Download HAP UNIT 7 STUDY GUIDE MUSCLES PART 1: OVERVIEW OF

HAP UNIT 7 STUDY GUIDE
MUSCLES
PART 1: OVERVIEW OF MUSCLES
1.
Changes chemical energy (in the form of ATP) into mechanical energy (with the
movement of muscle)
2. Fill in the following chart to contrast the three types of muscles:
Type
Found in what
Striated?
Voluntary ?
area of body?
skeletal
Attached to bone
Yes
yes
Cardiac
Heart
Yes
No
Smooth
Internal organs
No
no
3. Muscle need to be, excitable to receive messages from the brain, contractable to
move bone, extensible to stretch and elastic to “bounce back” into its original
shape.
PART 2: GROSS MUSCLE ANATOMY
4. Explain the meaning of the following prefixes and root words:
a. Mys/myo- muscle
b. Endo- inside
c. Epi- outside
d. Peri- near
e. Sarco- flesh (muscle)
f. Lemma- membrane
g. Plasm- cytoplasm
ill in #5-9 using the following wordbank:
5. Each muscle cell or fiber is surrounded by a connective tissue sheath or capsule
called the ENDOMYSIUM
6. A bundle of muscle fibers are called FASICLE and are surrounded by a collagen
sheath called PERIMYSIUM
7. These cell bundles are grouped together to make a muscle. The entire muscle is
bound together with a “overcoat” or EPIMYSIUM
8. All the sheaths or coverings converge together at the end of the muscle and form
the TENDON which connects the muscle to the bone.
9. The connective tissue that is coarse and fibrous that surrounds groups of muscles
and neighboring organs is called FASHIA
10. Label the following picture:
Tendon
Epimysium
Endomysium
Fiber
bone
Perimysium
Fascicle
(bundle)
Blood
vessel
Endomysium
PART 3: MICROSCOPIC ANATOMY OF THE FIBER (MUSCLE CELL)
11. Each cell is protected and strengthened by a permeable connective tissue
“overcoat” called the ENDOMYSIUM
12. The muscle cell plasma membrane that is found inside the endomysium is called
the SARCOLEMMA
13. Two organelles that are found in numerous amounts inside a muscle fiber
MITOCHONDRIA, NUCLEI
14. A special name for cytoplasm of a muscle cell SARCOPLASM
15. Nuclei are pushed aside by long ribbonlike organelles called SARCOMERES that
have light and dark bands which give the muscle its striped appearance.
16. Another name for muscle fiber is MYOFIBRILS
17. Rod-like organelles that run the length of a fiber and is divided into tiny
contractile segments called MYOFILAMENTS
18. Smaller structures that actually perform the movement in a muscle fiber are called
MYOFILAMENTS and come in two types MYOSIN (thick bands) and ACTIN
(thin bands).
19. Label the following diagram of the muscle cell:
actin
H
zone
Z line
mysin
sarcomere
PART 4: MUSCLE CONTRACTION
20. Explain how a muscle is told to contract by a nerve.
a. What is the muscle fiber like at rest? Sodium is outside the cell (overall
positive charge); potassium is inside (overall negative charge); cell is
impermeable to ions.
b. What happens to cause depolarization? The nerve releases acetylcholine
which travels across the synaptic cleft to the muscle.
c. What happens during depolarization? The neurotransmitter attaches to the
protein gate in the sarcolemma which opens it to sodium. Sodium moves
into the cell, making the outside an overall negative charge and inside
overall positive.
d. What happens during repolarization? The cell opens potassium gates and
potassium moves outside, returning the charges to normal (positive
outside, negative inside)
e. What happens during restoration? The cell uses ATP to pump sodium out
of the cell and potassium back into the cell to restore the ions to their
original locations.
f. How does a muscle stop contracting? Enzymes on the surface of the cell
break down the neurotransmitter to close sodium gates.
21. Explain the mechanism of contraction of a muscle using the theory outlined
below:
Use the following terms to guide your answer
a. In a resting muscle fiber- Actin and myosin sit close to each other but not
touching.
b. A nerve cell does what? And generates what? The nerve cell starts an
action potential by causing depolarization. This signal moves through the
sarcolemma and down into the T tubules/system.
c. What is released? Where does it go? Calcium is released from the t
tubules and travels down into the myofilaments. Where it binds to actin.
d. What now occurs? What forms? Actin changes shape and forms
crossbridges with myosin. Now they are physically touching.
e. Movement of myofilaments? The change of shape causes the crossbridges
to “snap back” and walk actin over the surface of myosin, causing the H
zone to disappear.
f. Need for energy? In what form is the energy found and what does it do?
ATP is used to release the calcium from the actin which releases the
crossbridges. If the muscle is not fully contracted, this will happen again.
22. Actin detaches and reattaches several times to fully contract the muscle.
23. The speed of the nerve signals to the muscle can cause tetanus (a fully contracted
muscle) and the more fibers or motor units in the muscle being signaled create a
larger contraction
PART 5: USING ENERGY FOR EXERCISE
24. There are two types of muscle fibers- red-slow twitch fibers create slower more
sustained contractions; white fast twitch fibers make faster, shorter contractions.
Most people have more/less of each kind.
25. You build up calcium in the t tubules to use for contraction; you improve enzyme
function by increasing the temperature.
26. You could pull a muscle or tear a tendon.
27. Making small tears in the fibers which repair themselves by branching and
stimulating them to make more myofibrils.
28. Muscle fibers can produce ATP using 3 different methods. Fill out the following
chart to describe these processes:
TAKES PLACE
ADVANTAG DISADVANTAG
METHOD
RAW
OF ATP
IN
MATERIALS E(S)
E(S)
PRODUCTI
NEEDED
ON
Creatine
1. cytoplasm
1.creatine
1. short quick 1. only lasts a few
PO4
phosphate
burst of
seconds
energy
2.ADP
Aerobic
Respiration
1. mitochondri Resting:
1. makes lots
a
1. oxygen of ATP
1. only works
with oxygen
2. slow process
2.fatty acid
Working:
1.oxygen
2.glycogen
Anaerobic
pathway
also called-
1. cytoplasm
1. glycogen
1. helps create
energy
without
oxygen
1. inefficient use
of sugar
2. causes
soreness
due to
lactic acid
buildup
PART 6: DISEASES AND DISORDERS
MATCH THE FOLLOWING DISEASES/DISORDERS TO THEIR SYMPTOMS
botulism -Toxin that is highly lethal; keeps acetylcholine from functioning; found in
improperly canned food
Myasthenia gravis -A disease where neuromuscular junction stops functioning causing
degeneration of muscle tissue
rigor mortis -Condition where muscles run out of ATP so myosin crossbridges can’t
release from actin
Trichinosis -A disease caused by worms that lay cysts in muscle tissue; caused by
improperly cooked and low quality pork.