BIOL 251 Exam #2 Review Questions With
Correct Answers
Muscles |make |up |how |much |of |your |weight? |- |CORRECT |ANSWER✔✔-about |1/2
What |are |the |three |types |of |muscles? |- |CORRECT |ANSWER✔✔-skeletal, |smooth, |cardiac
Muscles |are |specialized |to |convert |____ |energy |to |____ |energy. |- |CORRECT |ANSWER✔✔-
chemical, |mechanical
How |many |skeletal |muscles |are |in |the |human |body? |- |CORRECT |ANSWER✔✔-more |than |600
Skeletal |muscle |includes: |- |CORRECT |ANSWER✔✔-skeletal |muscle |tissue, |connective |tissues, |
nerves |and |blood |vessels
Skeletal |muscles |do |not |contract |until |what |occurs? |- |CORRECT |ANSWER✔✔-They |are |
stimulated |by |a |nerve |to |do |so. |This |is |different |from |cardiac |and |smooth |muscle.
Skeletal |muscle |cells |are |also |called |- |CORRECT |ANSWER✔✔-muscle |fibers
What |are |the |connective |tissues |of |muscles? |- |CORRECT |ANSWER✔✔-endomysium, |
perimysium, |epimysium, |fascia
Endomysium |- |CORRECT |ANSWER✔✔-Thin |sleeve |that |surrounds |each |muscle |fiber, |creates |
room |for |capillaries |and |nerve |fibers |to |reach |every |muscle |cell.
,Perimysium |- |CORRECT |ANSWER✔✔-Sheath |that |bundles |muscle |fibers |into |units |called |
fascicles. |Larger |blood |vessels, |nerves, |and |stretch |receptors |will |be |found |within |this |sheath.
Epimysium |- |CORRECT |ANSWER✔✔-Fibrous |sheath |that |surrounds |the |entire |muscle |and |
bundles |multiple |fascicles |together.
Fascia |- |CORRECT |ANSWER✔✔-Sheet |of |connective |tissue |outside |of |the |epimysium |that |
separates |muscles |from |one |another.
What |is |direct |vs |indirect |attachment? |- |CORRECT |ANSWER✔✔-Direct: |looks |like |directly |
attached, |but |is |not, |short |connection |of |collagen |fibers. |
Indirect: |attaches |by |tendon, |obvious |band.
What |are |the |characteristics |of |muscle? |- |CORRECT |ANSWER✔✔-excitability: |muscle |cells |can |
become |excited |electrically
conductivity: |electrical |signals |will |travel |along |the |cell
contractility: |muscle |cells |and |shorten |when |stimulated
extensibility: |muscle |cells |can |stretch |between |contractions
elasticity: |when |a |muscle |cell |is |stretched |and |then |released, |it |recoils |to |a |shorter |length.
Is |skeletal |muscle |voluntary |or |involuntary? |- |CORRECT |ANSWER✔✔-voluntary
Why |are |there |striations |in |muscle |fibers |(skeletal |muscle)? |- |CORRECT |ANSWER✔✔-Due |to |
the |overlapping |arrangement |of |contractile |proteins.
Structure |of |skeletal |muscle |fibers |- |CORRECT |ANSWER✔✔-Sarcolemma: |plasma |membrane |
with |T |tubules |(infoldings).
Sarcoplasm: |cytoplasm. |Made |of |long |proteins |called |myofibrils/myofilaments. |Myoglobin, |
glycogen |strorage.
, Sarcoplasmic |reticulum: |smooth |endoplasmic |reticulum, |surround |each |myofibril. |High |
amounts |of |calcium, |which |is |important |for |contraction, |are |stored |there.
Sacrolemma |- |CORRECT |ANSWER✔✔-Plasma |membrane |of |a |muscle |fiber |that |forms |T |
tubules |(tubular |infoldings).
Sarcoplasm |- |CORRECT |ANSWER✔✔-Cytoplasm |of |a |muscle |cell. |Made |of |long |proteins |called |
myofibrils. |Contains |a |large |amount |of |glycogen |as |well |as |myoglobin |(an |oxygen |binding |
protein).
Sarcoplasmic |reticulum |- |CORRECT |ANSWER✔✔-Smooth |endoplasmic |reticulum, |surround |
each |myofibril. |High |amounts |of |calcium, |which |is |important |for |contraction, |are |stored |there.
What |are |the |three |kinds |of |myofilaments? |- |CORRECT |ANSWER✔✔-thick, |thin, |elastic
What |is |the |structure |of |thin, |thick, |and |elastic |myofilaments? |- |CORRECT |ANSWER✔✔-Thick: |
consists |of |many |molecules |of |protein |myosin
Thin: |is |made |of |two |intertwined |strands |of |actin. |Each |bead |of |the |actin |has |an |active |site |
that |can |bind |to |the |head |of |a |myosin |molecule. |Also |includes |the |protein |tropomyosin, |which
|covers |these |active |sites |at |rest. |Each |tropomyosin |has |troponin |bound |to |it.
Elastic: |composed |of |titin, |anchors |the |ends |of |thick |filaments |to |the |Z |line.
Overall |structure |of |striations |and |sarcomere |- |CORRECT |ANSWER✔✔-~ |Striated |muscle |has |
dark |A |bands |(thick |filaments |side |by |side, |part |of |the |A |band |is |where |thick |and |thin |
filaments |overlap) |alternating |with |lighter |I |bands
~ |In |the |middle |of |an |A |band, |there |is |a |H |band, |where |thin |filaments |do |not |reach
~ |In |the |middle |of |the |H |band, |the |M |line |links |thick |filaments |together
~ |I |bands |have |thin |filaments, |not |thick |filaments. |Each |I |band |is |bisected |by |the |Z |line, |which |
provides |anchorage |for |thin |and |elastic |filaments
~ |Sarcomere: |z |line |to |z |line, |functional |contractile |unit |of |muscle |fiber
Correct Answers
Muscles |make |up |how |much |of |your |weight? |- |CORRECT |ANSWER✔✔-about |1/2
What |are |the |three |types |of |muscles? |- |CORRECT |ANSWER✔✔-skeletal, |smooth, |cardiac
Muscles |are |specialized |to |convert |____ |energy |to |____ |energy. |- |CORRECT |ANSWER✔✔-
chemical, |mechanical
How |many |skeletal |muscles |are |in |the |human |body? |- |CORRECT |ANSWER✔✔-more |than |600
Skeletal |muscle |includes: |- |CORRECT |ANSWER✔✔-skeletal |muscle |tissue, |connective |tissues, |
nerves |and |blood |vessels
Skeletal |muscles |do |not |contract |until |what |occurs? |- |CORRECT |ANSWER✔✔-They |are |
stimulated |by |a |nerve |to |do |so. |This |is |different |from |cardiac |and |smooth |muscle.
Skeletal |muscle |cells |are |also |called |- |CORRECT |ANSWER✔✔-muscle |fibers
What |are |the |connective |tissues |of |muscles? |- |CORRECT |ANSWER✔✔-endomysium, |
perimysium, |epimysium, |fascia
Endomysium |- |CORRECT |ANSWER✔✔-Thin |sleeve |that |surrounds |each |muscle |fiber, |creates |
room |for |capillaries |and |nerve |fibers |to |reach |every |muscle |cell.
,Perimysium |- |CORRECT |ANSWER✔✔-Sheath |that |bundles |muscle |fibers |into |units |called |
fascicles. |Larger |blood |vessels, |nerves, |and |stretch |receptors |will |be |found |within |this |sheath.
Epimysium |- |CORRECT |ANSWER✔✔-Fibrous |sheath |that |surrounds |the |entire |muscle |and |
bundles |multiple |fascicles |together.
Fascia |- |CORRECT |ANSWER✔✔-Sheet |of |connective |tissue |outside |of |the |epimysium |that |
separates |muscles |from |one |another.
What |is |direct |vs |indirect |attachment? |- |CORRECT |ANSWER✔✔-Direct: |looks |like |directly |
attached, |but |is |not, |short |connection |of |collagen |fibers. |
Indirect: |attaches |by |tendon, |obvious |band.
What |are |the |characteristics |of |muscle? |- |CORRECT |ANSWER✔✔-excitability: |muscle |cells |can |
become |excited |electrically
conductivity: |electrical |signals |will |travel |along |the |cell
contractility: |muscle |cells |and |shorten |when |stimulated
extensibility: |muscle |cells |can |stretch |between |contractions
elasticity: |when |a |muscle |cell |is |stretched |and |then |released, |it |recoils |to |a |shorter |length.
Is |skeletal |muscle |voluntary |or |involuntary? |- |CORRECT |ANSWER✔✔-voluntary
Why |are |there |striations |in |muscle |fibers |(skeletal |muscle)? |- |CORRECT |ANSWER✔✔-Due |to |
the |overlapping |arrangement |of |contractile |proteins.
Structure |of |skeletal |muscle |fibers |- |CORRECT |ANSWER✔✔-Sarcolemma: |plasma |membrane |
with |T |tubules |(infoldings).
Sarcoplasm: |cytoplasm. |Made |of |long |proteins |called |myofibrils/myofilaments. |Myoglobin, |
glycogen |strorage.
, Sarcoplasmic |reticulum: |smooth |endoplasmic |reticulum, |surround |each |myofibril. |High |
amounts |of |calcium, |which |is |important |for |contraction, |are |stored |there.
Sacrolemma |- |CORRECT |ANSWER✔✔-Plasma |membrane |of |a |muscle |fiber |that |forms |T |
tubules |(tubular |infoldings).
Sarcoplasm |- |CORRECT |ANSWER✔✔-Cytoplasm |of |a |muscle |cell. |Made |of |long |proteins |called |
myofibrils. |Contains |a |large |amount |of |glycogen |as |well |as |myoglobin |(an |oxygen |binding |
protein).
Sarcoplasmic |reticulum |- |CORRECT |ANSWER✔✔-Smooth |endoplasmic |reticulum, |surround |
each |myofibril. |High |amounts |of |calcium, |which |is |important |for |contraction, |are |stored |there.
What |are |the |three |kinds |of |myofilaments? |- |CORRECT |ANSWER✔✔-thick, |thin, |elastic
What |is |the |structure |of |thin, |thick, |and |elastic |myofilaments? |- |CORRECT |ANSWER✔✔-Thick: |
consists |of |many |molecules |of |protein |myosin
Thin: |is |made |of |two |intertwined |strands |of |actin. |Each |bead |of |the |actin |has |an |active |site |
that |can |bind |to |the |head |of |a |myosin |molecule. |Also |includes |the |protein |tropomyosin, |which
|covers |these |active |sites |at |rest. |Each |tropomyosin |has |troponin |bound |to |it.
Elastic: |composed |of |titin, |anchors |the |ends |of |thick |filaments |to |the |Z |line.
Overall |structure |of |striations |and |sarcomere |- |CORRECT |ANSWER✔✔-~ |Striated |muscle |has |
dark |A |bands |(thick |filaments |side |by |side, |part |of |the |A |band |is |where |thick |and |thin |
filaments |overlap) |alternating |with |lighter |I |bands
~ |In |the |middle |of |an |A |band, |there |is |a |H |band, |where |thin |filaments |do |not |reach
~ |In |the |middle |of |the |H |band, |the |M |line |links |thick |filaments |together
~ |I |bands |have |thin |filaments, |not |thick |filaments. |Each |I |band |is |bisected |by |the |Z |line, |which |
provides |anchorage |for |thin |and |elastic |filaments
~ |Sarcomere: |z |line |to |z |line, |functional |contractile |unit |of |muscle |fiber
