Which of the following is/are a characteristic of skeletal muscle? Check all that apply. -
CORRECT ANSWER--Overlapping thin and thick filaments
-Striations
-Overlapping myosin and actin proteins
-Excitability
Assign each example to the universal muscle characteristic being described. -
CORRECT ANSWER-excitability
-placing muscle in a solution containing calcium & ATP
conductivity
-action potentials in the center of the fiber radiating to the ends
-depolarization of a single muscle fiber causing depolarization of adjacent muscle fibers
contractility
-creation of force
-pulling two bones closer together
-actively resisting the separation of two bones
elasticity
-a stretched muscle returning to it original length
-passively resisting the separation of two bones
extensibility
-stretching a muscle
-increasing sarcomere length
Identify the energy system that would be most important for each of the following
activities. - CORRECT ANSWER-Phosphagen system
-swatting at a mosquito
-jumping on the bed
-pitching a baseball
-swinging a golf club
-during a soccer game, jumping up to head a ball
Glycogen-lactic acid system
-running up a coupe flights of stairs
-running the 400-meter dash
-performing 25 push-ups
-during a 10K run, sprinting up a 200-meter-long hill
Aerobic Respiration supported by cardiopulmonary function
, -walking across campus
-sitting upright at your desk writing a report
-standing while giving a classroom presentation
-marathon running
-jogging on the beach
Click and drag each event into the appropriate category based on whether it would be
associated with a contraction or no contraction. - CORRECT ANSWER-No
concentration
-active transport of Ca^2+ into the sarcoplasmic reticulum
-a mutation to troponin that prevents it from binding Ca^2+
-a mutation to tropomyosin that prevents it from binding to troponin
-an inhibitor of voltage-gated Na+ channels
Contraction
-release of acetylcholine
-a mutation to tropomyosin that prevents it from binding actin
-presence of an organophosphate pesticide that inhibits acetylcholinesterase
-opening of calcium ion channels in the terminal cisterns
-exposure of the active sites on the actin filament
Match each event to the appropriate phase of a muscle twitch. - CORRECT ANSWER-
Latent period
-immediately follows stimulation of the muscle
-internal but not external tension generated
-excitation-conctraction coupling
-depolarization occurs in the T tubule
Contaction phase
-internal and external tension generated
-sarcomeres shorten
-power-stroke occurs
-myofilaments slide over one another
Relaxation phase
-Ca2+ transported back into the sarcoplasmic reticulum
-muscle tension decreases
Which of the following is/are true regarding muscular strength and conditioning? Check
all that apply. - CORRECT ANSWER--Blood capillary density will increase in slow
-Weight lifting does not increase the number of muscle fibers in a particular muscle
exercised.
-Long-term resistance training will increase the number of myofibrils in a particular
muscle exercised.