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”