The Skeletal System (Axial) Pt. 2 Flashcards
How many vertebral bones exist in the spine during fetal development?
During fetal development, the spine consists of 33 separate bones called vertebrae
What are the separate bones of the spine called?
Vertebrae
How many of the 33 (fetal) vertebrae will fuse into composite bones?
Nine of these vertebrae will fuse forming two composite bones
What are the two composite bones that are formed from the fusing of 33 (fetal) vertebrae into nine bones? (2)
- Sacrum
- Coccyx
What do the sacrum and coccyx construct?
- Construct the inferior portion of the vertebral column
How many single bones exist in the vertebrae?
24 single bones
What are the first seven vertebrae called?
Cervical vertebrae
How many vertebrae are in the cervical vertebrae?
Seven
What are the next twelve vertebrae called?
Thoracic vertebrae
How many vertebrae are in the thoracic vertebrae?
Twelve
What are the last five vertebrae called?
Lumbar vertebrae
How many vertebrae are in the lumbar vertebrae?
Five
What vertebrae support the lower back?
Lumbar vertebrae
How should the vertebrae be remembered?
A good way to help remember thee vertebrae numbers might be to identify them with common meal times, 7 a.m., 12 p.m., and 5 p.m.
What is the order of the vertebrae? (5)
- 7 Cervical vertebrae
- 12 Thoracic vertebrae
- 5 Lumbar vertebrae
- Sacrum
- Coccyx
What are intervertebral discs?
Pads of flexible fibrocartilage which separate the single vertebrae
What does fibrocartilage do?
Separates the single vertebrae
What is the shape of the vertebral column?
The vertebral column is “S” shaped
What do the discs and the “s” shaped column prevent? When do they prevent it? (2)
- The discs along with the “s” shaped structure of the vertebral column work together to prevent shock to the head
- When walking and running
What do the “s” shaped column and vertebral column make up?
They also make the body trunk
What is the body of the vertebrae called?
Centrum
What are the features of the body or centrum of the individual vertebrae? Where does the weight-bearing part of the vertebrae face in the vertebral column? (2)
- Disc like
- Weight-bearing part of the vertebrae facing anteriorly in the vertebral column
What is the vertebral arch?
Arch formed from the joining of all posterior extentions
What forms the vertebral body? (2)
- laminae
- pedicles
What is the vertebral foramen?
Canal through which the spinal cord passes
What are the transverse processes?
Two lateral projections from the vertebral arch
What are the seven cervical vertebrae identified as?
C1 to C7
What do the seven cervical vertebrae form?
For the neck region of the spine
What is the C1 vertebrae called?
What is the C2 vertebrae called? (2)
- Atlas (C1)
- Axis (C2)
What does the atlas receive at the skull?
Receives the occipital condyles of the skull
What does the atlas allow us to do?What doesn’t the atlas have? (2)
- Allows us to nod yes
- Does not have a centrum
What does the axis act as?
Acts a a pivot for the rotation of the atlas and skull
What are the 12 thoracic vertebrae identified with? What describes them? (2)
- Identified as T1 to T12
- They are all typical
What are the thoracic vertebrae larger than?
Larger than the cervical vertebrae
What is the body somewhat shaped as?
Somewhat heart-shaped
What does the thoracic cavity have on each side?
Has two coastal clemifacets (articulating surfaces) on each side
What do the thoracic vertebrae receive?
Receive the heads of the ribs
What are the five lumbar vertebrae identified as?
Identified as L1 to L5
Description of lumbar vertebrae? (4)
- They have massive block-like bodies
- Short
- Hatchet-shaped spinous processes
- Look like a moose head from the lateral aspect
What are the alae? Where do they articulate and what do they form? (2)
- Wing-like in shape
- Articulates laterally with the hip bones, forming the sacroiliac joints
What does the sacrum form?
The posterior wall of the pelvis
What is the sacral canal?
The vertebral canal continuing inside the sacrum
What is the coccyx formed from?
Formed from the fusion of three to five tiny, irregularly shaped vertebrae
What is the coccyx a remnant of?
Is the human “tailbone”, a remnant of the tail that other vertebrae animals have
What is another name for sternum?
Breastbone
What is the sternum (breastbone)? (first 2)
- A typical flat bone
- Result of the fusion of three bones:
1. The manubrium
2. The body
3. The xiphoid process
What are the three bones that fuse to create the sternum? (3)
- the manubrium
- the body
- the xiphoid process
What pairs of ribs are the sternum attached to?
the first several pairs
What is the jugular notch?
concave upper border of manubrium
What can be done to the jugular notch easily?
can be palpated (examined by touch) easily
What are the true ribs?
first seven pairs
In what way do the true ribs attach to the sternum and by what? (2)
- attach directly to the sternum
- by costal cartilage
What are false ribs?
next five pairs
In what two ways false ribs attached to the sternum? (2)
- either attach indirectly to the sternum
- or are not attached to the sternum
What are floating ribs? What do they not attach to?
The last two pairs of false ribs that do not attach to the sternum
What are the intercostal spaces between the ribs filled with? What does that filling aid with?
Are filled with intercostal muscles that aid in breathing
