Quiz 1 / Exam 1 Flashcards
Movement Stability Communication Control of body openings & passage ways Heat production are all functions of:
Skeletal Muscle
Basic structural unit of a muscle is the:
Muscle fiber (cell) aka myofibril
Muscle fibers are grouped into bundles known as:
Fasciculi
Muscle fibers & fasciculi are bound together by:
Connective tissue
What are the functions of connective investment of muscle?
- Connect muscle to bone or other structures
- Provides a route through which nerves & blood vessels reach the muscle fiber
- Provide a non-contractile framework which allows the contraction of a muscle fiber to be transmitted
What are the 3 layers of connective tissue?
- Endomysium
- Perimysium
Epimysium
Delicate connective tissue sheath which surrounds each individual muscle fiber and connects it to adjacent muscle fibers
Endomysium
More dense layer which surrounds each fasciculi and divides the muscle into a series of separate compartments
Perimysium
Dense layer of connective tissue which surrounds the entire muscle & separates the muscle from surrounding tissue, organs and other muscles.
Epimysium
The __________ is continuous with deep fascia in the area & will continue as the TENDON of the muscle
Epimysium
Muscle fibers are extremely long and ______________, with the nuclei arranged around the __________ of the fiber.
Multi-nucleated, periphery
The contractile unit of the muscle
Myofilaments
Each fiber is contained w/in a tough, specialized membrane known as the
Sarcolemma
Type of increase in the size of a muscle, which is due to an increase in the size of each individual muscle fiber.
Hypertrophy
Increase in the size of a muscle due to an actual increase in the number of muscle fibers.
Hyperplasia
Refers to the cytoplasm of a muscle fiber.
Sarcoplasm
Associated with higher levels of continuous metabolic activity
Type 1 muscle fibers
Aerobic Metabolism is associated with what muscle type?
Type 1 muscle fibers
Anaerobic metabolism is associated with what muscle type?
Type 2 muscle fibers
The cell membrane:
Sarcolemma
Elaborate, tubular network which functions to store & transport calcium ions to the myofibrils
Sarcoplasmic Reticulum
Tubular invaginations of the sarcolemma which allow electrical impulses to enter the muscle fiber & make their way to the myofibrils
Transverse Tubules (T-system)
Functions of myoglobin
- Stores the needed oxygen that the fibers need to utilize for metabolism
- Has a greater affinity for oxygen than that of hemoglobin
Contractile apparatus of the muscle fiber
Myofibril
Myofibrils are formed from longitudinally oriented bundles of thick and thin filaments know as:
Myofilaments
Myofibrils are made of up:
I-bands
A-bands
H-bands
Z-lines
I-bands
Light areas
A-bands
Dark areas
H-bands
Light areas in the middle of each A-band
Z-lines
Thick dark line in the middle of each I-band
Each myofibril is composed of numerous units known as the __________, smallest functional unit of the muscle and runs from one Z-line to the next Z-line
Sarcomere
Contractile proteins consists of?
Actin and Myosin
Actin can be found primarily in the:
I-bands
Myosin can be primarily found in the:
A-bands
These two proteins interact with one another and thus create movement, a contraction
Actin and myosin
Act to inhibit the interaction of actin and myosin & thus prevent indiscriminate movement
Regulator proteins
Two most common regulatory proteins are?
Troponin and tropromyosin
Eliminates the inhibition caused by the regulatory proteins & thus allows muscle contraction to occur
Calcium
Nerve impulse from the _________ _______ stimulates the release of calcium from the sarcoplasmic reticulum
Transverse Tubules
The released calcium binds with the troponin molecules on the _______
Actin filaments
True / False The binding of calcium with troponin changes the shape of the nearby tropomyosin molecule and exposing the myosin biding site on the actin molecule
True
_____ allows the system to operate, by allowing myosin to interact with actin
ATP
Muscle uses 2 general metabolic methods to provide ATP— one works _______ and the other works ________
Aerobically and anaerobically
Aerobic pathway takes place in the?
Mitochondria
True/ False More efficient way to produce ATP in a muscle fiber
True
This pathway prefers fatty acids to produce ATP
Aerobic Pathway
Fatty acids are stored in the body’s fat cells as __________ and released into the blood during exercise
Triglycerides
This pathway depends on 2 substances to produce ATP
Anaerobic pathway
- Creatine phosphate and glycogen
First substance used by the anaerobic pathway & allows the muscle to contract at once
Creatine phosphate
Substance in the anaerobic pathway which produces ATP by the process known as glycolysis
Glycogen
Glycogen is stored in _________ or ________ ____ and the pathway works quickly
Muscle fiber or liver cells
What happens during PHASE 1 of exercise:
Only last a few min. And creatine phosphate & glycogen are the primary fuel sources. 20% of the total glycogen that is stored in a muscle maybe utilized during this phase
What happens during PHASE 2:
Shift in metabolism to the more efficient aerobic metabolism and the use of fatty acids to produce ATP
What happens during PHASE 3
Occurs as exercise intensifies, will se the muscle fibers going back to anaerobic production of ATP and thus the utilization of the remaining stored glycogen. During this phase that lactic acid can accumulate within the fibers.
Method to increase red blood cell concentration is using a synthetic type of:
Erythropoietin (EPO)
EPO is naturally occurring hormone produced in the?
Kidneys
This hormone travels to the bone marrow to produce red blood cells
Erythropoietin (EPO)
Motor Nerves transmit_____ / ______impulses from the CNS to each individual muscle fiber, the result of which is a _____ response (contraction)
Efferent/ Motor, Motor
Sensory Nerve Fibers convey to the CNS ________/______ impulses which originate within the muscle as a result of a contraction.
Afferent/ sensory
