SLCC Physiology Exam 3 (Ch. 12-16) Questions with Complete Solutions
5 views 0 purchase
Module
SLCC
Institution
SLCC
Sarcolemma - Answer-surrounding cell membrane around muscle
Sarcoplasmic reticulum - Answer-The smooth ER of a muscle cell, Ca2+ reservoir, around each myofibril in the muscle cell.
myofibrils - Answer-bundle of contractile proteins within muscle
sarcomere - Answer-functional unit of muscl...
SLCC Physiology Exam 3 (Ch. 12-16)
Questions with Complete Solutions
Sarcolemma - Answer-surrounding cell membrane around muscle
Sarcoplasmic reticulum - Answer-The smooth ER of a muscle cell, Ca2+ reservoir,
around each myofibril in the muscle cell.
myofibrils - Answer-bundle of contractile proteins within muscle
sarcomere - Answer-functional unit of muscle within myofibrils
Z lines - Answer-dense set of proteins, has actin protein
M line - Answer-not quite as dense, myosin protein stays in the middle
A band - Answer-from one end to another of myosin, partial overlap of actin/myosin
H zone - Answer-only where myosin, no overlap of actin in M line
I band - Answer-one end of myosin in one sarcomere, only overlap of actin, no myosin
myosin - Answer-thick filaments. shortens both sides of myofibril, pulls actin toward M
line, decreases H zone, shortens I band
actin - Answer-thin filaments. made of subunits, has myosin binding sites
tropomyosin - Answer-controlled by actin, long filament, when muscle is relaxed, covers
binding sites of actin
troponin - Answer-changes shape when Ca binds to it. pulls tropomyosin from binding
sites and exposes actin binding sites. controlls tropomyosin
Ca controls ___________ - Answer-contraction
titin - Answer-acts like anchor to anchor myosin to z lines on both sides
sliding filament model - Answer-The idea that muscle contraction is based on the
movement of thin (actin) filaments along thick (myosin) filaments, shortening the
sarcomere
Cross-bridge cycle - Answer-myosin grabs actin, pulls actin toward cent of sarcomere
(towards m line), ATP provides energy to detach myosin head and cock it back to
original shape, process repeats.
, No calcium- no contraction
No ATP- no release
excitation-contraction coupling of skeletal muscle - Answer--depolarization of
sarcolemma (excitation)
-depolarization of T-tubule
-DHP receptors in membrane respond to voltage change
-release of calcium from sarcoplasmic reticulum
-calcium binds to troponin which moves topomyosin away from the binding sites
-cross bridge cycle (contraction of muscle)
Does skeletal muscle have pacemaker cells? - Answer-No
termination of contraction - Answer-calcium gets pumped quickly back into SR, stops
sending signal
isometric and isotonic twitches - Answer-...
summation and tetanus - Answer-1. summation is where muscle contractions combine
and become stronger and more prolonged
2. tetatnus is the continous sustained contraction where muscle cannot relax. will
release if maintained.
fiber diameter - Answer-increased diameter --> increased myofibrils in parallel -->
increased force production
length and tension - Answer-Max length that skeletal muscle can be stretched
(stretched too far it loses the ability to contract b/c actin and myosin heads are too far to
bind)
motor units - Answer-a single motor neuron and all muscle fibers innervated by it
muscle recruitment - Answer-increase in the # of motor units being used to increase
strength of contraction
What are the 3 muscle fiber types? - Answer-Slow oxidative, fast oxidative, fast
glycolytic
Slow oxidative - Answer-Makes a lot of ATP, fatiques slowly, has to have oxygen, small
diameter, little tension, darkest color. Lots of blood taking oxygen using myoglobin.
Fast oxidative - Answer-Makes a lot of ATP, fatigues slowly, pretty fast but not as fast
as fast glycolytic, carries myoglobin, medium diameter, medium color.
Fast glycolytic - Answer-Not making a lot of ATP, fatigues quickly, fast, doesnt use
oxygen- only glycolysis, light color, large diameter
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller lectknancy. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £12.73. You're not tied to anything after your purchase.
