Ex Phys Chapter 0/1 Review + part 2 of notes

The study of how the body’s structures and functions are altered when exposed to acute and chronic exercise is an appropriate definition of:

exercise physiology

homeostasis

how the body’s organ systems, tissues, cells, and molecules work and how their functions are integrated to regulate the body’s internal environment

What is the correct order of skeletal muscle hierarchical organization, from largest structure to smallest structure?

entire muscle, muscle fasciculus, muscle fiber, myofibril

Which of the following acts like  "spring" within the sarcomere, allowing it to produce increased force when quickly stretched

titin

Ca2+ ions (essential for contraction) are stored in the:

sarcoplasmic reticulum

What is the term for a single α-motor neuron and all the muscle fibers it directly signals?

motor unit

Which is the correct order of events in a voluntary contraction?

Action potential starts in the brain

Action potential travels down the spinal cord

Action potential arrives at alpha motor neuron

ACh crosses neuromuscular junction to receptors on sarcolemma, activating action potential

T-tubule transmits action potential

Ca2+ released by sarcoplasmic reticulum

troponin moves tropomyosin to reveal binding site on actin

myosin cross-bridging

Ca2+ pumped into SR

Lack of Ca2+ stops activation of troponin, allowing tropomyosin to cover the actin binding site

Sarcomere relaxes

Which of the following are characteristics of type I muscle fiber? (select all that apply)

high aerobic endurance

Appear as "dark meat" due to presence of fat, capillaries, and myoglobin

use fat and carbohydrates to produce ATP

During muscle contraction, in what order are muscle fibers recruited? 

slow to fast

Why does a sarcomere that is too short or too stretched produce less force?

not as many cross bridges can form

different ways the myosin head/thick filament proteins are structured are called

isoform

determines how quickly and powerfully muscle fibers can contract

protein structure

MHC

myosin heavy chain

which motor unit is smaller

type I

muscle fibers w a more highly developed SR

T II

concentric

shortens, maximal force decreases

eccentric

lengthens, maximal force increases at higher speed