Connective Tissue Supports and Protects Flashcards
1
Q
What is the major function of connective tissue?
A
- connect tissues and organs
2
Q
characteristics of connective tissues?
A
- ## connective tissue cells are dispersed in a matrix
3
Q
matrix
A
- includes a large amount of extracellular material produced by connective tissue cells that are embedded in it
- plays major role in functioning of this tissue
- major componenet of matrix is: ground substance crisscrossed by protein fibers
- come in vast variety of forms (typically 3 characteristic components): cells, large amounts of amorphous ground substance, and protein fibers
- amount and structure of each component correlates with functino of tissue
4
Q
what is ground substance
A
- major component of matrix in connective cells
- usually fluid, but can also be mineralized and solid (as in bones)
5
Q
what are the functions of connective tissue?
A
- support and connect other tissues (connective tissue sheath that surrounds muscle cells –tendons attach muscle to bones –the skeleton that supports positions of the body)
- protection (fibrous capsules and bones protect delicate organs, skeletal system)
- specialized cells in connective tissue defend body from microorganisms
- transport of fluid, nutrients, waste and chemical messengers (ensured by specialized fluid connective
6
Q
where do connective tissues derive from?
A
- a mesodermal layer of the embryo
7
Q
what is the first connective tissue to develop?
A
- mesenchyme: stem cell line from which all connective tissues are later derived
- clusters are scattered throughout adult tissue and supply the cells needed for replacement and repair after a connective tissue injury
8
Q
what is the second type of embryonic connective tissue that forms?
A
- mucous connective tissue or whartons jelly
- form through the umbilical cord
- tissue is no longer present after birth leaving only scattered mesenchymal cells throughout the body
9
Q
What are the 3 broad categories of connective tissue
A
- connective tissue proper: includes loose connective tissue and dense connective tissue (both tissues have a variety of cell types and protein fibers suspended in viscous ground substance).
10
Q
dense connective tissue
A
- reinforced by bundles of fibers that provide tensile strength, elasticity, protection
11
Q
loose connective tissue
A
- fibers are loosely organized, leaving large spaces in between
12
Q
supportive connective tissue
A
- bone and cartilage
- provide structure and strength to the body and protect soft tissues
- few distinct cell types and densely packed fibers in a matrix characterize these tissues
- in bone: matrix is rigid and described as calcified because of deposited calcium salts
- ex: cartilage (hyaline, fibrocartliage, elastic), bone
13
Q
fluid connective tissue
A
- in lymph and blood, various specialized cells circulate in watery fluids contain salts, nutrients, and dissolved proteins
- ex: blood, lymph
14
Q
connective tissue proper examples
A
loose connective tissue
- areolar
- adipose
- reticular
dense connective tissue
- dense regular
- elastic
- dense-irregular
15
Q
Fibroblasts
A
- present in all connective tissue proper
- most abundant cell in connective tissue proper
- polysaccharides and proteins secreted by fibroblasts combine with extra-cellular fluids to produce a viscous ground substance that, with embedded fibrous proteins, forms an extracellular matrix
16
Q
fibrocyte
A
- less active form of fibroblast
- second most common cell type in connective tissue proper
17
Q
adipocytes
A
- cells that store lipids as droplets that fill most of cytoplasm
- two basic types: white and brown
- brown: store lipids as many droplets, have high metabolic activity
- white: store lipids as single large drop and are metabolically less active
- very effective at storing large amounts of fat
- number and type of adipocytes depend on tissue and location, vary among individuals in the population