2/11- Muscular System Continued Part 2 (Exam 1) Flashcards
What is Ca+2 (calcium ion) used for?
Attaches to troponin and changes it’s shape and moves tropomyosin away from the active site on actin
Muscular system shuts down without it
What is the Sarcoplasmic Reticulum (SR)?
Stores calcium ions in muscle cells
Highly modified smooth endoplasmic reticulum
Depolarization releases the calcium directly on sarcomere
Then collects it and stores it again
What is a sarcolemma or myolemma?
Cell membrane of muscle cells
What is depolarization?
Acetylcholine is released from synaptic cleft and ion channels open
Action potential on surface till tubes
Holes on surface of muscle cell has tubes and lets calcium in
Tubes get touched by SR and depolarization jumps over on sarcomere
Troponin changes shape
SR collects Ca and stores it
What are transverse tubules or T tubules?
The holes in a muscle cell that opens into tubes
Why are skeletal muscles striated?
Sarcomeres
What is the z line?
Edges of sarcomere that get pulled to center when contracted
The start and end of each sarcomere
What is the zone of overlap in the a band?
Dark edges
Myosin and actin overlap
What is the h zone of the a band?
Myosin only
What is the I band?
Actin only
What is the m line in the h zone?
Line running through the h zone
Connect myosin to one another
What is adenosine triphosphate (ATP)?
Breaks cross bridges formed when myosin attaches to active site of actin
Resets myosin
A nucleotide
Not a good way to store long term energy
Unstable
Muscles keep 2 seconds worth of energy of ATP around
What is creatine phosphate?
ATP + creatine——-> creatine phosphate + ADP
Take phosphate that Is unstable from ATP and give it to creatine creating creatine phosphate and it’s more stable
ATP becomes ADP
Creatine phosphate + ADP——> creatine + ATP
Gives another 15 seconds of contraction
What is creatine phosphokinase (CPK) (CK)?
Enzyme that helps carry out reaction of:
Creatine phosphate + ADP——> creatine + ATP
What is glycogen?
Stored in muscle cells
Human version of starch
Glucose molecules put together
Break apart get glucose
What is aerobic respiration?
Process that creates ATP
Going to use ATP as soon as it’s made
Needed if you need energy for long time
What are the steps of aerobic respiration?
Glycogen——> glucose—-(glycolysis)—-> Pyruvic acid or pyruvate——> kreb’s cycle
Before Pyruvic acid- 2 ATPs
End of Kreb’s cycle- CO2 (waste) and 2 ATPs
Electron transport chain- O2 in and 34 ATPs out
Kreb’s and electron transport chain happen in mitochondria
What is the steps of anaerobic or fermentation?
Glycogen—-> glucose——(glycolysis)—-> pyruvic acid or pyruvate——> lactic acid and CO2 (waste)
Before pyruvic acid- 2 ATPs
What are 3 things that can cause muscle fatigue?
1) run out of metabolic stores (glycogen and or blood sugar)
2) not enough O2
3) waste product of anaerobic respiration is lactic acidosis and interferes with the proteins
Muscle begins to fail cause of either or all reasons
What happens with lactic acid when you sleep?
Reverts to pyruvic acid with O2
Goes through liver
What does yeast make as a result of the anaerobic respiration?
Ethanol or ethyl alcohol
What is the recovery period?
After muscles fatigue
Lasts up to hours to days
Replenish blood sugar and glycogen
Getting rid of lactic acid
Getting O2
Pay oxygen debt
What is oxygen debt?
During exercise you need to replenish O2
When you pant
What is hypertrophy?
Over growth of the muscle
Making muscle cells bigger
What is atrophy?
Muscle breaks down
Can be bad
What is cardiac muscle?
ONLY found in heart
Striated
Actin and myosin slid on each other causing sarcomeres and striations
Involuntary
All electrically interconnected
Depolarize one cell all depolarize
What are gap junctions?
Stained and appear as intercalated disc
Space in cell for things to pas through
What are ions?
Charged atoms
Flow from one cell to the next using gap junctions
Roughly like electric current
What is smooth or visceral muscle?
Found in:
1) wall of digestive organs
2) wall of small air passageways in lungs
3) found in blood vessels
No striations
The actin and myosin do not slide on each other and don’t form sarcomeres
Involuntary
