TAMU KINE 433- Exam 2 questions with verified
answers
Skeletal Muscle Ans✓✓ --voluntary
-Regulated by the CNS
Cardiac/Smooth Muscle Ans✓✓ --involuntary
-regulated by the ANS
Muscle is composed of Ans✓✓ -MANY muscle fibers
Muscle fibers vary in Ans✓✓ -contractile properties
Muscle fibers range in diameter from Ans✓✓ -10mm-120mm
Muscle fibers are Ans✓✓ -multinucleated
Sarcomere is the ____________ of a myofibril Ans✓✓ -functional unit
Thick filaments are composed of Ans✓✓ -myosin
Thin filaments are composed of Ans✓✓ --actin
-tropomyosin
-troponin
,The intent to exercise arises in the _______ of the brain Ans✓✓ -motor cortex
Central Command activates which things simultaneously? Ans✓✓ --muscle
-CV system
-respiratory system
The alpha motor neuron carries an AP from ______ to _____ Ans✓✓ -CNS to
muscle fibers
Motor Unit Ans✓✓ -an alpha motor neuron and all the muscle fibers it
innervates
An alpha motor neuron releases Ans✓✓ -ACh, this turns an electrical signal to a
chemical one
ACh binds to Ans✓✓ -a nicotine receptor, turning a chemical signal to an
electrical one
Action potentials travel down T tubules to Ans✓✓ -the sarcoplasmic reticulum
The sarcoplasmic reticulum releases Ans✓✓ -Ca++
Ca++ binds to Ans✓✓ -troponin
Ca++ binding to troponin pulls tropomyosin off Ans✓✓ -active sites
, The powerstroke happens when Ans✓✓ -myosin binds to actin and tilts
In a relaxed muscle fiber Ans✓✓ --intracellular Ca++ is low
-active site is blocked
-myosin cant bind actin
In a contracting muscle fiber Ans✓✓ --Ca++ is released from SR
-Ca++ binds troponin
-Active site is exposed
-Myosin head attaches
In a fully contracted muscle contraction Ans✓✓ --myosin head tilts
-ATP binds to myosin head
-Myosin head detaches
Muscle contraction stops when Ans✓✓ --central command is removed
-ACh degraded
-Ca++ is pumped back into the SR
Type I fibers Ans✓✓ --high mitochondria
-high capillary network
Type IIa fibers Ans✓✓ -moderate mitochondria and capillary network
Type IIx Ans✓✓ --low mitochondria
answers
Skeletal Muscle Ans✓✓ --voluntary
-Regulated by the CNS
Cardiac/Smooth Muscle Ans✓✓ --involuntary
-regulated by the ANS
Muscle is composed of Ans✓✓ -MANY muscle fibers
Muscle fibers vary in Ans✓✓ -contractile properties
Muscle fibers range in diameter from Ans✓✓ -10mm-120mm
Muscle fibers are Ans✓✓ -multinucleated
Sarcomere is the ____________ of a myofibril Ans✓✓ -functional unit
Thick filaments are composed of Ans✓✓ -myosin
Thin filaments are composed of Ans✓✓ --actin
-tropomyosin
-troponin
,The intent to exercise arises in the _______ of the brain Ans✓✓ -motor cortex
Central Command activates which things simultaneously? Ans✓✓ --muscle
-CV system
-respiratory system
The alpha motor neuron carries an AP from ______ to _____ Ans✓✓ -CNS to
muscle fibers
Motor Unit Ans✓✓ -an alpha motor neuron and all the muscle fibers it
innervates
An alpha motor neuron releases Ans✓✓ -ACh, this turns an electrical signal to a
chemical one
ACh binds to Ans✓✓ -a nicotine receptor, turning a chemical signal to an
electrical one
Action potentials travel down T tubules to Ans✓✓ -the sarcoplasmic reticulum
The sarcoplasmic reticulum releases Ans✓✓ -Ca++
Ca++ binds to Ans✓✓ -troponin
Ca++ binding to troponin pulls tropomyosin off Ans✓✓ -active sites
, The powerstroke happens when Ans✓✓ -myosin binds to actin and tilts
In a relaxed muscle fiber Ans✓✓ --intracellular Ca++ is low
-active site is blocked
-myosin cant bind actin
In a contracting muscle fiber Ans✓✓ --Ca++ is released from SR
-Ca++ binds troponin
-Active site is exposed
-Myosin head attaches
In a fully contracted muscle contraction Ans✓✓ --myosin head tilts
-ATP binds to myosin head
-Myosin head detaches
Muscle contraction stops when Ans✓✓ --central command is removed
-ACh degraded
-Ca++ is pumped back into the SR
Type I fibers Ans✓✓ --high mitochondria
-high capillary network
Type IIa fibers Ans✓✓ -moderate mitochondria and capillary network
Type IIx Ans✓✓ --low mitochondria
