LBOBI19 LE 2 LATEST UPDATE 2026/2027 EXAM
QUESTIONS AND ANSWERS
(33-hr) At the caudal end, the converging bands represent the _ -ANSWER -
Primitive ridges/folds
(33-hr) The lateral margins of the primitive streak -ANSWER -Primitive
ridges/folds
(33-hr) The site of mesoderm formation at this stage -ANSWER -Primitive streak
(33-hr) The two largest evaginations of the neural tube -ANSWER -Optic vesicles
(33-hr) The earliest rudiments of the eyes -ANSWER -Optic vesicles (33-hr) The
optic vesicles evaginate from which region of the brain? -ANSWER
Diencephalon
(33-hr) The optic vesicles are in close contact laterally with the overlying _ -
ANSWER -Skin ectoderm
(T/F) (33-hr) The regions of skin ectoderm near the optic vesicles are thickened -
ANSWER -False; Probably not thickened
(33-hr) The regions of skin ectoderm near the optic vesicles will later thicken and
transform into the _ of the eyes -ANSWER Lenses
,(33-
hr) The dark, shadowy mass in the midline
between the optic vesicles which evaginates from the floor of the _ - CORRECT
ANSWERInfundibulum; Diencephalon
(33-hr) The infundibulum will later form the _ -ANSWER -Posterior pituitary
gland/Neurohypophysis
(33-hr) AKA posterior pituitary gland -
CORRECT ANSWER-Neurohypophysis
(33-hr) Level of the brain cranial to the diencephalon -ANSWER Telencephalon
(33-hr) The telencephalon and diencephalon are not clearly distinguishable at this
stage and are thus referred to collectively -ANSWER -True
(33-hr) The collective name for telencephalon + diencephalon -ANSWER
Prosencephalon
(33-hr) The white median notch/cleft in the telencephalon -ANSWER -Remnant
of the cranial/anterior neuropore
(T/F) (33-hr) At this stage, the neural folds that originally flanked the cranial
neuropore are completely fused -ANSWER -
False; approximated only, not yet completely fused hr) The brain region caudal to
the diencephalon is the (1), followed by the (2) -
CORRECT ANSWER-(1) Mesencephalon
, (2) Metencephalon
(33-
(33-hr) Order of brain regions from most anterior to most posterior - CORRECT
ANSWER-
Telencephalon > Diencephalon >
Mesencephalon > Metencephalon >
Myelencephalon
(33-hr) The most caudal brain region that is characterised by several smaller
enlargements of the neural tube -ANSWER Myelencephalon
QUESTIONS AND ANSWERS
(33-hr) At the caudal end, the converging bands represent the _ -ANSWER -
Primitive ridges/folds
(33-hr) The lateral margins of the primitive streak -ANSWER -Primitive
ridges/folds
(33-hr) The site of mesoderm formation at this stage -ANSWER -Primitive streak
(33-hr) The two largest evaginations of the neural tube -ANSWER -Optic vesicles
(33-hr) The earliest rudiments of the eyes -ANSWER -Optic vesicles (33-hr) The
optic vesicles evaginate from which region of the brain? -ANSWER
Diencephalon
(33-hr) The optic vesicles are in close contact laterally with the overlying _ -
ANSWER -Skin ectoderm
(T/F) (33-hr) The regions of skin ectoderm near the optic vesicles are thickened -
ANSWER -False; Probably not thickened
(33-hr) The regions of skin ectoderm near the optic vesicles will later thicken and
transform into the _ of the eyes -ANSWER Lenses
,(33-
hr) The dark, shadowy mass in the midline
between the optic vesicles which evaginates from the floor of the _ - CORRECT
ANSWERInfundibulum; Diencephalon
(33-hr) The infundibulum will later form the _ -ANSWER -Posterior pituitary
gland/Neurohypophysis
(33-hr) AKA posterior pituitary gland -
CORRECT ANSWER-Neurohypophysis
(33-hr) Level of the brain cranial to the diencephalon -ANSWER Telencephalon
(33-hr) The telencephalon and diencephalon are not clearly distinguishable at this
stage and are thus referred to collectively -ANSWER -True
(33-hr) The collective name for telencephalon + diencephalon -ANSWER
Prosencephalon
(33-hr) The white median notch/cleft in the telencephalon -ANSWER -Remnant
of the cranial/anterior neuropore
(T/F) (33-hr) At this stage, the neural folds that originally flanked the cranial
neuropore are completely fused -ANSWER -
False; approximated only, not yet completely fused hr) The brain region caudal to
the diencephalon is the (1), followed by the (2) -
CORRECT ANSWER-(1) Mesencephalon
, (2) Metencephalon
(33-
(33-hr) Order of brain regions from most anterior to most posterior - CORRECT
ANSWER-
Telencephalon > Diencephalon >
Mesencephalon > Metencephalon >
Myelencephalon
(33-hr) The most caudal brain region that is characterised by several smaller
enlargements of the neural tube -ANSWER Myelencephalon
