Skeleton and Muscles

Question 1

What are the functions of the skeleton?

Answer 1

Support
Protection
Movement
Manufacture of blood cells

Question 2

What does axial skeleton consist of ?

Answer 2

1. The Skull
2. The Spine-protects the spinal cord
3. The Rib cage

Question 3

What is the function of cartilage?

Answer 3

Cartilage acts as a shock absorber and protects the vertebrae.

Question 4

What does the skull have?

Answer 4

over 20 bones fused together

Question 5

What does the spine have?

Answer 5

33 bones called Vertebrae
top 24 vertebrae move slightly,are separated by discs of cartilage.
The bottom 9 vertebrae are fused and have no discs.

Question 6

What does the vertebrae column consist of?

Answer 6

Cervical (neck)-7
Thoracic (chest)-12
Lumbar (back)-5
Sacrum (hip)-5
Coccyx (tail)-4

Question 7

What does the ribcage have?

Answer 7

12 pairs of ribs(which are attached to the vertebrae of the spine) and the sternum (breast bone).
Top 7 ribs = true ribs ,they are attached to the sternum (breastbone)
Next 3 ribs = false ribs as they are attached to each other.

Question 8

What are true ribs?

Answer 8

Top 7 ribs = true ribs ,they are attached to the sternum (breastbone)

Question 9

What are false ribs?

Answer 9

Next 3 ribs = false ribs as they are attached to each other.

Question 10

What are floating ribs?

Answer 10

The bottom 2 ribs are called floating ribs as they are only attached to the spine at the back.

Question 11

What are the parts of the Appendicular Skeleton

Answer 11

Pectoral Girdle (shoulder girdle)
Pelvic Girdle
Cartilage

Question 12

What does the pectoral girdle consist of?

Answer 12

clavicle (collar bone)
the scapula (shoulder blade).
Each arm is attached to the shoulder and consists of the humerus, radius and ulna, carpels (wrist), metacarpels (hand) and phalanges (fingers).

Question 13

Describe the limb structure of the appendicular skeleton:

Answer 13

arms and legs have a similar design pattern. Each end in 5 phalanges (fingers or toes) and so are called pentadactyl limbs

Question 14

What does the pelvic girdle consist of?

Answer 14

2 hip bones attached to the sacrum (part of backbone).
Each leg is attached to the hip girdle and consists of the femur, patella (knee cap), tibia and fibula, tarsals (ankle), metatarsals (foot) and phalanges (toes).

Question 15

What is cartilage?

Answer 15

Jelly like protein (collagen) matrix with cells embedded in it.
Forms entire skeleton of embryo but is then replaced by bone.

Question 16

Where is cartilage found?

Answer 16

It is also found in rings around the trachea, in nose and ears and intervertebral discs. No blood vessels or nerves-it depends on materials diffusing through it to the cells that make it.

Question 17

What is compact bone?

Answer 17

Composed of bone cells (osteoblasts) embedded in a matrix of inorganic calcium salts and collagen..
Compact bone gives strength (calcium salts) and flexibility (collagen).
Mainly in the diaphysis of bone and forms layer around the ends of a bone.

Question 18

What is spongy bone?

Answer 18

Less dense than compact bone, contains spaces filled with red bone marrow. Spongy bone gives strength and rigidity to the skeleton.
Mainly in the epiphysis of bone.

Question 19

What is bone marrow?

Answer 19

Bone marrow is a soft, fatty substance found in

the medullary cavity and within spongy bone.

Question 20

What is red marrow?

Answer 20

Active marrow which makes blood components
and blood cells. Red marrow is confined to
spongy bone in adults.

Question 21

what is yellow marrow

Answer 21

Inactive fat-rich marrow in the medullary cavity of
bones in adults. Yellow marrow can convert to red bone
marrow if increased blood cell production is required.

Question 22

What are the stages of bone development?

Answer 22

. In the embryo cartilage begins to be replaced by bone at about 8weeks into pregnancy. Bone forming cells (osteoblasts) invade the cartilage, produce a flexible matrix of collagen and fill it with calcium salts (hard-gives strength). The osteoblasts become trapped in the matrix and become dormant (inactive).
2. There is a growth plate in bones made of cartilage, between the epiphysis and diaphysis of a bone.
This increases the length of a bone-cartilage is continually formed and turned into bone (ossified).
The growth plate ceases to function when the person becomes an adult.
Throughout a person’s life the skeleton is under constant renewal-the bone is dissolved and replaced. This happens at least 10 times throughout the life of a bone. Two types of bone cells are involved.

Question 23

What is a joint?

Answer 23

A joint is where two bones meet.

Question 24

What is an immovable joint(fixed or fused joints)?

Answer 24

e.g. skull, pelvic girdle and coccyx.

Question 25

What are slight movable joints?

Answer 25

E.g. the joints between vertebrae, which allow some movement of the backbone.

Question 26

What are freely movable joints(synovial joints)?

Answer 26

Ball and socket joint: e.g. shoulder and hip-allow for movement in all directions.
Hinge joint: e.g. elbow and knee-allow for movement in one direction only.

Question 27

what are the three types of muscle?

Answer 27

skeletal muscle
cardiac muscle
smooth muscle

Question 28

What is skeletal muscle?

Answer 28

Voluntary muscle attached to bone (biceps).

Under conscious control to move the body, contracts quickly and tires easily.

Question 29

What is the cardiac muscle?

Answer 29

Involuntary muscle, found in the heart, does not tire.

Question 30

What is smooth muscle?

Answer 30

Involuntary muscle found in blood vessels & digestive structures, (oesophagus, stomach, intestines-for peristalsis), uterus, bladder, iris. It is not under conscious control.

Question 31

What are antagonistic pairs?

Answer 31

An antagonistic pair is two muscles that have opposite effects to each other. (biceps contracts to pull the arm up and triceps contract to lower the arm)

Question 32

Arthritis

Answer 32

A disorder causing inflammation of a joint.
Cause: The cartilage in the synovial joint wears down over time The joint swells and becomes sore and stiff.

Prevention: Try to reduce damage to joints by using proper footwear and exercising by walking or swimming instead of running.

Treatment: Special exercises and physio to maintain strength, anti-inflammatory drugs to reduce inflammation. Surgery to replace the joint.

Question 33

What is bone development affected by?

Answer 33

Physical activity-stress from exercise stimulates osteoblasts which build up bone, making it thicker and stronger.

(ii) Growth Hormone-increases bone size
(iii) Sex hormones such as oestrogen and testosterone increase bone size, seen at puberty.
(iv) Parathyroid hormone

Question 34

What is the function of compact bone ?

Answer 34

Compact bone gives strength (calcium salts) and flexibility (collagen).

Question 35

What is the synovial joint made out of

Answer 35

Cartilage: Covers the end of the bones, reduces
friction and acts as a shock absorber.

Ligaments- Strong, fibrous slightly elastic tissues that
connect bone to bone.

Tendons –Strong flexible, inelastic fibres that
connect bone to muscle.

Synovial fluid-Secreted by synovial membranes,
lubricates the joint and reduces friction.

Question 36

what is the long shaft bone called?

Answer 36

diaphysis.

Question 37

What is the head of the bone called?

Answer 37

epiphysis

Question 38

What is the name of the membrane long bones are enclosed by?

Answer 38

Periosteum

Question 39

Osteoclasts

Answer 39

digest the bone that lines the medullary cavity. They deposit calcium into the blood vessels.Osteoclast alone would weaken and thin the bones.

Question 40

Osteoblasts

Answer 40

Osteoblasts: form new bone to replace the bone that is destroyed.