(Insert excuse for being so slow with the anatomy and physiology posts)
Ok as you know, in the stressful time of the last 3 weeks of class I am trying to learn the content, here are some very brief question and answers that will give you a heads up on what i will be posting from my notes when I actually get around to it.
How do the structural proteins within the sarcomeres support the contractile filaments to provide movement?
Sarcomeres are compartments which house contractile filaments, the structural proteins are one of three types of proteins in the muscle. The structural proteins keep the thick and thin filaments in alignment – this gives elasticity and extension to microfibril, it also links the microfibril to the sarcolemma and extracellular matrix. Some key proteins are : titin, alpha actin, mysomesin, nebulin and dystrophin
What are the effects of aging on the muscular system?
The skeletal muscles will be replaced with fat if not used around the age of 30. As the individual gets older, their reflexes and strength decrease. In order to keep the muscle and strength you need to use it and continue to use it. Due to aging, a change in fibre may be made to slow oxidative fibres because a lack of use.
You are working in a health care facility and sadly you discover that one of your patients has died. On examination you discover that your patient is quite rigid. Discuss the physiology of this state.
This rigidity is due to the calcium +2 ions, which leak out of the SR and allows myosin heads to bind to actin (think back to muscle contractions, it was a step in the cycle that they attached). The flow of blood has stopped so the ATP synthesis has stopped and the cross bridges can’t detach. When the proteolytic enzymes begin to digest the decomposing cells then the ridged state of the patient will cease. This state is called rigor mortis, it is when the muscles become ridged, it occurs around 3-4 hours after death and will usually last 24 hours.