Chapter 5 Flashcards
What are the functions of the
skeletal system
- Provide structure, support, protection, movement
- Explain the differences between compact
bone and spongy bone
- Compact Bone – hard, dense, smooth
- Spongy bone – lighter, sponge appearance
- Name the four main classifications of bone
according to shape.
- Long
- Short (cube shaped)
- Flat
- Irregular
- Name the areas of a long bone
Diaphysis - shaft
Epiphyses – ends of bone
Periosteum – external surface of bone
Articular cartilage - cushions joint
Epiphyseal plate - cartilage in children growing bones
- Describe the microscopic structure of compact bone
- Osteon (Haversian) system – entire circles running down the bone shaft (wooden rings, central canal, and blood vessels/nerves)
- Lamellae – outer wooden rings like a tree
- Interstitial Lamellae – Spaces in between the circles (bone matrix)
- Lacunae - depressions containing osteocytes (bone maintanence cell) look like bugs
- Central canal - centre hole where the blood vessels and nerves run though
Canaliculus - tunnels going from central canals to osteocytes
- Identify the names and shapes of significant bone markings.
- Bone markings – landmarks where muscles/ blood vessels/ nerves are
o Projections – stick out (T terms)
o Depressions – indentations (F Terms)
- Describe the cells involved in bone formation, growth, and remodeling
- Osteoblasts build new bone.
- Osteoclasts break down bone
- Epiphyseal Plates – allow growth and leave the epiphyseal line behind on the bone
- Describe the significance of epiphyseal plates in bone growth
- Epiphyseal plates (growth plates) – cartilage that will eventually turn into bone at the ends in childhood
o leaves behind the epiphyseal line
- Explain how appositional growth causes the bone to become thicker and stronger.
- Bones increase in diameter to become wider as well as longer when growing
- Describe the homeostatic regulation of blood calcium, including identifying the
receptor, control centre, and effector, and apply this knowledge
- Receptor: detect the calcium level in blood.
- Control Center: parathyroid glands (in the thyroid gland).
- Effector: When calcium levels are too low, they release a hormone called parathyroid hormone (PTH) to correct it. If blood calcium is too high, the thyroid gland releases calcitonin, and levels fall.
- Describe how calcitonin and parathyroid hormone maintain the homeostatic balance of blood calcium level, and apply this knowledge
- When calcium levels are low, PTH raises them by taking calcium from the bones and helping the body absorb more from food.
- When calcium levels are high, calcitonin lowers them by storing more calcium in the bones and reducing the amount of calcium absorbed.
- Together, PTH and calcitonin work like a balancing system to keep blood calcium levels within a healthy range.
- Distinguish between the axial and
appendicular skeletons.
- Axial skeleton along the longitudinal axis of the body
o It has 3 parts: skull, vertebral column, thoractic cage
o Green colored on diagram - Appendicular skeleton – bones of the limbs
o Shaded gold on diagram
o Include the pelvic girdle bones (hips) and pectoral girdle bones (shoulders and traps)
- Identify and describe the major bones of the skull (8)
- Frontal bone – forehead/ upper eye
- Parietal bone – top and back/ sides of head
- Occipital bone – base (connects spinal cord to brain)
- Temporal bone – ears
- Nasal – nose bridge
- Zygomatic - cheekbone
- Maxilla – upper jaw
- Mandible – lower jaw
- Describe the function and location of the hyoid bone.
- In the neck, no joint with other bones
- It is a moveable base for the tongue and attachment for neck muscles
- Describe the vertebral column and how many vertebrates do we have?
- The spine supports your weight, protects the spinal cord,
- It has 24 vertebrae total:
o Cervical vertebrae (7 vertebrae): Located in the neck.
o Thoracic vertebrae (12 vertebrae): Located in the upper and mid-back.
o Lumbar vertebrae (5 vertebrae): Located in the lower back.
2 Sacrum and coccyx fuse together at the bottom of the spine
- Describe the location, parts, and function of the thoracic cage
- The ribcage – made up of bones and cartilage
- Organs inside being protected are heart, lungs, major blood vessels
- Describe the location and parts of the sternum
- Sternum (breastbone) is a flat bone attached to the ribcage (thoracic cage) that fuses 3 bones:
o Manubrium
o Body
o Xiphoid process
- Identify and describe the bones of the shoulder girdle and describe its function
- Clavicle – two collarbones, stabilizes the shoulder by bracing the arm at your side
- Scapula - shoulder blades at back (our “wings), allows movement of arm in many directions
- Identify and describe the bones of the upper limb
- Arm – humerus bone (upper arm), radius and ulna (lower arm)
- Hand – Carpals (wrist), metacarpals (palm), phalanges (fingers)
- Identify and describe the bones of the pelvic girdle and explain its function
- 2 Coxal bones (two hip bones) – ilium, pubis, ischium
- Sacrum – connects coxal to spine
- Describe the three major parts of a coxal
bone
- Ilium – large flaring bone that is most of the hip
- Ischium – sit down bone at the bottom back of the hip
- Pubis – anterior section of hip
- Identify and describe the bones of the lower limb.
- Thigh – femur bone is the longest, strongest, and heaviest in the body
- Leg - the shin part with two bones: fibula and tibia
- Foot – tarsals (back of foot), metatarsals (medium foot), and phalanges (toes)
- Describe each type of joint movement
- Fibrous (synarthroses) – immovable, fibrous sutures in the skull, interlocked tightly
- Cartilaginous (amphiarthroses)– limited movement, can be epiphyseal in long bones or vertebrae on spine
- Synovial (diarthroses) – freely movable, joints of the limbs, contain synovial fluid
What happens to bone from childhood to adulthood? And what is osteoporosis?
Birth to Adulthood:
* Childhood to adulthood is the most dramatic changes
* Long bones are formed from cartilage, Flat bones in skull come from fibrous membranes (fontanels)
* Heads are huge compared to body and grow rapidly because of the brain
Older Adults:
* Bones should be physically stressed to remain healthy
* Osteoporosis is a bone thinning disease that affects older women giving them bone fractures easily
* Weight bearing joints also degenerate, with old people saying “my joints are getting stiff”
What is ossification, osteoblasts. Osteoclasts and osteocytes?
Ossification - bone growth
Osteoblasts - builder of bone
Osteoclasts - break down bone
Osteocytes - bone maintanence (mature osteoblasts)
True or false: bones are lifeless dry structures that don’t change once long bone growth is complete
False: bones are dynamic and active tissue with a blood supply
What is the Sagittal suture, the lambdoid suture and the coronal suture?
Coronal suture - separating frontal and parietal bones
Sagittal suture - at top of head separating two parietal bones
Lambdoid suture - separating parietal and occipital bone
What is a tendon and what is a ligament?
Tendons attach muscle to bone with connective tissue
Ligaments attach bone to bone with connective tissue
Which 2 minerals are stored in bone matrix?
Calcium and phosphorus
There must always be a ready supply of blood calcium to do what 3 things?
- Conduct nerves
- Contract muscles
- Blood clot
How many bones are in the adult human body?
206
Where and what does red and yellow bone marrow do?
Red marrow: becomes red blood cells
Yellow marrow: stores fat
Both are found in the centre of bone: the medullary cavity
In embryos and young children, what kind of cartilage do they have?
Hyaline cartilage
In embryos and young children, what kind of cartilage do they have?
Hyaline cartilage
In embryos and young children, what kind of cartilage do they have?
Hyaline cartilage
Bones are continuously remodeled based on these 3 things:
- Blood Calcium level
- Gravity
- Exercise
The Thyroid gland activates calcitonin when calcium levels are heightened, and they get _______ to deposit calcium in the bone
The parathyroid gland hormone activates when blood calcium levels are low and they get __________ to take calcium out of bone
Calcitonin - osteoblasts
PTH - osteoclasts
What attaches the first 7 pairs of ribs?
Costal (hyaline) cartilage
What are the true and false ribs?
1-7 true ribs attached by cartilage
8-12 false ribs
11-12 floating ribs
In the anatomical position, the radius is the _______ bone (medial or lateral)
Lateral
Is physical stress good for bones?
Yes bones should be pulled by muscles and gravity to remain strong or else they become thin and fragile
What are the two functions of joints?
- Hold the bones together
- Allow the skeleton to move
Where are most synovial joints found, limited movement, and most immovable joints found?
On the axial skeleton is where immovable and limited joints are found for protection of organs
On the appendicular skeleton is where the synovial freely moving joints are found
What is the true and false pelvis? And what is the difference between a female and male pelvis?
False pelvis - length of one ilium flare
True pelvis - hole in pelvis that baby goes through
Male pelvis - pubic arch less than 90 degrees, heavier
Female pelvis - lighter, larger flare, pubic arch more than 90 degrees
What are the only joints in the skull that are freely movable?
Jaw - temporomandibular joints
Which skull bones are the keystone of the face?
Maxillae because all facial bones except mandible connect to it
What are the 5 main regions of the vertebral column?
Cervival
Thoracic
Lumbar
Sacral
Coccyx
What make up the primary curvature and secondary curvatures of the spine?
Primary curvature - was there when we were born with a C shape spine, the thoracic and sacral region of spine
Secondary curvature - cervical and lumbar region developed later. They centre our weight in the lower limbs.
