8 Week

Embryo At 8+ Week(Carnegie Stage 20)
Week 8, 51 - 53 days, 18 - 22 mm
Features: Scalp vascular plexus, eylid, eye, nose, external acoustic meatus, auricle of external ear, arm, elbow, wrist, liver prominence, digital rays.
Identify: straightening of trunk, pigmented eye, eyelid, nose, external acoustic meatus, scalp vascular plexus, digital rays, liver prominance, thigh, ankle, foot plate, umbilical cord.
Events: Ectoderm: sensory placodes, lens pit, otocyst, nasal pits moved ventrally, fourth ventricle of brain
Mesoderm: heart prominence, ossification continues
Head: forebrain, eye, external acoustic meatus.
Body:straightening of trunk, heart, liver, umbilical cord.
Limb: upper limbs longer and bent at elbow, foot plate with digital rays, wrist, hand plate digital rays begin to separate.