Name:______

Period:______

CHAPTER 8 MUSCULAR SYSTEM

  1. Introduction: 3 types of muscles

a. ______muscle (striated or voluntary)

b. ______muscle (involuntary)

c. ______

  1. Structure of a Skeletal Muscle
  2. Skeletal muscles are part of a system that is composed of; skeletal ______tissue, ______tissue, blood, and ______tissue.
  3. Connective Tissue Coverings
  4. ______- connective tissue that ______one skeletal muscle from another.
  5. ______– growth of fascia beyond muscle; grows into bone’s ______; attaches muscles to ______.
  6. Aponeuroses-large sheet of ______tissue that connects ______muscles.
  7. Network of connective tissue from the outside in:
  8. ______: (epi=upon) surrounds entire muscle.
  9. ______: (peri=around) separates muscle into smaller bundles called ______.
  10. ______: (endo=within) between each muscle fiber within the fascicle.
  11. Skeletal Muscle Fibers/Cells
  12. Skeletal muscle fiber = ______or ______.
  13. Ability to ______and ______.
  14. Single cell may be full length of a muscle.
  15. Parts: (of muscle cell)
  16. ______: (sarco=flesh, lemm=rind or peel) cell membrane around muscle cell.
  17. ______: cytoplasm
  18. ______: several per muscle cell
  19. ______: cellular respiration, ______(in the form of ______).
  20. ______(organelle within muscle cell):______of muscle contraction;composed of 2 proteins:
  21. ______: thick filaments (myofilament)
  22. ______: thin filaments (myofilament)

*The arrangement of the proteins produces the light/dark patterns or striations.

  1. ______: unit of contraction within the myofibril. Striation pattern:
  2. ______ (light bands): thin ______filaments attached to Z lines.
  3. ______ (dark bands):thick ______filaments that overlap with actin.
  4. ______: defines single sarcomere.
  5. Network of membranes:for ______within the muscle fibers.
  6. ______reticulum: (Endoplasmic reticulum)
  7. Surrounds each ______
  8. Contains ______, used during contraction.
  9. ______tubules (T-tubules)
  10. Open to the ______of the sarcolemma.
  11. Extend ______deep into myofibrils.

d. Neuromuscular Junction

i. Neuromuscular Junction: connection between ______(Nerve cell from brain or spinal cord) and ______

1. Motor neuron fiber

a. Branches into surface of muscle fiber.

b. Contains synaptic ______; containers that store chemicals called, ______.

c. Motor end plate

1. The sarcolemma (cell membrane) is ______in this region where the motor ______fibers join the ______.

2. ______(ENERGY) and nuclei are abundant is this area.

3. How the Impulse travels.

i. The nerve impulse travels from the ______/______to the motor neuron.

ii. The synaptic vesicles ______the neurotransmitter (chemical) into the ______(gap between motor neuron and motor end plate).

iii. The chemicals cause a series of reactions to take place in muscle fiber and muscle ______.

e. ______= motor neuron (impulse from ______or spinal cord) + the muscle fibers/______that it controls.

III. Skeletal Muscle Contraction

a. Muscle contraction = the shortening of the ______.

b. Role of Actin and Myosin

i. ______: two twisted proteins with globular “heads”; ______. “THICK” filament

ii. ______: globular protein with ______sites for myosin. “THIN” filament

iii. ______of muscle contraction:

1. The ______cross-bridge attaches to the ______site on the ______and ______, ______on the actin filament. This ______the sarcomere.

2. After releasing, the ______, attaches to the ______binding site on the actin and ______again.

iv. Energy for the contraction comes from ______: ATP is broken down by the enzyme ______into ADP and ~P, releasing ______.

1. The muscle will contract as long as ______is present.

c. Events for Muscle Contraction

i. The motor neuron releases the neurotransmitter ______from the synaptic ______into the synaptic cleft. This ______the muscle contraction.

ii. Receptors in the ______detect the neurotransmitters, and the impulse spreads over the surface of the ______and into the ______, where it reaches the sarcoplasm of the muscle fiber.

iii. ______is released from the sarcoplasmic ______into the ______.

iv. In the presence of ______and ______myosin cross-bridges ______and ______on the actin filaments, causing the sarcomere to ______.

*SHORTEN = ______

d. Events of Muscle Relaxation

i. The enzyme ______decomposes the acetylcholine = muscle fiber no longer ______.

ii. ______is transported back into the ______reticulum.

iii. The ______between the actin and myosin separate, ______has to be present.

iv. The filaments slide ______= muscle ______.

e. Energy Sources for Contraction

i. Energy for contraction comes from ______.

ii. ______, in the ______, stores energy for the ______of ATP from ADP.

f. Oxygen Supply and Cellular Respiration

i. The breakdown of ______, in the mitochondria, produces ______.

1. ______respiration, in the presence of oxygen, yields 34 ATP/glucose.

ii. ______in RBCs carries oxygen to the muscles.

iii. ______, a ______in muscles, stores ______in muscles.

g. Oxygen Debt

i. During strenuous exercise the levels of oxygen ______, and ______accumulates as an end product of ______(without oxygen) respiration.

1. Lactic acid that accumulates in muscles causes the ______sensation during strenuous exercise.

2. The lactic acid is carried in the bloodstream to the ______to be converted.

ii. Oxygen Debt refers to the amount of ______required to ______the lactic acid, in the liver, back to ______.

h. Muscle Fatigue

i. Fatigue is when a muscle ______its ability to contract.

ii. Usually occurs due to an accumulation of ______.

iii. A muscle ______occurs due to a ______of ATP required to return the ______ions back to the ______reticulum so the muscle can ______.

j. Heat Production

i. The contraction of skeletal muscles is a source of ______for the body.

ii. Through the process of ______heat is lost as a by-product.

IV. Muscular Responses

One method of studying muscle function is to remove a single muscle fiber (cell) and connect it to a myogram, a device that records its response to electrical stimulation.

a. ______: minimal strength required to cause a contraction.

b. ______: a muscle fiber will contract to its full extent; it ______partially contract.

c. ______: a single short contraction, involving only a few motor units.

i. ______period: time delay between the stimulus and the contraction (< 0.01 sec.)

ii. ______: combined twitches (fibers unable to ______completely before next stimuli).

iii. ______contraction (______): contraction ______any relaxation.

d. muscle ______(tonus): ______contraction in the muscle fiber; due to ______impulses from the spinal cord, important in maintaining ______.

V. ______Muscle

a. Smooth Muscle Fibers

i. ______muscle cells are

1. Long with tapered ends.

2. Contain ______and ______, in random arrangements, therefore ______striations.

3. There are two types of smooth muscle:

-______smooth muscle

-______muscle

ii. Multiunit smooth muscle is

1. It is located in the ______of the eye and in ______.

2. The muscle fibers are ______, not in sheets.

iii. Visceral smooth muscle is

1. It is located in the walls of ______organs.

2. These fibers can stimulate one another and display ______. They are responsible for ______(rhythmic wavelike motion) in hollow organs and tubes.

b. Smooth Muscle Contraction

i. Very similar to skeletal muscle.

ii. Two neurotransmitters stimulate and inhibit smooth muscle

1. ______(for skeletal muscles too)

2. ______

iii. ______(chemical messengers) also affect smooth muscle.

iv. Smooth muscle is ______to contract and relax, compared with skeletal muscle, but can contract ______using the same amount of ATP.

VI. ______Muscle

a. Contraction is ______to skeletal and smooth muscle.

b. Cardiac muscle gets an ______supply of ______, allowing it to contract for longer periods.

c. ______join cells and ______the force of the contraction form one cell to the ______.

d. Cardiac muscle is ______and rhythmic, the heart contracts as a ______.

FYI

*______– Stiffening of the muscles after death caused by the ______of ATP. The actin/myosin cross-bridges ______detach which prevents muscle relaxation. (Approximate time line (temperature depending) if the body is; warm & not still <3 hours, warm & stiff 3-8 hours, cold & stiff 8-36 hours, and cold & not stiff 36> hours.)

*Muscle ______– ______in muscle size, therefore ______blood supply and energy (mitochondria) needed; caused by ______of use.

*Muscle ______– ______in muscle size.

*______fibers – ______resistant muscles, more ______, more ______, created by swimming and running.

*______fibers – faster to ______, larger muscle fibers. Created by weight lifting.

*______– rare paralytic illness caused by a nerve toxin that ______signals to the muscles. It is produced by the bacterium Clostridium botulinum. Usually associated with food poisoning.

Revised 10-09