Reference no: EM133930433
Questions
1. Long bones (like the humerus and femur) have an outer layer of __________ bone at the bulbous end which is called the_________. The inner layer of bone is called _spongy bone. The thin shaft of the long bone is called the ____________ and has a hollow core called the _medullary cavity__ which is filled with marrow.
2. Bones are covered in a layer called the _periosteum. It has two parts, the outer _fibrous layer which is made of collagen and __________ fibers that is continuous with the tendon that attaches local muscles to the bone. The inner layer is called the _______ layer and function to:
3. Short, irregular and flat bones have ______layers of bone, an inner ______ layer and two ________ bone layers that sandwich it. Particularly in the skull, the inner layer that is filled with red bone marrow acts as a soft, spongy layer that helps to absorb shock to prevent injury. This layer is called _________________.
4. Describe the composition and function(s) of the following aspects of osseous tissue
• Cells (osteogenic, osteoblasts, osteocytes & osteoclasts);
• Matrix (hydroxyapatite, collagen)
• Red bone marrow
5. Bones can grow both in ____ and ____. An increase in bone length only occurs at the ___ where the cartilage is being replaced by bone.
Growth in bone length is called _________ growth while growth in bone width is called _______________ growth.
In appositional growth, new bone is deposited osteoid tissue by osteoblasts that lay down matrix to form circumferential lamellae. At the same time, osteoclasts break down bone at the marrow cavity. Why?
6. In endochondral ossification, the skeleton is first made of _________ cartilage. Then primary ossification occurs, along with a thin section of bone along the outside edge called the _____ _________. Then _______invade the area, bringing in nutrients and a ______ cavity begins to form. A _____ ossification center now forms as well. At this stage of bone development, the fetus will be born with large medullary cavities and a secondary medullary cavity in one _______. As the child grows, there is a significant portion of cartilage left at the ________late and at the articular surface. At what age is this cartilage finally gone, leaving only an epiphyseal line? ________.
7. Describe the following microscopic structures of spongy bone:
a. spicules
b. trabeculae
c. red bone marrow
What is special about the function of spongy bone?
Where does it form most often?
8. Describe the following microscopic structures of compact bone:
• nutrient foramina
• perforating canals
• central canals
• circumferential lamellae
• interstitial lamellae
f. osteon
9. Relate nutritional requirements for bone health (minerals and proteins).
10. What is the function of collagen in bone?
What is the function of minerals in bone?
11. Resorption bays- cells often reside in there(pits in bone surface).
remodeling
Where do osteoclasts originate?
How many nuclei do they have?
Where are they located?
12. If blood calcium levels are low we need the bones to _________________________________(release/absorb) calcium.
* The hormone responsible for triggering this change is _____________________________________ which causes what to happen bringing the calcium levels back to normal?
13. If blood calcium levels are high we need the bones to ________________________________(release/absorb) calcium.
* The hormone responsible for triggering this change is ________________________________ which causes what to happen bringing the calcium levels back to normal?
14. Why is calcium important in our bodies? Where do we use it?
15. What effect would hyposecretion of the thyroid gland have on bones?
16. What effect would hypersecretion of the parathyroid gland have on bones?