Locomotion - Joints and tendons

Question 1

What is articular (hyaline) cartilage?

Answer 1

Cartilage that is hyaline (transparent), found in joints on the articular surface of bones.

Question 2

Does cartilage have a nervous or vascular supply?

Answer 2

No.

Question 3

Which is the most common type of joint in mammals?

Answer 3

Synovial joints.

Question 4

What is a joint?

Answer 4

(A.k.a. articulations) they are strong connections that join the bones, teeth, and cartilage of the body to one another.

Question 5

What is a synovial joint?

Answer 5

A joint containing a joint cavity filled with synovial fluid that is surrounded by a synovial membrane and a fibrous joint capsule.

Question 6

Where is synovial fluid secreted from?

Answer 6

The synovial membrane.

Question 7

What colour is synovial fluid?

Answer 7

Clear/straw coloured.

Question 8

What 3 roles does synovial fluid play in synovial joints?

Answer 8

Provides lubrication, absorbs shock, provides nutrient and waste transportation.

Question 9

What is a meniscus?

Answer 9

A crescent-shaped/’C’ shaped fibrocartilaginous structure that provides a surface for articulation.

Question 10

What function do the menisci in the knee (patellar joint) fulfill?

Answer 10

The menisci redistribute pressure about the joint surfaces during articulation by their ability to move and hence they can cushion blows. They also contribute to the lubrication and nourishment of the joint.

Question 11

What are the full names for the two menisci in the knee?

Answer 11

Medial meniscus and lateral meniscus.

Question 12

What is a bursae?

Answer 12

A fluid filled ‘cushion’, found in most joints in the body, that rests between bones and tendons and/or muscles around a joint. This helps to reduce friction between the structures.

Question 13

What is a tendon sheath?

Answer 13

A protective structure around a tendon. It allows for the smooth gliding of the tendon over structures that would otherwise likely cause friction and damage.

Question 14

What two layers are in a tendon sheath?

Answer 14

A synovial sheath and fibrous tendon sheath.

Question 15

What is a synsarcosis joint?

Answer 15

A joint where the attachments form from muscle only.

Question 16

Give an example of a synsarcosis joint.

Answer 16

Shoulder (Scapula) joint.

Question 17

What is a fibrous joint?

Answer 17

Usually a fully fixed or immovable joint, where the bones are connected with dense connective tissue. (There is an exception.)

Question 18

Fibrous joint - suture example

Answer 18

A joint where the bones gradually fuse together, such as the bones of the skull during early childhood.

Question 19

What 3 types of fibrous joint are there?

Answer 19

Sutures, Syndesmoses, Gomphosis

Question 20

Fibrous joint - syndesmoses example

Answer 20

A slightly movable (amphiarthrodial) joint found between some long bones of the body such as the radius and ulna.

Question 21

Fibrous joint - gomphosis example

Answer 21

A joint between the root of a tooth and the sockets in the maxilla or mandible.

Question 22

What is a cartilaginous joint?

Answer 22

They are connected entirely by cartilage (fibrocartilage or hyaline). They allow more movement between bones than a fibrous joint but less than the highly mobile synovial joint.

Question 23

Give an example of a cartilaginous joint.

Answer 23

Intervertebral disks, sternocostal joints.

Question 24

What are the 6 possible directions something can move?

Answer 24

1. Up/down
2. Left/right
3. Forward/backward
4. Tilting forward/backward (pitching)
5. Turning left/right (yawing)
6. Tilting side to side (rolling)

Question 25

Which joint gives rise to linear (translational) movement?

Answer 25

Planar joints.

Question 26

Which 2 joints give rise to uniaxial rotation?

Answer 26

Pivot and hinge joints.

Question 27

What is a planar joint?

Answer 27

Two flat surfaces glide over each other, eg some carpus/tarsus joints.

Question 28

What is a pivot joint?

Answer 28

A ‘peg in hole’ joint that allows them to rotate (uniaxial) about each other, eg radius and ulna.

Question 29

What is a hinge joint?

Answer 29

A convex-concave joint that allows pendulum motion (uniaxial), eg elbow (humeroulnar) joint

Question 30

List the 3 rotational biaxial types of joint.

Answer 30

Condyloid, Ellipsoid, Saddle.

Question 31

What is a condylar (condyloid) joint?

Answer 31

Two knuckle-shaped processes that sit in corresponding concaved grooves. It allows some side to side rotational movement as well as mainly pitching (biaxial), eg femoro-tibial (stifle) joint.

Question 32

What is a ellipsoid joint?

Answer 32

A semispherical (ovid) convex surface that sits in a corresponding concave cavity. It allows pitching and rolling of the joint (biaxial), eg radiocarpal joint.

Question 33

What is a saddle joint?

Answer 33

A convex surface and a concave surface at right angles to each other (see images). Allows biaxial movement, eg DIP joint of dog.

Question 34

What is the only multiaxial joint in the body?

Answer 34

Ball and socket hip joint.

Question 35

What is a ball and socket joint?

Answer 35

Joint that allows rotation in all planes although the degree of rotation may be limited, eg hip joint.

Question 36

What is flexion?

Answer 36

When the flexor aspect (angle) gets smaller.

Question 37

What is extension?

Answer 37

When the flexor aspect (angle) gets bigger.

Question 38

Give 2 ways that an animal can store energy during locomotion.

Answer 38

Tendon springs, flexible spine.