Connective Tissues

Question 1

Fibroblasts

Answer 1

A large flat cell that secretes collagen, proteins, and fibers to maintain the framework (extracellular matrix and ground substance) of connective tissue in the body. (These are the usually the most numerous in connective tissues.)

Question 2

Macrophages

Answer 2

These cells have an irregular shape with short branching projections. They play a vital role in consuming cellular debris and bacteria in a process called phagocytosis.

Question 3

Plasma cells

Answer 3

Plasma cells secrete antibodies (proteins that attack or neutralize foreign substance in the body). They are an important part of the immune system. Mainly found in connective tissues. Also abundant in salivary glands, lymph nodes, the spleen, and bone marrow. (type of white blood cell)

Question 4

Mast cells

Answer 4

Abundant alongside the blood vessels that supply connective tissue. They produce histamine, a chemical that dilates small blood vessels as a part of an inflammatory response, the body’s reaction to injury or infection. They can also bind to, ingest, and kill bacteria.

Question 5

Adipocytes

Answer 5

Connective tissue cells that store triglycerides (fats). They are found deep to the skin and around organs such as the heart and kidneys.

Question 6

Leukocytes

Answer 6

Not normally found in significant numbers in connective tissue however, in response to certain conditions they migrate from blood into connective tissue. (white blood cells)

Question 7

Ground substance

Answer 7

the component of a connective tissue between the cells and fibers. The ground substance may be fluid, semifluid, gelatinous, or calcified. it supports cells, binds them together, stores water, and provides a medium of exchange of substances between the blood and cells.

Question 8

Cartilage

Answer 8

dense network of collagen fibers and elastic fibers firmly embedded in chondroitin sulfate (a gel-like component of the ground substance). Can endure more stress than loose connective tissues. It has no nerves or blood cells in its extracellular matrix.

Question 9

Chondrocytes

Answer 9

The only specialized cell type found in cartilage. They produce collagen and the extracellular matrix found in cartilage. They are only found in the lacunae in the extracellular matrix.

Question 10

Areolar connective tissue

Answer 10

(loose connective tissue) one of the most widely distributed connective tissues; consists of fibers (collagen, elastic, reticular) and several kinds of cells (fibroblasts, macrophages, plasma cells, adipocytes, mast cells, and a few white blood cells, embedded in in a semifluid ground substance.
Location: in and around nearly every body structure
Function: Strength, elasticity, support.

Question 11

Adipose connective tissue

Answer 11

(Loose connective tissue) has cells derived from fibroblasts that are specialized for storage of triglycerides (fats) as a large centrally located droplet. Cells fill up with a single, large, triglyceride droplet and cytoplasm and nucleus are pushed to the periphery of the cell. Most adipose tissue in adults is white adipose tissue (just described). Brown adipose tissue is darker due to higher blood supply and is found in fetus and infants (adults have a smaller amount).
Location: wherever areolar connective tissue is located.
Function: reduces heat loss through skin, serves as energy reserve, supports and protects organs.

Question 12

Blood

Answer 12

blood plasma and formed elements: red blood cells. white blood cells (leukocytes), platelets.
Location: within blood vessels (arteries, arterioles, capillaries, venules, veins.) within chambers of heart.
function: red blood cells: transport oxygen. and some carbon dioxide. White blood cells: carry on phagocytosis and mediate allergic reactions and immune system responses. platelets: essential for blood clotting.

Question 13

Bone

Answer 13

compact and spongey bone tissue.
location: both types of bones make up various parts of bones of the body.
Function: support, protection; houses blood-forming tissue; serves as lever that act with muscle tissue to enable movement.

Question 14

Collagen fibers

Answer 14

very strong and resist tensions, but are not stiff which allows tissue flexibility. Collagen fiber properties vary from tissue to tissue. They normally occur in parallel bundles. They are primarily made up of the protein collagen. (found in most types of connective tissues, especially bones, cartilage, tendons and ligaments.

Question 15

Elastic fibers

Answer 15

Smaller in diameter than collagen fibers, branch and join together to form a fibrous network within a connective tissue. Elastic fibers are strong but can be stretched to 150% of their relaxed length without breaking. They can also return to their natural state after being stretched a property known as elasticity. Plentiful in skin, blood vessel walls, and lung tissue.

Question 16

Reticular fibers

Answer 16

Consists of collagen arranged in fine bundles with a coating of glycoprotein, they provide support in the walls of blood vessels and form a network around the cells in some tissues such as areolar connective tissue, adipose tissue, nerve fibers, and smooth muscle tissue. They are much thinner than collagen fibers but also provide strength and support. These fibers also help form the basement membrane and are most populous in reticular connective tissue, which forms the supporting framework of many soft organs.

Question 17

Dense regular connective tissue

Answer 17

forms shiny, white extracellular matrix. Mainly made up of collagen fibers regularly arranged in bundles with fibroblasts in rows between them. Collagen fibers are not living, so damaged tendons and ligaments heal slowly.
Location: forms tendons, and most ligaments.
Function: provides strong attachment between various structures.

Question 18

Dense irregular connective tissue

Answer 18

Made up of collagen fibers, usually irregularly arranged with a few fibroblasts.
Location: occurs often in sheets.
function: provides tensile (pulling) strength in many directions.

Question 19

Hyaline cartilage

Answer 19

Appears in the body as a bluish, white, shiny substance.
Location: Most abundant cartilage in the body; at the ends of long bones, anterior ends of ribs, nose, parts of larynx, trachea, bronchi, bronchial tubes, embryonic and fetal skeleton.
Function: provides smooth surfaces for movement at joints, flexibility, and support; weakest type of cartilage and can be fractured.

Question 20

Elastic connective tissue

Answer 20

contains mainly elastic fibers with fibroblasts in between them.
Location: lung tissue, walls of elastic arteries, trachea, bronchial tubes, true vocal cords, some ligaments between vertebrae.
function: allows stretching of various organs, is strong and can recoil to original shape after being stretched. Elasticity is important to normal functioning of lung tissue and elastic arteries.

Question 21

Fibrocartilage

Answer 21

lacks perichondrium
function: support and joining structures together. strength and rigidity make it the strongest type of cartilage.
location: pubic symphysis, intervertebral discs, menisci of knee, portions of tendons that insert into cartilage.

Question 22

elastic cartilage

Answer 22

chondrocytes in a network of elastic fibers within a extracellular matrix.
Location: lid on top of larynx, part of external ear, eustachian tubes.
function: provides strength and elasticity: maintains shape of certain structures.