Hi guys
Here's a few questions to help you get ready for the skeletal system session on Wednesday. Access the session outline on MyUni to help you with the answers.
1. What are the functions of the skeletal system. Expand on the term 'haematopoiesis'
2. How are bones classified?
3. Why is bone considered as a connective tissue? Does it follow the 'normal' characteristics of connective tissue? How is it modified?
4. Define the following terms:
a. Diaphysis
b. Epiphysis
c. Periosteum
d. Sharpey's fibres.
lets a pre lecture lively discussion!
I answered alot of the last question, so I'll just answer one little bit of this one.
ReplyDelete'Haematopoiesis' is the process of formation of new blood cells from a stem cell precursor (a multipotential haematopoietic stem cell (HSC)if you want to get really technical).
These cells include plasma cells, red blood cells (erythrocytes), mast cells, lymphocytes and other white blood cells (basophils, neutophils, eosinophils and macrophages just for those of you interested.)
Basically the HSC's reside in the bone marrow and proliferate into more HSC's, some of which mature into blood components while others remain HSC's to continue the cycle.
There are many other processes involved, but I dont think we need to get that technical for this course :)
what are the functions?
ReplyDelete-support
-storage of minerals and lipids
-blood cell production (haematopoiesis): red blood cells, white blood cells and other blood elements are produced in red marrow which fills the internal cavities of many bones.
-protection: eg ribs protect heart&lungs, skulls enclose the brain
-leverage: change the magnitude and direction of the forces generated by skeletal muscles.
2) how are bones classified?
-long bones: relatively long and slender, located the arm, thigh,palms etc
-flat bones: have thin roughly parallel surfaces, forms the roof of the skull
-sutural bones(Wormian bones): are small,flat,irregular shaped bones betwenn the flat bones of the skull, like pieces of jigzaw puzzle
-irregular bones: have complex shapes with short, flat, notched,or ridged surfaces, like the spinal vertebrae, the bones of pelvis
-short bones: small and boxy, examples include the bones of wrist (carpal) and ankles(tarsal)
-sesamoid bones: generally small, flat, and shaped somewhat like sesame seed, develop inside the tendons, such as patella ( kneecap)
4)define the following terms?
-diaphysis: it means the tubular shaft the bone
-Epiphysis: at each end of the bone, the expanded area which normally consist of spongy bone are known as epiphysis
-periosteum: the superficial layer of compact bone ( the shaft of the bone-diaphysis?) is wrapped by periosteum, a membrane with a fibrous outer layer and a cellular inner layer.
-Sharpy fibers (perforating fibers) : collagen fibers incorporated into bone tissue from tendons and ligaments as well as from the superficial periosteum, they attach the tendons and ligaments into the general structure of the bone, providing a much stronger attachment.
Wow guys.. great work!
ReplyDeleteSophie