PL SC 221

The flashcards below were created by user hcunning on FreezingBlue Flashcards.

  1. Anaphase
    The time it takes for paired chromosomes to split and move to opposite poles of the cell along the microtubule spindle.
  2. Cell Wall
    Contain complex carbohydrates like cellulose, pectin, and lignin that provide structural rigidity to each cell. 
  3. Central vacuole
    Membrane-bound, fluid-filled organelle that provides structure within the plant cell and store both water and nutrients.
  4. Chlorenchyma
    When chloroplasts are found in parenchyma cells, the cells are called chlorenchyma.
  5. Chloroplasts
    Cellular organelles where photosynthesis  occurs, unique to plant cells
  6. Collenchyma
    These cells have unevenly thickened cell walls and are living
  7. Cytokinesis
    Last stage of cell division, each new cell forms an enveloping plasma membrane, cell plate begins to develop b/w the two membranes where new cell-wall material begins to be manufactured.
  8. Cytoplasm
    Fluid matrix in the cell, chloroplasts and mitochondria and ribosomes circulate within the cytoplasm.
  9. Cytoplasmic Streaming
    Indicated by movement of chloroplasts within the cell.
  10. Daughter Cells
    Product of cell division, two identical daughter cells formed from a single parent cell.
  11. Equilibrium
    Equal concentration of of chemicals or solute concentration within a space or across a membrane
  12. Fiber
    Type of Sclerenchyma cell, a long narrow cell
  13. Interphase
    Only phase that's not a part of mitosis, nucleus appears as a dark mass and the nucleolus may be visible. DNA replication occurs here but is not visible.
  14. Lipid
    Fats, what the cell membrane is mostly composed of.
  15. Lumen
    In a sclerenchyma cell (which is dead), the lumen is the cavity where the cytoplasm once was.
  16. Metaphase
    Occurs when all chromosomes become aligned along the middle axis of the nucleus, ~halfway along the spindle.
  17. Metaphase Plate
    The line-up of chromosomes that occurs in metaphase, a way to organize all chromosomes to ensure each new cell will have a copy of each chromosome.
  18. Microtubule
    In prophase, microtubules form a spindle spanning the interior of the cell  with two anchor points at opposite poles of the cell.
  19. Microtubule Spindle
    The spindle formed along the interior of the cell in prophase
  20. Mitosis
    Process by which cells undergo division to produce two identical daughter cells from a single parent cell.
  21. Nucleolus
  22. Nucleus
  23. Parenchyma
    These cells are thin-walled and are living at maturity
  24. Parent cell
    The cell that undergoes division (mitosis) to produce two identical daughter cells
  25. Plasma Membrane
    Also called plasmalemma, right inside the cell wall, cell-wall materials are formed and added by the membrane.
  26. Plasmodesmata
    Pores in the cell walls between two cells where water and materials are exchanged across plasma membranes of the adjacent cells.
  27. Prophase
    Chromosomes thicken and become visible, nucleolus disappears. Microtubules form a spindle.
  28. Respiration
  29. Sclereid
    Type of sclerenchyma cell, are various shapes
  30. Sclerenchyma
    Cells are dead at maturity, have thick cell walls, can be composed of two different types: a) fibers b) sclereids
  31. Solute
  32. Solution
  33. Telophase
    Occurs when all chromosomes have arrived at the two poles and new membranes have formed around the daughter nuclei. Spindle disappears and various organelles are replicated and sorted to each side of the cell.
  34. Middle Lamella
    Non-living area between adjacent cells, filled with Ca2+ and Mg2+ pectates which cements adjacent cells together. Makes plants rigid.
  35. Symplast
    Continuum of living material, minerals and metabolites can be transported throughout the plant without leaving the cytoplasm.
  36. Apoplast
    Non-living parts of plant tissue. Ex middle lamella and dead xylem vessels.
  37. Plasmalemma
    Made of three major componants: Lipids (40%) Proteins (40%) and Carbohydrates (20%)
  38. Lipids (plasmalemma)
    Arranged in bilayer, polar portions face out and non-polar portions face in (unit membrane). Lipid mixture contains phospholipids, glycolipids, sterols.
  39. Phospholipid
    Most common membrane lipid. Contains a charged, polar head and two hydrophobic hydrocarbon tails. Can be saturated or unsaturated (kinked).
  40. Glycolipid
    Has sugar as a polar group, hydroxyl head for polar part. Non-polar conjugated rings as non-polar part.
  41. Proteins (plasmalemma)
    Most are enzymes that have important roles in transport of metabolites across the membrane. Some proteins extend through membrane from one side to the other, some confined to outside or inside membrane.
  42. Carbohydrates (plasmalemma)
    Linked to proteins and lipids. Helps position protein so it's linked to the polar part of the membrane, can help form 3D structure.
  43. Liquid Crystalline State
    Proteins can move in the phospholipid matrix and the whole membrane is very fluid.
  44. Solid Gel Phase
    Occurs @4°C (in tomatoes anyways), gelling brings most membrane activities to a standstill and increases permeability of the membrane.
  45. Cell Wall
    Provides structure/support, protects contents of plant.
  46. Cellulose
    Main structural component of cell walls
  47. Hemicellulose
    Glue-like substance, holds cellulose fibrils together (cell wall)
  48. Pectin
    Organic material that gives stiffness to fruit jellies
  49. Glycoproteins
    Proteins that have sugars associated with their molecules
  50. Nucleus
    Bound by two membranes (nuclear envelope), contains nucleoplasm (granular-appearing fluids)
  51. Nucleoli
    Composed primarily of RNA and associated proteins.
  52. Endoplasmic Reticulum
    • Facilitates cellular communication and channeling of materials 
    • - can have ribosomes on surface (rough ER) or no ribosomes (smooth ER)
    • - synthesizes a diverse array of lipids
  53. Ribosomes
    Composed of 2 subunits made of RNA and proteins. Initiate protein synthesis in association with special RNA molecules.
  54. Dictyosomes
    Stacks of flattened discs/vesicles, "Golgi apparatus", involved in the modification of carbohydrates attached to proteins that are synthesized and packaged in the ER.
  55. Plastids
    Several kinds in most plants, chloroplasts the most conspicuous
  56. Grana
    Stacked in chloroplasts, each granum contains 2-100 thylakoids
  57. Thylakoid Membrane
    Contain chlorophyll and other pigments. Inside, first steps of photosynthesis take place.
  58. Stroma
    Liquid phase of the chloroplast, contains enzymes involved in photosynthesis.
  59. Mitochondria
    Energy released from them as they undergo cellular respiration on organic molecules, this energy keeps individual cells and whole plant functioning.
  60. Microbodies
    Small, spherical organelles: contain specialized enzymes bounded by a single membrane.
  61. Peroxisomes
    (microbody) contain enzymes needed by some plants to survive during hot conditions -> photorespiration
  62. Glyoxisomes
    (microbody) contain enzymes that aid in the conversion of fats to carbohydrates
  63. Vacuoles
    • Take up 90% or more of cell, bounded by vacuolar membranes, help maintain cell pressure or pH, storage for cell metabolites and waste products.
    • - contain "digestion" enzymes incl. proteases, nucleases, glycosidases, lipases. These break down and recycle cellular components.
  64. Tonoplast
    Vacuolar membrane
  65. Cytoskeleton
    Intricate network made mainly of microtubules and microfilaments.
  66. Why are enzymes adversely affected by the phase change?
    Tertiary protein structure altered by the phase change; active sites become buried/altered so they can no longer bind substrate.
  67. Critical temperature
    Temperature at which the phase transition occurs (from liquid crystalline to solid gel phase)
  68. Uses of phenolic compounds in plants?
    • (like alkaloids, cyanogenic glycosides, protase inhibitors)
    • discourage insect and animal herbivores
  69. Use for chitanase and glucanase in plants?
    Are cell-wall degrading enzymes, used to destroy pathogenic fungi and bacteria
  70. Use of latexes in plants?
    Are wound-clogging emulsions of hydrophobic polymers, possess insecticidal and fungicidal properties, also antiherbivory agents.
  71. Anthocyanin
    Pigment found in vacuoles of many plant cells (like flowers and fruit).
  72. Proplastid
    Precursor of all other plastids
  73. Amyloplasts
    Unpigmented plastids, contain starch granuoles. Common in storage organs like potato tubers
  74. Leucoplasts
    Colourless plastids involved in synthesis of monoterpenes
  75. Monoterpenes
    Volatile compounds in essential oils, found in secretory glands assoc. with leaf and stem trichores, also found in citrus plants
  76. Chromoplasts
    synthesis + accumulate corotenoid and xanthophyll pigments making them warm colours. Found in ripe tomatoes, carrots, red peppers
  77. Etioplasts
    plastids where development from proplastids to chloroplasts has been arrested by absence of light. Contain no chlorophyll but have colourless chlorophyll precursor (protochlorophyllide). Light triggers development of etioplasts into chloroplasts.
  78. PSI and PSII
    • Photosystem I: ATP synthesis, in the unstacked stroma 
    • Photosystem II: Occurs first, takes place in the stacked grana thylakoid membrane
  79. Light Reactions
    Capture of light energy and its conversion to chemical energy (ATP and NADPH)
  80. Dark Reactions
    Enzymatic fixation of CO2 into carbohydrate, utilizing the ATP and NADPH from the light rxns
  81. Shoots: Apical or Terminal Bud
    Leaves originate from the apical/terminal bud of the stem.
  82. Shoots: Meristem
    Tissue that contains actively dividing cells
  83. Shoots: Nodes
    The locations where leaves are attached
  84. Shoots: Auxillary Bud
    Branch stems arise from auxillary buds, located at the nodes along main stem in the axils of leaves
  85. Shoots: Axil
    Point where the leaf joins the stem, in dicots there is an auxillary bud in each axil
  86. Shoots: Internodes
    Area between the nodes
  87. Shoots: Floral Buds
    Many form from either the auxillary or apical meristems.
  88. Meristems: Apical Meristem
    Found in root tips and stem tips. Generates stem tissue and initiates formation of new leaves.
  89. What are the 3 primary/transitional meristems?
    Protoderm, ground meristem, procambium
  90. Meristems: Protoderm
    Forms the epidermis/outer protective layer covering of a growing root or shoot.
  91. Meristems: Ground Meristem
    Forms the cortex/main bulk of plant. Consists of parenchyma cells, collenchyma cells, sclerenchyma cells.
  92. Meristems: Procambium
    Produces the vascular tissue that consists of xylem and phloem.
  93. Meristems: Auxin
    Plant hormone that inhibits growth of auxillary buds
  94. Meristems: Cytokinin
    Plant hormone that promotes growth of auxillary buds. Builds up in axial buds when it's going to grow out.
  95. Meristems: Lateral Meristems
    Produce secondary growth, increases diameter of stems and roots of woody plants
  96. Meristems: Intercalary Meristems
    Occur between mature tissues, facilitates longitudinal growth of plant organ independant of the activity of the apical meristem. Consists of both new and mature cells. Occurs in grasses and related plants
  97. Angiosperms
    Flowering plants. Seeds enclosed in an ovary.
  98. Angiosperms: Monocots
    No secondary growth in roots and shoots, one cotyledon.
  99. Angiosperms: Dicots
    Can have secondary growth in roots and shoots. Two cotyledons.
  100. Gymnosperms
    "naked" seeds (not enclosed in an ovary). Can have secondary growth in roots and shoots.
  101. Functions of Roots
    • - anchor plants in soil
    • - absorb water and mineral nutrients from soil
    • - conduct water and minerals to and from the shoots
    • - provide area for storage
  102. Roots: Root Cap
    protective layer of cells produced from the root tip to prevent damage to the apical meristem as roots push through soil. Also area where gravity is perceived by plant
  103. Roots: Region of cell division
    Located behind the root cap, includes apical meristem and area right above it, meristematic region where cells divide every 12-36 hrs
  104. Roots: Cell elongation
    Located above the area of cell division. Region where cells elongate, causing root to lengthen
  105. Roots: Cell maturation
    Located above the region of cell elongation, where primary tissues mature into secondary tissues. Where root hairs are formed (extension of the epidermal cell, increases root surface area)
  106. Epidermis
    Outer absorbing layer of root, consisting of single layer of cells, covers entire root except for root cap. Can have root hairs.
  107. Cortex
    Large thin-walled parenchyma cells found to the inside of the epidermis. Loosely packed to allow for water and minerals to move through without entering the cells. Functions in food storage.
  108. Hypodermis
    Outermost layer of the cortex (sometimes formed), specialized protective layer. Hypodermal cells lined with subarin, which slows water and nutrient loss from the root.
  109. Apoplastic (movement of water)
    Movement through cell walls and intercellular spaces, resistance to flow 50% less than symplastic
  110. Symplastic (movement of water)
    Movement through living cells, secondary route for water movement due to greater resistance to water flow.
  111. Endodermis
    Innermost layer of cortex. Single layer of cells that form a boundary b/w the cortex and the vascular cylinder.
  112. Vascular tissue
    Xylem and phloem
  113. Pericycle
    One or more layers of cells that surround the vascular tissues. The location from which lateral or branch roots arise. Generates vascular cambium in plants undergoing secondary growth.
  114. Pith
    Ground tissue located in the center of the root
  115. Cuticle
    A waxy layer present on the epidermal cells of a stem. Not on roots.
  116. Xylem
    A transport tissue that conducts water and minerals from the roots to the leaves. Xylem is non-living. Primary xylem consists of fibres and parenchyma cells.
  117. Tracheids
    Type of conducting cell in xylem. Are elongated with a tapered end.
  118. Vessel Elements
    Type of conducting cell in xylem. Larger than tracheids, lack end walls, form a continuous pipeline for transport.
  119. pit pairs
    in vascular elements, in secondary cell wall regions where no secondary cell wall was deposited. Has openings in it that water can freely move through.
  120. Phloem
    Transport tissue that conducts organic nutrients, usually from leaves to roots. Living at maturity.
  121. Sieve-tube-cells
    What phloem is made up of, have associated companion cells. The ends of these cells form a plate with holes to resemble a sieve.
  122. Companion Cells
    Smaller + closely connected to the sieve-tube-cells, nucleus of companion cells controls and maintains both cells
  123. Stolon
    Above ground stem modification. Horizontal stem that grows above ground. New plants produced where nodes touch the ground ex. strawberry
  124. Tendrils
    Above ground stem modification. Branch that is capable of clinging or coiling around structures to provide additional support ex. grapes
  125. Rhizomes
    Below ground stem modification. Horizontal stem below ground. Roots and shoots develop from the nodes. Store food for shoot growth following periods of stress.
  126. Bulbs
    Below ground stem modification. Compressed stem surrounded by fleshy leaf-like structures (scales) -> enclose shoot or flower buds. Outer scales protect, inner scales store food resources.
  127. Primary Growth
    Growth in height (apical meristem)
  128. Secondary Growth
    Horizontal growth (girth)
  129. Cork Cambium
    Originates from parenchyma cells in cortex, regained meristematic activity
  130. Lenticels
    Perforations in cork to help gas exchange
  131. Wood
    Everything inside vascular cambium. Differences b/w angiosperms and gymnosperms (hardwood, softwood)
  132. Early Wood
    Larger vessels, lighter in appearance
  133. Late Wood
    More fibres, darker in appearance
  134. Heartwood
    Nonfunctional, programmed death of parenchyma cells in wood. Reserve substances withdrawn from the area of heartwood formation, or can be converted into heartwood substances.
  135. Sapwood
    Functional water conductive tissue, usually limited to the outermost growth rings.
  136. Tylosis
    Protoplasts of adjacent parenchyma ells grow into xylem conduits and seal off injured/disfunctional cells
  137. Tubers
    Swollen fleshy portions of underground stems. Functions as storage organ (lots of starch) ex. irish potato
  138. Corms
    Short swollen underground stem. Plant structures form from axillary buds and grow by using food resources from the corm. Wither and die @ end of season, new corms form at base of each flowering stem.
  139. Main functions of leaves
    Photosynthesis and Transpiration
  140. Phyllotaxy
    Pattern, leaf position on stem due to chemical concentration changes
  141. Guard Cells
    Regulate opening and closing of stomata, allowing gases to move in and out of the leaf. Open and close in response to environmentally induced pressure changes
  142. ABA
    abscisic acid (plant hormone). Causes stomates to close by inhibition of the proton pump in the plasma membrane.
  143. Components of Leaf Internal Anatomy
    Mesophyll tissue, intercellular spaces, vascular tissue
  144. Palisade layer
    1 of 2 regions of mesophyll tissue in a dicot leaf. Upper region of elongated cells vertically arranged in 1-2 compact layers, contains more than 80% of the chloroplasts
  145. Spongy Layer
    1 of 2 regions of mesophyll tissue in a dicot leaf. Lower region of irregular shaped cells loosely arranged. Contains fewer chloroplasts.
  146. Intercellular Spaces
    Abundant in spongy mesophyll layer as results of irregular shaped loosely packed arrangement of cells. Large # of air spaces in leaf increase surface area available for gas exchange.
  147. C3 Plant
    Less efficient in fixing carbon (making sugar). Lose 600g water for same amount of grams CO2 fixed as a C4 plant. Only use RuBP to fix CO2
  148. RuBP Carboxylase
  149. C4 Plant
    Twice as efficient in fixing carbon (making sugar) as a C3 plant. Only use 300g water by evaporation for every gram CO2 fixed by photosynthesis. First use PEP carboxylase then use RuBP carboxylase  in bundle sheath cells
  150. CAM
    Crassulacean acid metabolism
  151. Brassicaceae
    Mustard Family (largest array of veggies produced from this family)
  152. Which tissues in an angiosperm develop into the seed coat?
    The inner and outer integuments
  153. Microsporagenesis
    Happens in male gametes
  154. Megasporagenesis
    Happens in female gametes
  155. Spike
    • ex. wheat
    • Unbranched, flowers attached directly to central axis (no pedicels)
  156. Raceme
    Unbranched, flowers attached by pedicels to the central axis
  157. Panicle
    • ex. rice
    • Branched Raceme
  158. Umbel
    • ex. carrot
    • Flowers attached by pedicels which arise from common point, simple or compound
  159. Corymb
    • ex. cherry
    • Unbranched, pedicels of unequal length alternately attached along central axis, forms a flat-topped cluster
  160. Head
    • ex. sunflower
    • Peduncle with flowers attached directly to a broad receptacle
  161. Receptacle
    Regions where floral parts are attached
  162. Sepals
    Outermost whorl of floral parts, protect inner part of flower (collectively: calyx)
  163. Corolla
    Collective term for petals
  164. Apetalous
    No petals ex. wheat
  165. Sympetalous
    Petals partially or completely fused ex. petunia
  166. Choripetalous
    Petals are seperate ex. marshmallow
  167. Regular
    All floral parts of similar shape and size (mirror image on all axis's)
  168. Irregular
    Not all floral parts same shape and size (on some axis, not mirror image)
  169. Stamen
    Pollen-bearing structure, incl. anther and filament, collectively called the androecium (male house)
  170. Pistil
    Incl. ovary, stigma, style.
  171. Carpels
    Chambers in the ovary that contain the ovules, collectively called the gynoecium (female house)
  172. Complete Flowers
    Contain all floral components incl. sepals, petals, stamens, and carpels
  173. Incomplete Flowers
    Will be missing one or more floral components
  174. Perfect Flowers
    Have male (stamen) and female (pistil) reproductive structures
  175. Imperfect Flowers
    Have only female (pistillate flowers) or male (staminate flowers) reproductive structures
  176. Ovary
    (pericarp) develops into the fruit
  177. Ovule
    develops into the seed
  178. Pericarp
    • Fruit wall = ovary wall
    • Made of 3 layers:
    • 1. Endocarp (inner)
    • 2. mesocarp (middle)
    • 3. exocarp (outer)
Card Set
PL SC 221
Plant Science 221 Flash Cards
Show Answers