.
• A head is similar to umbels except that the flowers are sessile and attached to a broad expansion of the inflorescence stalk.
• Microsporogenesis is the process inside the anthers where the pollen sac or the sporangia contain the microsporocyte which undergoes meiosis to produce four microspores.
• The vegetative cell is found in pollen grains and produces an elongated pollen tube, a gametophytic cell, to deliver the male gametes to the embryo sac.
• The generative cell is found in pollen grains and produces two sperm cells, or male gametes.
• Megagametogenesis is the process in the female part of the flower where the megasporocyte (inside the megasporangium) undergoes meiosis to produce four megaspores, only one of which will remain, the others will degenerate.