HBIO 320 MIDTERM 1 EXAM QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS GRADED A++
what is anatomy? what are the 3 types?
-anatomy: the study of structure and parts of living organisms
1. gross: identify and name structure
2. histology: tissue characteristics
3. functional: function
What is physiology? what are the 2 viewpoints?
-physiology: the study of functions and mechanisms of living system
1. teleological: why? (evolutionary process)
2. mechanistic: how? (cellular processes)
what are the 3 types of muscles and its special characteristic?
1. skeletal: voluntary, multinucleated, striated
2. cardiac: involuntary, uninucleated, striated with branches and intercalated disks
3. smooth: involuntary, uninucleated, not striated
what are the 3 macrostructures of muscles and what are their special
characteristic?
1. parallel (fusiform, convergent): fibers run parallel to axis of force generation. they are
FASTER bc more distance is shortened per sec since fibers are straight, not angled
2. pennate (uni, bi, multi): fibers run at angle to force generation axis. they are
,STRONGER bc more fibers per physiological cross-section
3. circular: fibers run in concentric rings and act as sphincters
what is PCSA?
-physiological cross sectional area: the cross section of a muscle PERPENDICULAR to
its fibers
structure of skeletal muscle
muscle (covered by epimysium), fascicle (perimysium), fiber (endomysium), myofibril,
sarcomere, myofilaments (thick and thin)
label a sarcomere, with bands, thick and thin filaments and their structural
proteins
-z disc to z disc: sarcomere (origin of thin filament)
-I band: only thin
-A band: entire thick, includes thin
-H band: only thick
-M line: middle of H band (origin of thick filament)
what is thick filament made of? draw the structure of it
-myosin II
-light meromyosin: alpha-helical tail + heavy meomyosin: neck and head (contains
ATPase and actin-binding domain)
-the whole molecule is heavy, but the head is wrapped with regulatory light chain and
essential light chain
what is the function of myosin essential and regulatory light chains? what are the
4 cytoskeletons of the thick filament and their functions? label on sarcomere!
, -ELC: structural support for the neck region
-RLC: " + interacts with the MLCKinase that modifies ATPase activity
-titin: highly elastic filament that acts as scaffolding
-telethonin and myomesin: anchors titin
-myosin binding protein (MyBP-C): structural stabilizing protein with 3 isoforms (cardiac,
slow and fast twitch muscle)
what is thin filament made of? what are the supporting proteins and their
functions? label on sarcomere!
-actin G makes up actin F (double helix)
-troponin and tropomyosin: contraction
-nebulin: scaffolding
-capZ and tropomodulin: regulate the growth of actin F and stabilize filament end by
capping it
in the troponin complex, what is the function of each part?
-TnC: binds to calcium
-TnI: holds the complex and binds to actin and tropomyosin
-TnT: binds to tropomyosin
walk through how the influx of calcium into the cytosol from SR causes
contraction (end at myosin and actin binding)
COMPLETE SOLUTIONS GRADED A++
what is anatomy? what are the 3 types?
-anatomy: the study of structure and parts of living organisms
1. gross: identify and name structure
2. histology: tissue characteristics
3. functional: function
What is physiology? what are the 2 viewpoints?
-physiology: the study of functions and mechanisms of living system
1. teleological: why? (evolutionary process)
2. mechanistic: how? (cellular processes)
what are the 3 types of muscles and its special characteristic?
1. skeletal: voluntary, multinucleated, striated
2. cardiac: involuntary, uninucleated, striated with branches and intercalated disks
3. smooth: involuntary, uninucleated, not striated
what are the 3 macrostructures of muscles and what are their special
characteristic?
1. parallel (fusiform, convergent): fibers run parallel to axis of force generation. they are
FASTER bc more distance is shortened per sec since fibers are straight, not angled
2. pennate (uni, bi, multi): fibers run at angle to force generation axis. they are
,STRONGER bc more fibers per physiological cross-section
3. circular: fibers run in concentric rings and act as sphincters
what is PCSA?
-physiological cross sectional area: the cross section of a muscle PERPENDICULAR to
its fibers
structure of skeletal muscle
muscle (covered by epimysium), fascicle (perimysium), fiber (endomysium), myofibril,
sarcomere, myofilaments (thick and thin)
label a sarcomere, with bands, thick and thin filaments and their structural
proteins
-z disc to z disc: sarcomere (origin of thin filament)
-I band: only thin
-A band: entire thick, includes thin
-H band: only thick
-M line: middle of H band (origin of thick filament)
what is thick filament made of? draw the structure of it
-myosin II
-light meromyosin: alpha-helical tail + heavy meomyosin: neck and head (contains
ATPase and actin-binding domain)
-the whole molecule is heavy, but the head is wrapped with regulatory light chain and
essential light chain
what is the function of myosin essential and regulatory light chains? what are the
4 cytoskeletons of the thick filament and their functions? label on sarcomere!
, -ELC: structural support for the neck region
-RLC: " + interacts with the MLCKinase that modifies ATPase activity
-titin: highly elastic filament that acts as scaffolding
-telethonin and myomesin: anchors titin
-myosin binding protein (MyBP-C): structural stabilizing protein with 3 isoforms (cardiac,
slow and fast twitch muscle)
what is thin filament made of? what are the supporting proteins and their
functions? label on sarcomere!
-actin G makes up actin F (double helix)
-troponin and tropomyosin: contraction
-nebulin: scaffolding
-capZ and tropomodulin: regulate the growth of actin F and stabilize filament end by
capping it
in the troponin complex, what is the function of each part?
-TnC: binds to calcium
-TnI: holds the complex and binds to actin and tropomyosin
-TnT: binds to tropomyosin
walk through how the influx of calcium into the cytosol from SR causes
contraction (end at myosin and actin binding)
