Histology - Germ Layer Development and Tissue
Organization Exam With complete solution–Expert Verified |
Latest Questions 2025
Treacher-Collins syndrome - Bilateral underdevelopment of maxillary, mandibular, and
facial bones
Zygote - Totipotent cell capable of forming embryonic and extraembryonic cells
Totipotent - Able to form any human cell (zygote)
What does the zygote proliferate into - Embryonic and extra-embryonic cells
What are stem cells - Immature (undifferentiated) cells that are classified based on
potency to give rise to different cells
Pluripotent - Able to differentiate into most cells, but not all (ESCs)
Multipotent - able to differentiate into some cells
Unipotent - Able to differentiate into one cell type
Nullipotent - terminally differentiated (RBC)
Properties of stem cells - Capable of self-renewal
Can give rise to progenitor cells that give rise to nullipotent or unipotent cells
Endoderm - migrated through midline opening forms inside cell layer of embryo.
mesoderm - migrated and formed to the tissue in the middle layer of the body
What germ layer do stem cells give rise to - All three (ectoderm, endoderm and
mesoderm)
Adult stem cells - Multipotent and tissue specific to maintain and replace worn-out cells
What type of stem cells are embryonic stem cells - pluripotent
Term for the differentiation of ESCs into the germ layers - Gastrulation
Gastrulation - The migration of most cells from the surface through a midline surface
opening into the internal part of the embryo
, Ectoderm initial position - Cells remain on outer surface during gastrulation
Mesoderm initial position - migrated through the midline to form the middle of the
embryo
Endoderm initial position - Cells differentiate to form the middle of the embryo
Endoderm derivatives in adults - Epithelial cells from tissue membranes that line the
inside of hollow organs and endocrine/exocrine glands
Mesoderm derivatives in adults - CT, cartilage, bones, synovial membranes
Muscle (cardiac, smooth, and skeletal)
RBC/WBC
epithelium of serous membranes and lining lumen of vessels
Ectoderm derivatives in adults - Epithelial of skin
Mucous membranes of luminal surface of passageways/cavities that remain in contact
with outside world (oral, nasal)
Forms neuroectoderm and neural crest
Neuroectoderm derivatives in adults - Neural tissue in CNS and spinal cord
Neurulation - Inductive signaling leads to formation of NC and NE from ectoderm to
form CNS and PNS
Notochord - Initial inducer
Signals mesoderm to form neural plate
Becomes the nuclei pulposus
What does the notochord form - Vertebral column (intervertebral discs and vertebrae)
What tissues come from the neuroectoderm - Nervous cell bodies and fibers, epithelium
lining ventricles, central canal, and CT meninges of brain/spinal cord
Neuroepithelium - Neruoectoderm derived epithelium that lines the inside of ventricles
of the brain
What tissues come from the neural crest - Melanocytes, nervous tissue of PNS
(ganglia/neurons), and neural crest-derived mesoderm that form facial bones
Ectomesenchyme - Neural crest-derived mesoderm (forms facial bones)
Identify the Germ Layer: skin - ectoderm
Identify the Germ Layer: hair - ectoderm
Organization Exam With complete solution–Expert Verified |
Latest Questions 2025
Treacher-Collins syndrome - Bilateral underdevelopment of maxillary, mandibular, and
facial bones
Zygote - Totipotent cell capable of forming embryonic and extraembryonic cells
Totipotent - Able to form any human cell (zygote)
What does the zygote proliferate into - Embryonic and extra-embryonic cells
What are stem cells - Immature (undifferentiated) cells that are classified based on
potency to give rise to different cells
Pluripotent - Able to differentiate into most cells, but not all (ESCs)
Multipotent - able to differentiate into some cells
Unipotent - Able to differentiate into one cell type
Nullipotent - terminally differentiated (RBC)
Properties of stem cells - Capable of self-renewal
Can give rise to progenitor cells that give rise to nullipotent or unipotent cells
Endoderm - migrated through midline opening forms inside cell layer of embryo.
mesoderm - migrated and formed to the tissue in the middle layer of the body
What germ layer do stem cells give rise to - All three (ectoderm, endoderm and
mesoderm)
Adult stem cells - Multipotent and tissue specific to maintain and replace worn-out cells
What type of stem cells are embryonic stem cells - pluripotent
Term for the differentiation of ESCs into the germ layers - Gastrulation
Gastrulation - The migration of most cells from the surface through a midline surface
opening into the internal part of the embryo
, Ectoderm initial position - Cells remain on outer surface during gastrulation
Mesoderm initial position - migrated through the midline to form the middle of the
embryo
Endoderm initial position - Cells differentiate to form the middle of the embryo
Endoderm derivatives in adults - Epithelial cells from tissue membranes that line the
inside of hollow organs and endocrine/exocrine glands
Mesoderm derivatives in adults - CT, cartilage, bones, synovial membranes
Muscle (cardiac, smooth, and skeletal)
RBC/WBC
epithelium of serous membranes and lining lumen of vessels
Ectoderm derivatives in adults - Epithelial of skin
Mucous membranes of luminal surface of passageways/cavities that remain in contact
with outside world (oral, nasal)
Forms neuroectoderm and neural crest
Neuroectoderm derivatives in adults - Neural tissue in CNS and spinal cord
Neurulation - Inductive signaling leads to formation of NC and NE from ectoderm to
form CNS and PNS
Notochord - Initial inducer
Signals mesoderm to form neural plate
Becomes the nuclei pulposus
What does the notochord form - Vertebral column (intervertebral discs and vertebrae)
What tissues come from the neuroectoderm - Nervous cell bodies and fibers, epithelium
lining ventricles, central canal, and CT meninges of brain/spinal cord
Neuroepithelium - Neruoectoderm derived epithelium that lines the inside of ventricles
of the brain
What tissues come from the neural crest - Melanocytes, nervous tissue of PNS
(ganglia/neurons), and neural crest-derived mesoderm that form facial bones
Ectomesenchyme - Neural crest-derived mesoderm (forms facial bones)
Identify the Germ Layer: skin - ectoderm
Identify the Germ Layer: hair - ectoderm
