### animal tissue | glia:

Microglia
* are a subcomponent of the immune system located in the brains that respond to injury
  - macrophages that become phagocytic upon injury to nervous system
  - of mesodermal origin rather than being true neuroglia
  - the smallest of the glial cells
* arise from macrophages and remove debris after cell injury or death.
* have phagocytic functions, scouring up dead cells and cleaning up debris
  - functions,scouring up dead cells and cleaning up debris
  - small, elongated nuclei without visible cytoplasm

Graft
* are stems cut from the parent plant and fused with rootstock from a different plant
  - susceptible to infection, resorption, displacement, and extrusion
  - visible when hair is parted through transplant area or when hair is disturbed
* can be powerful sculpting tools in reshaping the nose.
* differ by size and shape.
* is animal tissue
  - attachment
* often fail, resulting in complications that can leave patients blind and visually disabled.

### animal tissue | graft:

Bone graft
* Some bone grafts take longer to fuse for unknown reasons.
* require a source of blood supply which is the alveolar bone lining the defect.
* taken from someone else is called allograft.

### animal tissue | mucosa:

Hymen
* Some hymens have one hole, others have several
  - tear naturally in childhood, some during puberty
* are epitheliums
  - mucous membranes
  - often different from person to person
  - part of vaginas
* come in various shapes and designs
  - sizes and shapes, and, for most women, the hymen stretches easily
  - widely varying sizes and shapes

Pterygium
* is more common in hot, dry climates.
* thickening of the membrane that covers the eyeball.
* wing-like fibrovascular membrane usually on the side of the cornea towards the nose.

Squamous mucosa
* lacks any maturation and has no clear basal layer.
* shows no maturation except at the very top.

### animal tissue | mucous body part:

Membrane
* A mucous membrane is animal tissue
* Most mucous membranes come into contact.
* Most mucous membranes provide barriers
  - mechanical barriers
  - secrete digestive enzymes
* Mucous membrane covers the skeletal muscle and protects the body from microbes and pathogens
  - has receptors cells that absorb airborne chemical molecules
  - lacks the heavily keratinized layer of the outside skin
  - membranes appear icteric
* Mucous membranes are a potential route of entry into the body for bloodborne pathogens
  - all dry
  - also receptive to essential oils
  - an important primary body defense
  - body parts
  - found inside the rectum, vagina, penis, and mouth
  - moist and pink
* Mucous membranes are pink and moist
  - slightly moist
  - present in the anus, vagina, and throat
  - very dry
  - can become dark and congested
  - line the vagina, rectum, urethra, and the mouth
* Mucous membranes pink without discharge, hypertrophy, polyps, or other lesions
  - inflammation or lesions
* Mucous membranes produce lipozymes which break down the capsule around bacteria
  - sticky mucous to trap microorganisms
  - protect internal organs that are connected with the outside of the body
* Mucous membranes provide a barrier at body openings
* Mucous membranes secrete a mucus, viscid, gummy secretion, analogous to vegetable mucilage
* Some mucous membranes absorb nutrients.
* Some mucous membranes have layers
  - surface layers
  - lead to death

Nerve tissue
* has the ability to generate and conduct electrical signals in the body.
* includes the brain, spinal cord, and nerves.
  - composed of nerve cells, or neurons, bunched together to make a nerve
  - distributed throughout the body in a complex integrated communications network
  - the most pressure sensitive tissue in the body
* makes up the central nervous system and the peripheral nervous system.