*** Hepatocytes are endodermal in origin. The liver develops from the liver bud which an outgrowth of the distal part of the endoderm of foregut. *** Heart, blood vessels, lymph vessels and the epithelial lining of these organs develop from the mesoderm.
২.
The muscular coat of the ileum develops from-
ক
Splanchnopleuric mesoderm
খ
Endoderm of the midgut
গ
Endoderm of the hindgut
ঘ
Somatopleuric mesoderm
৩.
Which is not an event of the first week of development in embryo?
ক
Formation of morula
খ
Implantation
গ
Formation of blastocyst
ঘ
Gastrulation
ব্যাখ্যা
After fertilization, important events that take place in the first week of development- 1. Cleavage 2. Formation of morula (16-cell stage) 3. Blastocyst formation 4. Migration of the zygote 5. Implantation
2nd week: Formation of bilaminar germ disc The 2nd week of development is known as the week of 2's: a) The trophoblast differentiates into 2 layers; the cytotrophoblast and syncytiotropho-blast. b) The embryoblast forms 2 layers; the epiblast and hypoblast. c) The extraembryonic mesoderm splits into 2 layers; the somatic and splanchnic layers. d) 2 cavities form; the amniotic and yolk sac cavities.
3rd week: Formation of trilaminar germ disc - Gastrulation: The process of formation of three germ layers is called gastrulation.
৪.
The notochord is formed by the cells of the –
ক
ক) Hypoblast
খ
খ) Endoderm
গ
গ) Neuroectoderm
ঘ
ঘ) Mesoderm
ব্যাখ্যা
The notochord is formed by the cells of the – Mesoderm
৫.
All are derived from the surface ectoderm, except-
ক
Anterior pituitary
খ
Enamel of teeth
গ
Dermis of skin
ঘ
Olfactory epithelium
ব্যাখ্যা
***Dermis in the head, face & neck is derived from the neural crest cells (neuroectoderm) ***Dermis is remaining parts of the body is derived from Paraxial mesoderm
৬.
The following structures are derived from endoderm :
ক
ক) parathyroid glands
খ
খ) spleen
গ
গ) pituitary gland
ঘ
ঘ) inner ear
ব্যাখ্যা
Reference-langman’s medical embryology/13th/P-86
৭.
Cartilage is derived from
ক
ক) Paraxial mesoderm
খ
খ) Intermediate mesoderm
গ
গ) Lateral plate mesoderm
ঘ
ঘ) Chorda-mesoderm
৮.
Which of the following glands is ectodermal in origin?
Neuroectoderm derivatives: 1. Neural Tube: a. Brain b. Spinal cord c. Neuron d. Neuroglia e. Ependymal cells
2. Neural Crest: a. Craniofacial bones & connective tissue b. Dermis in the face and neck c. Cranial nerve ganglia d. Spinal ganglia e. Sympathetic and pre-aortic ganglia f. Parasympathetic ganglia of GIT g. Glial cell h. Schwann cell i. C-cells of thyroid gland j. Melanocytes k. Odontoblast l. Adrenal medulla m. Leptomeninges (arachnoid & pia matter) n. Conotruncal septum in the heart
১০.
Skeletal muscle is derived from
ক
ক) Paraxial mesoderm
খ
খ) Intermediate mesoderm
গ
গ) Lateral plate mesoderm
ঘ
ঘ) Chorda-mesoderm
১১.
The process that establishes all three germ layers (ectoderm, mesoderm, and endoderm) in the embryo is called-
ক
ক) Implantation
খ
খ) Gastrulation
গ
গ) Blastomere formation
ঘ
ঘ) Embryogenesis
ব্যাখ্যা
The process that establishes all three germ layers (ectoderm, mesoderm, and endoderm) in the embryo is called- Gastrulation
১২.
Cartilage is derived from
ক
ক) Paraxial mesoderm
খ
খ) Intermediate mesoderm
গ
গ) Lateral plate mesoderm
ঘ
ঘ) Chorda-mesoderm
১৩.
Cells that form the three primitive germ layers are derived from the –
ক
ক) Epiblast
খ
খ) Cytotrophoblast
গ
গ) Hypoblast
ঘ
ঘ) Yolk sac
ব্যাখ্যা
Cells that form the three primitive germ layers are derived from the – Epiblast
১৪.
Ectodermal placodes excludes
ক
ক) Otic
খ
খ) Optic
গ
গ) Nasal
ঘ
ঘ) Lens
ব্যাখ্যা
Ectodermal placodes are focal thickenings of the cranial ectoderm that generate many different components of the sensory systems of the head. Otic, nasal & lens placodes are found.
১৫.
The structures representing all three components of embryonic disc is
ক
ক) Meninges
খ
খ) Retina
গ
গ) Tympanic membrane
ঘ
ঘ) Pituitary gland
ব্যাখ্যা
The structures representing all three components of embryonic disc is Tympanic membrane
১৬.
Which of the followings is not a neural crest derivative?
ক
Adrenal medulla
খ
Anterior pituitary
গ
Arachnoid matter
ঘ
Melanocyte
ব্যাখ্যা
Rathke's pouch and anterior pituitary develop from stomatodaeum (surface ectoderm)
১৭.
Which gland is endodermal in origin?
ক
Adrenal cortex
খ
Thyroid
গ
Lacrimal
ঘ
Parotid
১৮.
Intermediate mesoderm derivative
ক
ক) Limb bones
খ
খ) Skeletal muscle
গ
গ) Cartilage
ঘ
ঘ) Gonad
১৯.
Notochord is derived from
ক
ক) Paraxial mesoderm
খ
খ) Intermediate mesoderm
গ
গ) Lateral plate mesoderm
ঘ
ঘ) Chorda-mesoderm
২০.
All three primary germ layers are derived from the-
ক
Hypoblast
খ
Cytotrophoblast
গ
Epiblast
ঘ
Syncytotrophoblast
ব্যাখ্যা
According to the current concept, all the three primary germ layers are derived from epiblast.
২১.
Mesoderm showing segmentation is -
ক
ক) Intermediate
খ
খ) Paraxial
গ
গ) Lateral plate
ঘ
ঘ) Splanchnic mesoderm
ব্যাখ্যা
Mesoderm showing segmentation is - Paraxial
২২.
Melanocytes develop from-
ক
Epidermis
খ
Lateral plate mesoderm
গ
Neural crest
ঘ
Dermis
২৩.
Which is not a derivative of the neural crest cells?
ক
Autonomic ganglia
খ
Adrenal medulla
গ
Anterior pituitary
ঘ
Pia matter
ব্যাখ্যা
*** Anterior pituitary develops from Ratke's pouch which is a diverticulum from the stomatodaeum (Surface ectoderm).
২৪.
Cornea is derived from
ক
ক) Surface ectoderm
খ
খ) Neural crest
গ
গ) Neural tube
ঘ
ঘ) Endoderm
২৫.
Which is a derivative of the neural crest cells?
ক
Anterior horn cells
খ
Dura matter
গ
Spinal ganglia
ঘ
Adrenal cortex
২৬.
Anal canal below the pectinate line develops from-