Orbital muscles

Question 1

common characteristics in origin and insertion of all rectus extraocular muscles

Answer 1

all originate from a common annular tendon in the orbit

all insert into the sclera in front of the coronal equator of the eyeball

Question 2

common characteristic regarding the insertion of both oblique extraocular muscles

Answer 2

both insert onto the sclera on the lateral margin of the eyeball behind the coronal equator

Question 3

common characteristic concerning the insertion of the superior and inferior rectus extraocular muscles

Answer 3

insert onto the sclera of the eyeball in front of the coronal equator and are displaced slightly medially

Question 4

apparent function of the medial rectus extraocular muscle

Answer 4

pulls the cornea inward/medially: ADDuct the cornea

Question 5

apparent function of the lateral rectus extraocular muscle

Answer 5

pulls cornea outward/laterally: ABDducts the cornea

Question 6

apparent function of the superior rectus extraocular muscle

Answer 6

pulls cornea upward/superiorly and at the same time rotates the cornea inward
depression and ADDuction of the cornea
extorsion conjunct movements

Question 7

apparent function of the inferior rectus extraocular muscle

Answer 7

pulls the back to the eyeball upward and inward which causes the cornea to rotate downward and outward
depression and ABDuction of the cornea
conjunct movement of intorsion

Question 8

apparent function of the inferior oblique extraocular muscle

Answer 8

pulls the back of the eyeball downward and inward which causes the cornea to rotate upward and outward
elevation and ABDuction of cornea
conjunct movement of extorsion

Question 9

embryonic origin of the extraocular muscles or extrinsic muscles of the eyeball

Answer 9

skeletal muscle is derived from the somites hence somatic efferent (SE)

Question 10

nerves that will innervate specific extrinsic/extraocular muscles

Answer 10

oculomotor - SR, MR, IR, IO
trochlear - SO
abducens/abducent - LR