Presentation on theme: "Freshwater Phytoplankton Key for the Northeast By: Rachael Brown, Sonya Carlson, and Diana Jackson Under the guidance of Dr. Alan Baker NEXT."— Presentation transcript:
Freshwater Phytoplankton Key for the Northeast By: Rachael Brown, Sonya Carlson, and Diana Jackson Under the guidance of Dr. Alan Baker NEXT
Introduction: This photographic key is intended to aid in identification of freshwater algae to the Genus level. Proceed through this key by clicking on the picture that most resembles your organism. Buttons to know: Home: Go to the beginning page at any time Back: Go to the last page viewed Forward: Go to the next page in the key To Start Key Click Here START
Cells with definite chloroplasts and nuclei, not blue-green in color Cells without definite chloroplasts and nuclei, blue-green in color
Vegetative cells usually grass-green in color and with a definite cell wall Vegetative cells not grass-green
Vegetative cells yellowish to brown with a glass-like silica wall of two overlapping halves Vegetative cells yellow-green with a cell wall
Class: Cyanophyceae Common Name: Cyanobacteria, blue-greens Continue to Genus
Rectangular Is the general contour of the specimen: Elongate strands of cellsOblong, Circular, or Globular Sperm shaped Note: A filament is a strand of cells arranged end to end
Are the filaments: Unbranched Branched Elongate filaments of cells
Filaments are found alone Unbranched: Filaments form together in parallel colonies (rafts)
Head has thin membrane Head has thick wavy membrane Sperm-Shaped
Filaments are joined at one end Filaments are parallel and are not joined together at any end
Filaments have elongate cells arranged end to end Filaments have horizontal cells that are stacked on top of each other
Filaments Found Alone Cells are round and are arranged in long filaments (like strands of pearls) Elongate unicells are found on a substrate unicells
Cell shape is rectangular Cell shape is oblong
Filaments are spaced apart from each other Filaments are lumped together
Option A: Oblong Cells float freely apart from each other Cells join in even numbers and have a clear membrane around them
Option B: Circular Cells are free floating with thin clear membranes Cells are congregated and encased in a round membrane
Encased Cells Cells are encased by a clear membrane Cells are encased in a thick green membrane
Order: Bacillariophyceae Common Name:Diatoms Continue to Genus
Is the shape of the organism rectangular? Is the shape of the organism circular or oval? Does organism have stalks?
Are there many rectangles joined together? Are the rectangles separate from each other?
Do the rectangles make a line or stairstep formation? Do the rectangles form a star? Do the rectangles form a box?
Width (W) of individual cells is 1/10 of the length (L) W L W L Width (W) of individual cells is 1/5 of the length (L)
Are there many small circles within the cells? Is the end of the cell a long spike or is there a few large circles within the cells?
Is the middle of the cell wider than either end? Is the end of the cell opposite of the stalk the widest section?
Are there smaller circles within the large circle? Are there lines around the edge of the circle? Is the shape of the organism oval?
Is the cell extremely long and skinny with the length (L) more than 15 times as much the width (W)?
Are the ends of the cell pointed (p) or rounded (r) )? Are the ends of the cell curved (c)? Are the ends of the cell flat (f)?
Is the cell the same width in the middle as it is nearer to the ends? (a is equal to b) Is the cell the wider in the middle than it is nearer to the ends? (a is larger than b)
Is the edge of the oval smooth? Does the edge of the oval have a distinct bump? Bump Smooth
Is there a distinct line down the length of the cell? Distinct Line Is no distinct line visible in the center of the cell?
Is the center area of the middle line is wider than the ends of the middle line with a distinct break in the center? Is the middle line even in width with a distinct break in the center? Is the middle line complete with no distinct break in the center?
Is the cell long and skinny with the length (L) more than 5 times as much the width (W)? Is the cell short with the length (L) less than 5 times as much the width (W)?
Are there distinct parallel lines extending from the middle of the cell to the edge? Is the interior of the cell a homogenous color without lines? Lines
Are the ends distinctly pointed? Are the ends distinctly rounded?
COLONIES (GROUPS OF CELLS) FILAMENTS (LINEARLY) CELLS ARE ARRANGED IN… SINGLE CELLS Class: Chlorophycae
COLONIES ARE… FLAT (2-D)SPHERICAL (3-D)
CELLS IN FILAMENTS HAVE… ONE CHLOROPLAST TWO CHLOROPLASTS MANY CHLOROPLASTS
SINGLE CELLS ARE… UNICELLULARHEMISPHERES
INDIVIDUAL CELL SHAPE IS… SPHERICAL OR ELLIPTICAL LONG OR ROD SHAPED SPIKEY
COLONIES HAVE… TIGHTLY PACKED CELLS SPACE BETWEEN CELLS