Week 30 / Muscle, Joints & Bones -2

Question 1

What are the three parts of the axial skeleton?

Answer 1

The axial skeleton consists of:

Skull
Vertebral column
Bony thorax

Question 2

What are the functions of the axial skeleton? [5]

Answer 2

Answer:

-Supports and protects organs in the cranial, spinal, and ventral body cavities.

Provides muscle attachment for:

-Adjusting head, neck, and trunk positions.
-Performing respiratory movements.
-Stabilizing or positioning the appendicular skeleton.

-Strong joints with limited movement, reinforced by ligaments.

Question 3

Question: What are the two sets of bones in the skull?

Answer 3

Answer: The skull consists of:

Cranium
Facial bones

Question 4

Question: How are the bones of the skull connected?
[except for?]

Answer 4

Answer: The bones are joined by sutures, except for the mandible, which is attached by a freely movable joint.

Question 5

Question: What is the function of the skull?

Answer 5

Answer: The skull protects the brain and guards the entrances to the digestive and respiratory systems.

Question 6

Question: How many bones are in the skull, and how are they categorized?

Answer 6

Answer: The skull contains 22 bones:

8 cranial bones (form the braincase)
14 facial bones

Question 7

Question: What additional bones are associated with the skull?

Answer 7

Answer: 7 additional bones:

6 auditory ossicles (located in the temporal bones)

1 hyoid bone (connected to the temporal bones by ligaments)

Question 8

Question: What are the bones of the cranium and their locations? [5]

Question: What are the smallest bones in the body, and where are they located?

Answer 8

Answer:

Occipital – Back of the skull
Parietal – Top and most of the sides
Frontal – Anterior (forehead)
Temporal – Lower sides of the skull
Sphenoid & Ethmoid – Form the floor of the cranium

Answer: The ear ossicles (in the middle ear) are the smallest bones:

Malleus
Incus
Stapes

Question 9

Question: What are the main bones of the face and their functions? [8]

Answer 9

Answer:

Maxillary bone – Forms the upper jawbone

Mandible – Forms the lower jawbone, the only freely movable skull bone

Nasal bones – Fuse to form the bridge of the nose

Inferior nasal conchae – Articulates with multiple bones and creates turbulence in airflow through the nasal cavity

Palatine bone – Forms the anterior portion of the palate

Lacrimal bone – Smallest facial bone, articulates with the frontal, maxillary, and ethmoid bones

Vomer – Thin bone that divides the nasal cavity

Zygomatic bone – Forms the prominence of the cheeks

Question 10

Question: What are the unique features of the skull?

Answer 10

Answer:

Sutures – Immovable joints between skull bones:
Coronal, Sagittal, Lambdoid, Squamous

Paranasal sinuses – Air-filled cavities located in bones near the nasal cavity

Fontanels – Soft spots in the fetal skull that:
Allow deformation during birth
Calcify over time to form sutures

Question 11

Question: What are the paranasal sinuses, and where are they located?

Answer 11

Answer: Paranasal sinuses are hollow portions of bones surrounding the nasal cavity.

Question 12

Question: What are the functions of the paranasal sinuses? [3]

Answer 12

Answer:

Lighten the skull
Produce mucus to moisten and clean the air
Enhance voice resonance and amplification

Question 13

Question: What are fontanelles in the fetal skull? what is their function?

Answer 13

Answer: Fontanelles are fibrous membranes connecting cranial bones in the fetal skull.

Question 14

Question: What are the functions of fontanelles?
[1]
what do they convert to 24 months after birth

Answer 14

Answer:

Allow brain growth
Convert to bone within 24 months after birth

Question 15

Question: What is the function of the hyoid bone?

Answer 15

Answer: The hyoid bone supports the larynx and serves as an attachment site for muscles of the larynx, pharynx, and tongue.

Question 16

Question: What are the orbits, and what is their function? [3]

Answer 16

Answer: The orbits are bony cavities that:

Firmly encase the eyes

Cushion the eyes with fatty tissue

House the muscles that move the eyes and the lacrimal glands that produce tears

Question 17

Question: What are the specific functions of the parts of the hyoid bone?

Answer 17

Answer:

Body of the hyoid – Attachment site for muscles of the larynx, tongue, and pharynx.

Greater horns – Support the larynx and attach to muscles that move the tongue.

Lesser horns – Attach to the stylohyoid ligaments, supporting the larynx.

Question 18

Question: How many bones form the walls of the orbit?

Answer 18

✅ Answer: The walls of the orbit are formed by seven bones.

Question 19

Question: What are the functions of the vertebral column? [3]

Answer 19

Answer:

Encloses the spinal cord

Supports the head

Serves as a point of attachment for muscles of the back, ribs, and pelvic girdle

Question 20

Question: What are the regions of the vertebral column, listed from superior to inferior?

Answer 20

Answer:

7 cervical
12 thoracic
5 lumbar
1 sacrum
1 coccyx

Question 21

Question: What are the four normal curves in the vertebral column?

Answer 21

Answer:

Cervical and lumbar curves – Convex (bulge anteriorly)
Thoracic and sacral curves – Concave (bulge posteriorly)

Question 22

🧠 Question: What are the functions of the curves in the vertebral column? [3]

Answer 22

✅ Answer: The curves:

Increase strength
Help with balance
Absorb shocks

Question 23

🧠 Question: What is the structure of a vertebra?

Answer 23

✅ Answer:

Body – Disc-shaped anterior portion
Vertebral arch – Located posteriorly from the body, forms a hole called the vertebral foramen

Question 24

🧠 Question: What are the seven processes that extend from the vertebral arch?

Answer 24

✅ Answer:

Transverse process – Extends laterally on each side
Spinous process – Extends dorsally
Superior and inferior articular processes (two of each) – Form joints with adjacent vertebrae

Question 25

🧠 Question: What is the structure of the cervical vertebrae? [3]

Answer 25

✅ Answer: Cervical vertebrae (C1-C7): Spinous process is often bifid Transverse foramina on the transverse processes

Question 26

🧠 Question: What is special about C1 (Atlas)?, [3]

Answer 26

✅ Answer: C1 (Atlas): Articulates with the head Specialized to support the head Lacks a body and spinous process

Question 27

🧠 Question: What is special about C2 (Axis)?[2]

Answer 27

✅ Answer: C2 (Axis): Has a body and spinous process Contains the dens (tooth-like projection) that creates a pivot for head rotation

Question 28

🧠 Question: What is the structure of the thoracic vertebrae? [3]

Answer 28

✅ Answer: Thoracic vertebrae (T1-T12): Larger than cervical vertebrae Have facets for articulating with the ribs

Question 29

🧠 Question: What is the structure of the lumbar vertebrae? [3]

Answer 29

✅ Answer: Lumbar vertebrae (L1-L5): Largest and strongest vertebrae Short and thick spinous processes

Question 30

🧠 Question: What is the structure and function of the sacrum?

Answer 30

✅ Answer: Sacrum (S1-S5): Fused into one unit Forms the foundation for the pelvic girdle Contains sacral foramina for nerves and blood vessels

Question 31

🧠 Question: What is the structure of the coccyx?

Answer 31

✅ Answer: Coccyx: 4 coccygeal vertebrae fused into 1

Question 32

🧠 Question 1: What is the average length of the adult vertebral column? 🧠 Question 2: How much of the vertebral column's length is accounted for by intervertebral discs? 🧠 Question 3: How does a person’s height change when in bed? 🧠 Question 4: What happens to the intervertebral discs during the day and at night?

Answer 32

✅ Answer: The adult vertebral column averages 71 cm (28 inches) in length. ✅ Answer: Intervertebral discs account for about one-quarter of the vertebral column's length. ✅ Answer: A person is about 1% shorter when in bed due to the compression of the vertebral column during the day. ✅ Answer: During the day, compression squeezes water out of the discs. At night, when compression is removed, the discs absorb water.

Question 33

🧠 Question: What are the functions of the vertebral column?

Answer 33

✅ Answer: Provides bony protection for the spinal cord Allows access to the spinal cord for spinal nerves, blood vessels, and lymph vessels Enables movement through individual vertebrae and intervertebral discs Provides support for the skull Acts as a shock absorber protecting the brain Serves as an attachment for the ribs, shoulder girdle, upper limbs, pelvic girdle, and lower limbs.

Question 34

🧠 Question: What are the causes of abnormal spinal curvatures?

Answer 34

✅ Answer: Abnormal spinal curvatures can result from: Disease, Paralysis of trunk muscles, Poor posture, Pregnancy, Congenital defects

Question 35

🧠 Question: What is scoliosis, and how does it occur?

Answer 35

✅ Answer: Scoliosis is an abnormal lateral curvature of the spine, most commonly in the thoracic region. It is often a developmental abnormality in which the body and arch fail to develop on one side of the vertebrae. It is more common in adolescent girls.

Question 36

🧠 Question: What is kyphosis, and what causes it?

Answer 36

✅ Answer: Kyphosis (hunchback) is an exaggerated thoracic curvature. It is usually caused by osteoporosis, but can also result from osteomalacia, spinal tuberculosis, or physical activities like wrestling or weightlifting in young boys.

Question 37

🧠 Question: What is lordosis, and what causes it?

Answer 37

✅ Answer: Lordosis (swayback) is an exaggerated lumbar curvature. It is commonly caused by pregnancy or obesity.

Question 38

🧠 Question: What makes up the thoracic cage?[4]

Answer 38

✅ Answer: The thoracic cage consists of: Sternum Costal cartilages Ribs Bodies of vertebrae T1-T12

Question 39

🧠 Question: How are the ribs categorized, and how do they articulate with the sternum?

Answer 39

✅ Answer: True ribs (1-7): Directly articulate with the sternum via costal cartilages. False ribs (8-12): Do not articulate directly with the sternum but connect through costal cartilages.

Question 39

🧠 Question: What are the three portions of the sternum?

Answer 39

✅ Answer: The sternum is formed by three portions, which fuse by around age 25: Manubrium Body Xiphoid process

Question 40

🧠 Question: How are joints formed between the ribs and vertebrae?

Answer 40

✅ Answer: Two joints are formed between the facets on the head of the rib and the facets on the bodies of two vertebrae. Ten ribs form joints between the tubercle of the rib and the transverse process of the lower vertebra.

Question 40

🧠 Question: What feature does the inferior surface of the rib have, and what does it contain?

Answer 40

✅ Answer: The inferior surface of the rib is deeply grooved, providing a channel for the intercostal nerves and blood vessels.