INTRO TO BOTANY

• Biology


  The scientific study of living organisms, their structure, function, growth, origin, evolution, and distribution
• This subject


  • Enhances the understanding of the principles and concepts in the study of biology, particularly heredity and variation, and the diversity of living organisms, their structure, function, and evolution
• Diversity


  The variety in the structure and function of organisms that enables them to adapt and survive in the type of environment they inhabit
• Adaptive mechanisms


  The development of mechanisms for the survival and continuity of organisms, leading them to become more and more complex
• This chapter will provide emphasis on the various processes in plants and animals responsible for the maintenance and continuity of life
• Botany


  The scientific study of plants, including their structure, growth, and development
• Botanist


  A person who specializes in the study of plants
• Aristotle is considered the "Founder of Plant Science" and wrote that all plant life is lower and less specialized than animal life
• Theophrastus


  The "Father of Plant Science", who wrote "History of Plants" and "Causes of Plants", and was the most outstanding botanist in the early days of botany
• Plants


  • Are multicellular living things that come in different shapes and sizes, some short-lived and others living for hundreds of years
  • Are usually green in color
  • Have adapted to a wide variety of habitats, and methods of reproducing and dispersing themselves
• Plants


  • Columbine (short-lived, 3-4 years)
  • Sequoia (oldest known specimen 3,266 years old)
  • Great Basin Bristlecone Pine (over 5,000 years old)
  • Pando (oldest living tree colony, over 80,000 years old)
• Autotrophs


  Plants that utilize light energy and convert it to chemical energy
• Tropism


  The capability of plants to move in response to stimuli
• Plant organs


  • Leaves
  • Stem
  • Roots
  • Flowers
  • Fruits
  • Seeds
• Plant forms


  • Trees
  • Vines
  • Weeds
  • Grass
  • Conifers
  • Cacti
  • Herbs
  • Green algae

  
• Spermatophytes


  Seed plants, also called Spermatophyta
• Seed plant groups


  • Gymnospermae (seed plants without flowers)
  • Angiospermae (seed plants with flowers)
• Gymnosperms


  • Seed plants that have seeds but do not have flowers, with seeds often borne on scale-like structures called cones (e.g. pine, spruce, fir)
• Angiosperms


  • Seed plants that produce flowers as well as seeds, with the seeds contained in an enclosed structure called fruits
• Dicots


  • Form the largest group of flowering plants with a great variety, have broad leaves with netted venation, and flower parts frequently in whorls of four or five with two cotyledons

  
• Monocots


  • Have generally long narrow/linear leaves with parallel venation, only one cotyledon in the seeds, and sepal and petal generally occur in threes or multiples of three
• Seedless vascular plants


  Plants that contain vascular tissue but do not produce flowers or seeds, reproducing instead using haploid, unicellular spores (e.g. ferns)
• Nonvascular plants


  Also called bryophytes, lack roots, stems, and leaves, and reproduce with spores, needing a moist habitat (e.g. moss)
• Unifying themes of plants

  • Plants are highly integrated organisms with organized parts
  • Plants exchange energy with their environment
  • Plant metabolism is based on chemistry
  • Plants respond and adapt to their environment
  • Plants reproduce by passing genes and information to descendants
  • Plants share parts of common ancestry
• Leaves are the lateral outgrowths of the stem, typically thin, flat, and expanded green structures that are highly effective energy converters
• Parts of a leaf

  • Blade
  • Petiole
  • Stipule
  • Midrib
  • Veins
• Blade


  The broad, flat, expanded light-harvesting portion of the leaf
• Midrib


  The long, thickened structure that is a continuation of the petiole up to the opposite end of the leaf
• Veins


  The networks found in both sides of the midrib, which are continuations of the vascular tissue
• Petiole


  The stalk that attaches the leaf blade to the stem
• Stipules


  The ear-like lobes at the base of the petiole
• Variations of leaves


  • According to composition (simple and compound)
  • According to venation (parallel and netted)
  • According to texture (fleshy, succulent, coriaceous, chartaceous, membranous)
  • According to shape

  
• Stem


  The plant axis that bears buds and shoots with leaves, and at its basal end, roots; it conducts water, minerals, and food, and may also store food
• Modified stems


  • Bulb
  • Clove
  • Tuber
  • Rhizome
  • Runner/Stolon
• Root


  The organ of a plant that typically lies below the surface of the soil, with four major functions: absorption of water and nutrients, anchoring the plant, storage of food, and vegetative reproduction
• Types of roots


  • Taproot
  • Fibrous root
  • Adventitious root
• Stem structures


  • Strings
  • Clusters underneath parent plants
  • STEM
  • Modified Stems
• Rhizome


  Large creeping rootstock or underground stems (e.g. ginger)
• Runner / Stolons


  Horizontal, aboveground stems (e.g. Strawberries)
• Root's four major functions

  • Absorption of water and inorganic nutrients
  • Anchoring of the plant body to the ground, and supporting it
  • Storage of food and nutrients
  • Vegetative reproduction (asexual reprod.) and competition with other plants