### shape | node:

Nodule
* All nodules seen on chest x-ray are cancerous.
* Many nodules are of similar size.
* actively fixing nitrogen for the plant are pink or red inside.
* affect the whole skin, the subcutaneous tissue and sometimes the musculature.
* are a dense mass of fibroblasts and collagen encircled by small vessels
  - aggregates of hemocytes that entrap invading microbes
  - benign growths on the vocal folds that usually result from vocal abuse or misuse
  - deeper and more substantive than papules
  - diseases
  - firm or hard and cold and painful
  - growths that form under the skin
  - larger than oolitic forms
  - rare
  - responsilble for nitrogen fixation
  - structures on plants where nitrogen fixation is done by symbiotic bacteria
  - the most severe form of acne lesion
  - typically bilateral
  - very apparent on carefully dug soybeans
* burst and ooze serum, later hardening to form scabs.
* can form in lungs surrounding spherules.
* consist mainly of collagen fibers surrounding one to several adult worms.
* develop on tender tissue of hair roots rather than corky tissue of older roots.
* grow around the root, forming a collar-like structure.
* have to maintain just the right amount of oxygen.
* leave scars.
* occur when the control of cell growth within the nodule is abnormal.
* seem to easily form around objects.
* sometimes do show stress - normally on the very sm all nodules.
* vary from a few millimeters to a few centimeters.

### shape | node | nodule:

Active nodule
* appear pink to the naked eye, indicating active hemoglobin.
* are pink to an almost blood red.
* look pink when broken open.

Cold nodule
* Most cold nodules are benign.
* are more likely to be malignant.
* demonstrate absence of activity.

### shape | node | nodule:

Geode
* Most geodes are round rocks that are plain on the outside
  - typically hollow whereas others are completely filled with massive, banded quartz
* Some geodes are formed out of molten lava rocks.
* are abundant in the area and are most easily found in creek beds
  - common in some areas and people pan for gold and gems in area streams
  - found in southeast Iowa and are the official state rock
  - hollow spheres in limestone
  - natural phenomena formed out of millions of years of geological evolution
  - partly hollow, globe shaped bodies found in some limestones and locally in other rocks
* are round rocks containing a cavity that is lined with rock crystals
  - stones, usually hollow filled with crystals or layers of agate
  - unique forms of nature, and like fingerprints, no two are exactly alike
* can also form in gas formed pockets in cooling volcanic ash beds and lavas.
* exhibit a wide range of sizes from inches in diameter to several feet.
* have a hollow interior usually filled with crystals of smoky quartz, quartz and amethyst.
* help to initiate astral travel, and assist in the pursuits of mathematics.
* often start as large bubbles in lava that are frozen in when lava hardens.
* usually form in one of two environments - either volcanic or sedimentary.

Lymphatic nodule
* Many lymphatic nodules are present, distinguish between primary and secondary nodules.
* Most lymphatic nodules are small and solitary.
* are the building units of larger lymphatic organs.

Root nodule
* are perennial and increase in size as the tree continues to grow.
* form when a type of bacterium, rhizobium, infects the plant's roots.

Subcutaneous nodule
* are firm, painless lesions that occur over bony surfaces just under the skin.
* represent cysticerci in the skin.

Sentinel node
* are a limited set of lymph nodes to which cancer is most likely to spread first.
* contains metastatic breast cancer.

Square node
* are a special case of rectangular that require that the length of the vectors be equal.
* have unexplored neighbors in the graph.

Organic shape
* look like things from nature.
* tend to be soft, curvilinear and irregular.