The Muscular System

Question 1

How many muscles in human body and what mass they make up on average

Answer 1

over 600 and make about half of our mass

Question 2

types of muscle in body

Answer 2

skeletal or striated
cardiac
smooth

Question 3

four functions of skeletal muscle

Answer 3

generate power through converting ATP
maintain posture and balance
stabilise joints
produce heat

Question 4

hierarchal orientation of skeletal muscle (from largest to smallest)

Answer 4

muscle
fascicle
fibre
myofibrils
sarcomeres

Question 5

what does skeletal muscle have that not all cardiac an smooth muscle does

Answer 5

a nerve (to receive and send information)
artery and vein (deliver blood, oxygen, nutrients and export CO2 and other waste)

Question 6

3 level of connective tissue for skeletal muscle

Answer 6

epimysium - dense irregular connective tissue, surrounding whole muscle and might fuse with fascia

perimysium - fibrous dense connective tissue surrounding fascicles

endomysium - fine areolar connective tissue surrounding each muscle fibre

Question 7

how do muscle attach to skeleton and in at least how many places

Answer 7

attachments are either direct or indirect
direct - (fleshy) where epimysium is fused to periosteum of bone or perichondrium of cartilage
indirect - connective issue extend beyond muscle as tendon (long Achilles) or sheet-like aponeurosis

in at least two places - origin (more fixed and proximal) and insertion (movable and distal)

Question 8

difference between tendon and aponeurosis (structure and function wise)

Answer 8

tenon is rope like bands (jut muscle to bone)
aponeurosis are sheet-like dense regular connective tissues (like parchment paper) can connect muscle to muscle, bone or fascia

Question 9

functional groups n muscle interactions

Answer 9

agonist (primer mover)
antagonist (located on opposite side of agonist)
synergist (helps agonist by doing additional movement and power)

Question 10

Based on what features can muscles be named

Answer 10

location of muscle (bone or body region) and
attachments (always name site of origin first)
shape of muscle
size of muscle
number of origins (eg. Bicep tricep)
muscle action (flexor eg.)
direction of muscle fibres (rectus - up and down, transversus - to the side, oblique - at an angle)

Question 11

types of muscle arrangement

Answer 11

parallel - fascicles lie parallel to muscle line of action
pennate - fascicles at angle relative to line of action
circular - muscle fibres in a ring

Question 12

types of parallel muscle arrangements

Answer 12

either strap (long parallel fibres with broad sheet like tendons at proximal and distal tendons) or fusiform (forms circular like shape eg bicep)

Question 13

types of pennate muscle arrangements

Answer 13

uni pennate - all fibres follow same direction
bi pennate - two dir
multi pennate - many dir

Question 14

in what way does a pennate muscle structure effect the function of that muscle

Answer 14

pennate muscles have short and angled fibres which means the ROM is decreased
however more packed fibres means more power
have higher PCSA (physiological cross section area - more fibres within a given volume)

Question 15

in what way does a parallel muscle structure effect the function of that muscle

Answer 15

longer but less dense

larger ROM lower PCSR

Question 16

what is a power leaver (or mechanical advantage)

Answer 16

load is close to fulcrum (axis of rotation), small effort can move large load

Question 17

what is a speed ever (or mechanical disadvantage)

Answer 17

load far from fulcrum, offering wide range of motion but harder to lift

Question 18

Muscle in head

Answer 18

temporalis

masseter

Question 19

muscles in shoulder

Answer 19

trapezius

deltoid

Question 20

muscles in thorax

Answer 20

pectoralis major
serratus anterior
intercostals

Question 21

muscles in arm

Answer 21

triceps brachii

biceps brachii

Question 22

abdominal muscles

Answer 22

rectus abdominis
external and internal obliques
transversus abdominis
external and internal intercostals

Question 23

muscles in anterior thigh (quads)

Answer 23

rectos femoris
vastus lateralis
vastus medialis
Vastus intermedius

Question 24

muscles in lower leg (anterior shin)

Answer 24

tibialis anterior

Question 25

muscles in shoulder (posterior)

Answer 25

deltoid

letissimus dorsi

Question 26

muscles in hip (posterior glutes)

Answer 26

gluteus max, med, min

Question 27

muscles in posterior thigh (hamsting)

Answer 27

bicep femoris
semitendinosus
semimembranosus

Question 28

muscles in posterior leg (calf)

Answer 28

gastrocnemius (medial and lateral)
soleus (lateral)
Achilles tendon (not a muscle but she included it) all listed muscles above connect to it

Question 29

key functions of abdominal and thorax muscles

Answer 29

support and protect visceral organs
set of obliques as well as rectus and transverse abdomens enable flexion of trunk, lateral flexion and rotation

external intercostals are inspiratory muscles (forced inhalation)
internal intercostals and rectus abdominis are for forced exhalation

Question 30

functions of anterior and posterior arm muscles

Answer 30

posterior - deltoid abducts arm
latissimus dorsi (back) extends and adducts arm

anterior
pectoralis major adducts
tricep brachii extends forearm
bicep brachii flexes it about the elbow joint

Question 31

common shoulder injury

Answer 31

rotator cuff injury - rotator cuff is comprised of supraspinatus, infraspinatus, subscapularies and teres minor

can be acute (from a one time incident) or chronic (from repetitive use of shoulder)
can lead to dislocation and tendinitis (inflammation and damage of these joints)

Question 32

anterior thigh function

Answer 32

to extend the knee

Question 33

where is the IT band and what’s its full name

Answer 33

Iliotibial tract