Fossil Morphology (Chapter 6)

Question 1

plane of axis of symmetry

Answer 1

plane (axis) that passes through the center of the object & divides into sides of mirror image

Question 2

heteromorphic

Answer 2

having many or multiple shape

e.g. Scaphites whitfield

Question 3

mirror image

Answer 3

something that is identical in form but its structure is reversed with reference to axis or plane

Question 4

bilateral

Answer 4

characteristic of being divisible into symmetrical halves on either side of a plane

Question 5

radial

Answer 5

symmetry around a center axis many rays radiating from center

Question 6

asymmetrical

Answer 6

lack of symmetry or equivalent parts of fossil

Question 7

planispiral

Answer 7

rotation around an axis that has bilateral plane of symmetry

• ex: ammonites
  
  • flat side - shows spiral symmetry
  • turn 90° - shows mirrored halves

Question 8

spiral

Answer 8

when tiers revolve around an axis

Question 9

pentagonal

Answer 9

organsims with 5 points of radial symmetry unique to phylum Echinodermata