Bone Tissue And Skeletal System

Question 1

Osteogenic Vells

Answer 1

Stem cells that develop from embryonic mesenchyme and then give rise to most other bone cell types

Question 2

Osteoblasts

Answer 2

Bone forming cells that synthesize the organic matter of the bone and promote it’s mineralization. This bone building activity is called osteogenesis

Question 3

Osteocytes

Answer 3

Former osteoblasts that have become imbedded in the matrix they deposited

Question 4

Osteoclasts

Answer 4

Bone dissolving cells on the bone surfaces. Their action is called osteolysis

Question 5

Bone Matrix

Answer 5

The Stony matter that surrounds the osteocytes and lacunae. 1/3 Organic and 2/3 inorganic material.

Question 6

Compact Bone

Answer 6

The hard outer layer of bones is composed ofcortical bone, which is also calledcompact boneas it is much denser than cancellous bone. It forms the hard exterior (cortex) of bones. The cortical bone gives bone its smooth, white, and solid appearance, and accounts for 80% of the total bone mass of an adult humanskeleton.It facilitates bone’s main functions—to support the whole body, to protect organs, to provideleversfor movement, and to store and release chemical elements, mainly calcium. It consists of multiple microscopic columns, each called anosteonor Haversian system. Each column is multiple layers ofosteoblastsandosteocytesaround a central canal called thehaversian canal.

Question 7

Spongy Bone

Answer 7

Cancellous bone, orspongy bone,also known astrabecular bone, is the internal tissue of the skeletal bone and is an open cellporousnetwork that follows the material properties ofbiofoams.Cancellous bone has a highersurface-area-to-volume ratiothan cortical bone and it is lessdense. This makes it weaker and more flexible. The greater surface area also makes it suitable for metabolic activities such as the exchange of calcium ions. Cancellous bone is typically found at the ends of long bones, near joints, and in the interior of vertebrae. Cancellous bone is highlyvascularand often contains redbone marrowwherehematopoiesis, the production of blood cells, occurs.

Question 8

Trabeculae

Answer 8

Atrabecula(pl:trabeculae, from Latin for ‘small beam’) is a small, often microscopic,tissueelement in the form of a smallbeam,strutor rod that supports or anchors a framework of parts within a body or organ.A trabecula generally has a mechanical function, and is usually composed of densecollagenoustissue (such as thetrabeculaof thespleen). It can be composed of other material such as muscle and bone

Question 9

Condyle

Answer 9

A rounded knob that articulates with another bone (occipital condyles of the skull)

Question 10

Facet

Answer 10

A smooth, flat, slightly concave or convex articular surface (articular facets of the vertebrae)

Question 11

Head

Answer 11

The prominent expanded end of a bone, sometimes rounded (head of the femur)

Question 12

Crest

Answer 12

A narrow ridge (iliac crest of the pelvis)

Question 13

Epicondyle

Answer 13

An expanded region proximal to a condyle (medial epicondyle of the femur)

Question 14

Line

Answer 14

A slightly raised, elongated ridge (nuchal lines of the skull)

Question 15

Process

Answer 15

Any bony prominence (mastoid process of the skull)

Question 16

Protuberance

Answer 16

A bony outgrowth or protruding part (mental protuberance of the chin)

Question 17

Ramus

Answer 17

A branch or arm (ramus of mandible)

Question 18

Spine

Answer 18

A sharp, slender, or narrow process (mental spines of the mandible)

Question 19

Trochanter

Answer 19

Two massive processes unique to the femur

Question 20

Tubercle

Answer 20

A small, rounded process (greater tubercle of the humerus)

Question 21

Tuberosity

Answer 21

A rough elevated surface (tibial tuberosity)

Question 22

Alveolus

Answer 22

A pit or socket (tooth socket)

Question 23

Fossa

Answer 23

A shallow, broad, or elongated basin (mandibular fossa)

Question 24

Fovea

Answer 24

A small pit (fovea capitis of the femur)

Question 25

Sulcus

Answer 25

A groove for a tendon, nerve, or blood vessel (intertubercular sulcus of the humerus)

Question 26

Canal

Answer 26

A tubular passage or tunnel in a bone (auditory canal of the skull)

Question 27

Fissure

Answer 27

A slit through a bone (orbital fissures behind the eye)

Question 28

Foramen

Answer 28

A hole through a bone, usually round (foramen magnum of the skull)

Question 29

Sinus

Answer 29

An air-filled space in a bone (frontal sinus of the forehead)

Question 30

Hyoid Bone

Answer 30

The hyoid is a floating bone found at the junction of the floor of the mouth and the neck. The hyoid may be anchored by mus- cles from the anterior, posterior, or inferior directions; it aids tongue movement and swallowing. The larynx and trachea are suspended from the hyoid by the thyrohyoid ligament.