embryo

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Which somites transform back into the spread form after differentiation?

Sacral (correct)
All thoracical (correct)
All cervical
Lumbar (correct)

What is the correct order of events in retinal development?

Appearance of pigment retina, neural retina & intraretinal space (1) (correct)
Closure of intraretinal space (4) (correct)
Development of n.opticus (3) (correct)
Appearance of internal & external neuroblast layer (2) (correct)

Which of the following is the first muscle to develop in the eyeball?

Common primordial of inferior rectal and oblique
Superior rectal
Medial rectal (correct)
Lateral oblique

What structure does the ear placode give rise to?

Membranous labyrinth (D) Signup and view all the answers

What does the first pharyngeal pouch develop into?

Tympanic cavity and Eustachian tube (A) Signup and view all the answers

Which of the following events occurs first in the development of the external acoustic meatus?

Development of the auricle (2) (A) Signup and view all the answers

Which of the following are components of auricular structures?

Tragus (B), Helix (C) Signup and view all the answers

What does the membrane pupillaris represent?

Remnant of posterior wall of anterior eye chamber (A) Signup and view all the answers

What is the amount of rotation for the intestinal loop in the clockwise direction?

90 degrees (C) Signup and view all the answers

Which factor is NOT involved in the development of the secondary palate?

FGF 10 (D) Signup and view all the answers

Which of the following components is NOT typically found in a pharyngeal/branchial arch?

Skin (C) Signup and view all the answers

Which two ear bones are formed from the first arch?

Malleus & Incus (A) Signup and view all the answers

From which pharyngeal/branchial arch does the tensor tympani muscle derive?

First pharyngeal/branchial arch (C) Signup and view all the answers

Which pharyngeal/branchial arch is associated with the common carotid artery?

Third (A) Signup and view all the answers

Which pharyngeal/branchial arch is associated with the facial nerve?

Second (A) Signup and view all the answers

What type of rotation occurs during herniation?

45 degrees (B) Signup and view all the answers

What develops from the dorsal primordium of the pancreas?

Accessory pancreatic duct (C) Signup and view all the answers

Which stage of lung development comes immediately after the saccular stage?

Alveolar stage (B) Signup and view all the answers

At what point during embryogenesis does the definitive oral cavity develop?

2nd month (B) Signup and view all the answers

Until which week of embryogenesis does the development of the reproductive system typically continue?

10th week (B) Signup and view all the answers

Which of the following structures contributes to the placental barrier?

Syncytiotrophoblast (C) Signup and view all the answers

Which branchial arch is the tongue primarily derived from?

1st branchial arch (A) Signup and view all the answers

Which zone is primarily responsible for the development of white matter in the brain?

Marginal zone (D) Signup and view all the answers

Which type of nerve is considered exclusively motor?

N. facialus (D) Signup and view all the answers

What is the primary source of the musculature of the tongue?

Myoblasts of the 2nd branchial arch (C) Signup and view all the answers

When do the papillae of the tongue begin to appear?

Day 50 (B) Signup and view all the answers

From which structures does the thyroid gland develop?

Epithelial proliferation between the 1st and 2nd pharyngeal pouches (B) Signup and view all the answers

Which statement about the development of the thymus is correct?

Thymus primordia derive from the endoderm. (D) Signup and view all the answers

Which branchial arch is most closely associated with the glossopharyngeal nerve?

Third pharyngeal arch (C) Signup and view all the answers

What does hyperdontia refer to?

An increased number of teeth (C) Signup and view all the answers

What is the most frequent malformation in the world?

Cleft lip (C) Signup and view all the answers

During which week does the development of the larynx, trachea, and lungs begin?

4th week (B) Signup and view all the answers

Which of the following is derived from the hindgut?

Descending colon (A) Signup and view all the answers

What is gastroschisis?

Absence of the anterior body wall with urinary anomalies. (B) Signup and view all the answers

When does the myelination process start?

4th embryonic month (A) Signup and view all the answers

Which structure does NOT contribute to the formation of the nasal cavity?

Branchial arches (D) Signup and view all the answers

What develops from the endoderm during respiratory system development?

Glands of the lower respiratory system (A) Signup and view all the answers

What is the primary influence on regional specification of the respiratory tract?

Hoxa-3 to Hoxa-5 expression (C) Signup and view all the answers

Which stage of development does the terminal alveolar sac and synthesis of surfactant occur?

Saccular stage (B) Signup and view all the answers

What role does the dorsal muscle mass play in muscle transformation?

Transforms into the flexor muscles (C) Signup and view all the answers

What are the appendix testis and utriculus prostaticus remnants of?

Ductus mesonephricus (C) Signup and view all the answers

When do nails cover the fingertips during embryogenesis?

For upper limbs until week 36, lower limbs until week 32 (B) Signup and view all the answers

From which structure do follicular cells develop?

Coelomic epithelium (B) Signup and view all the answers

What primarily happens during the mesenchymal stage of vertebral column development?

Sclerotomes differentiate and migrate (C) Signup and view all the answers

Where do secondary ossification centers for vertebrae primarily develop during the first postnatal year?

On superior and inferior surfaces (A) Signup and view all the answers

Desmal ossification is associated with which of the following skull bone types?

Both types of viscerocranium bones (A) Signup and view all the answers

When do lower limb primordials appear during embryogenesis?

Around the 28th day (B) Signup and view all the answers

At what stage does the spinal cord of the fetus reach the L1 vertebra?

9th month (D) Signup and view all the answers

What is the primary mechanism by which the epithelial seam of the palate disappears?

Fusion of palate primordial (B) Signup and view all the answers

Which event occurs last in the sequence of palatal development?

Disappearance of the epithelial seam (C) Signup and view all the answers

Gonocytes are primarily characterized as which type of cell?

Undifferentiated oval cells (C) Signup and view all the answers

What is a key factor in promoting intrauterine growth during development?

Insulin (A) Signup and view all the answers

What indicates male infertility regarding the number of spermatozoa in 1 ml of sperm?

30 million sperm (A) Signup and view all the answers

From which sources do the dermis and subcutis develop in the trunk?

From dermatome and somites in the dorsal part (D) Signup and view all the answers

Which glands are among the first to develop from skin derivatives?

Sebaceous glands and hair follicles (D) Signup and view all the answers

Somites that revert to spread form

Some somites, like cervical, thoracic, and lumbar, transition back to their original, wider state after initial differentiation.

Retinal development order - 1

Retina development starts with the formation of the internal and external neuroblast layers, then the pigment and neural retinas, and concludes with the closure of the intraretinal space.

First eye muscles

Initially, the eye's medial rectus, inferior rectus/oblique common primordium, and superior rectus muscles develop