Carnegie stage 14

Introduction

Facts

Week 5, 31 - 35 days, 5 - 7 mm

View: Lateral view. Amniotic membrane removed.

Events

Ectoderm: sensory placodes, lens pit, otocyst, nasal placode, primary/secondary vesicles, fourth ventricle of brain,

Mesoderm: continued segmentation of paraxial mesoderm (more than 30 somite pairs), heart prominence

Head: 1st, 2nd and 3rd pharyngeal arch, forebrain, site of lens placode, site of otic placode, stomodeum

Body: heart, liver, umbilical cord, mesonephric ridge

Limb: upper and lower limb buds

Features

midbrain, nasal placode, lens pit, 1,2,3 pharyngeal arches, fourth ventricle of brain, 1st pharyngeal groove, heart prominence, cervical sinus, upper limb bud, mesonephric ridge, lower limb bud, umbilical cord

Identify: midbrain region, nasal placode, lens pit, 1st, 2nd and 3rd pharyngeal arches, 1st pharyngeal groove, maxillary and mandibular components of 1st pharyngeal arch, fourth ventricle of brain, heart prominence, cervical sinus, upper limb bud, mesonephric ridge, lower limb bud, umbilical cord

Image source: Embryology page Created: 19.03.1999