Embryology Flashcards
1
Q
The pharyngeal arches, pharyngeal pouches, pharyngeal cleft, and pharyngeal membrane all make up the ?
A
Pharyngeal apparatus
2
Q
The pharyngeal apparatus contributes to the formation of what and what regions of the body?
A
The Head and Neck regions
3
Q
The development of the pharyngeal apparatus begins in what week of Intra-Uterine Development
A
4th week
4
Q
The pharyngeal apparatus develops from the?
A
Primitive pharynx caudal
5
Q
Folds/elevations on the lateral wall of the primitive pharynx caudal is called
A
The pharyngeal apparatus
6
Q
The inner spaces between the pharyngeal arches are called?
A
Pharyngeal pouches
7
Q
The grooves on the outer pharyngeal wall are called?
A
Pharyngeal cleft
8
Q
The first artery of the pharyngeal arch becomes the?
A
Maxillary artery
9
Q
The second artery of the pharyngeal arch becomes?
A
Hyoid and stapedial arteries
10
Q
The third artery of the pharyngeal arch becomes?
A
- Common carotid artery
- Internal carotid artery
11
Q
The fourth artery of the pharyngeal arch becomes?
A
- Aortic arch
- Subclavian artery
12
Q
The sixth artery of the pharyngeal arch becomes?
A
- Ductus arteriosus
- Pulmonary artery
13
Q
The first arch cartilage of the pharyngeal arch is called?
A
Meckel’s cartilage
14
Q
The second cartilage of the pharyngeal arch is called?
A
Richerts cartilages
15
Q
The Merkel’s cartilage forms?
A
The malleus and incus of the middle ear
16
Q
Reichert’s cartilage forms?
A
The stapes bone in middle ear, and body of hyoid bone
17
Q
The 4th and 6th cartilages form ?
A
The thyroid, cuneiform, corniculate, arytenoid, and cricoid cartilages
18
Q
The 1st Arch nerve is also called?
A
Trigeminal nerve
19
Q
What embryonic nerve supplies the taste fibres and the anterior ⅔ of the tongue
A
The chorda tympani
20
Q
The 2nd arch nerve is also called
A
Facial nerve
21
Q
The facial nerve supplies?
A
All muscles derived from the second arch
22
Q
The 3rd arch nerve is also called?
A
Glossopharyngeal nerve
23
Q
The 4th arch nerve is also called?
A
The superior laryngeal nerve
24
Q
The 6th arch nerve is also called?
A
The recurrent laryngeal nerve
25
The 1st arch muscle forms the ?
Muscle of mastication
26
The 2nd arch muscle forms the?
Muscle of facial expression, and posterior belly of digastric
27
The only muscle derived from 3rd arch is the?
Stylopharyngeus
28
The cricothyroid, levator veli palati, constrictors of the pharynx are muscles derived from the?
4th arch cartilage
29
The intrinsic muscles of the larynx is derived from the?
Sixth arch
30
The distal part of the tubotympanic recess becomes ?
The middle ear cavity and mastoid Air cells
31
The first pharyngeal pouch elongates to form a diverticulum known as?
Tubotympanic recess
32
The proximal tubular part of the pharyngeal pouch forms the?
Eustachian / auditory tube connecting the nasopharynx and middle ear
33
The 2nd pharyngeal pouch form tiny solid buds that develop into?
palatine tonsils
34
The ventral tubular part forms ?
the thymus
35
The 4th pharyngeal pouch forms?
Parathyroid gland
36
The external auditory meatus(ear canal) is formed from
The 1st pharyngeal cleft
37
Clinical correlations of the pharyngeal cleft
1. Brachial cyst & Fistula
2. First arch syndromes
38
Examples of the defects to the 1st arch include;
Trecher Collins syndrome
Pierre-robin syndrome
Digeorge
39
______ is unique to each person, and is the basis for identity?
Face
40
Abnormalities to congenital development are caused by
Teratogen
41
The face forms from?
Oropharyngeal membrane
42
The face developed from what embryonic tissues?
All 3 embryonic tissues (Ectoderm, mesoderm and endoderm)
43
The fronto-nasal process rises from?
Neural crest
44
A plate-like thickening of the epithelial layer of an embryo which develops into a sense organ is called
A placode
45
At week 10, inter-maxillary process forms?
The nasal bridge and the philtrum of upper lip
46
The tissues of the 1st pharyngeal arch originates from?
Mesoderm and neural crest
47
Nasal placodes appear at week 4 and are the precursor to the olfactory epithelium.
True or False
True
48
The fusion of _____ and _____ results in formation of philtrum of upper lip?
1. Maxillary processes
2. Medial nasal process
49
Mention 2 events that take place in week 5 of facial development
1. The oropharyngeal membrane disintegrates leaving behind a communication between the digestive tract and external environments
2. The eyes which are initially located at the side of the head, face forward as the head grows
50
At what week will the embryo have human appearance?
7th week
51
The upper part of the mouth that separate the nasal and oral cavity is called?
Palate
52
The opening towards the back of the nasal cavity that connects the oral and nasal cavities is called
Choana
53
Embryologically, the primary palate gives rise to?
Anterior ⅓ from the incisive cleaned and upper 4 incisors
54
Embryologically, the secondary palate gives rise to?
Hard palate and soft palate
55
Development of the palate takes place in what week?
7th - 8th week
56
2 significant mechanisms that can cause a cleft palate include?
1. Growth retardation
2. Mechanical obstruction
57
_________ and _________ are congenital clinical implications related to development of palate and nasal septum.
1. Cleft lip/palate
2. Choanal atresia
58
Loosely organized cells derived from mesodermal embryonic tissues, that later develop into connective tissue and skeletal tissues. Are called?
Mesenchyme
59
Mention 4 things the inter-maxillary segment, gives rise to?
1. Bridge of nose
2. Philtrum
3. 4 upper incisors
4. Primary palate
60
The structures of the oral cavity derive from?
First branchial arch
61
Which pharyngeal arch (es) contribute to the development of different parts of the tongue
1st, 2nd, 3rd, and 4th pharyngeal arches
62
Development of the tongue begins with growth of medial swelling From 1st pharyngeal arch known as?
Tuberculum Impar
63
The tuberculum impar, together with 2 lateral lingual swelling which fuse and overlap the tuberculum impar, form?
The anterior ⅔ of the tongue
64
The anterior ⅔ of the tongue is innervated by?
Chorda tympani
65
The hypobranchial eminence forms what part of the tongue?
The posterior ⅔ of the tongue
66
The posterior ⅔ of the tongue is innervated by?
Glossopharyngeal nerve
67
The most posterior part of the tongue is formed from the 4th pharyngeal arch, and This part is innervated by?
Superior laryngeal nerve
68
The muscle of the tongue derive from the myoblast which originate in?
Occipital somites
69
The muscles of the tongue are innervated by?
Hypoglossal nerve
70
The muscles of the tongue are classified in 2, name them?
1. Extrinsic muscles
2. Intrinsic muscles
71
Examples of extrinsic muscles of the tongue, include?
1. Genioglossus
2. Palaglossus
3. Hyoglossus
4. Styloglossus
Mnemonic: Great P.H.S
72
What is the action of Extrinsic muscles of the tongue?
They allow the tongue move in all directions
73
Extrinsic muscles of the tongue have their origin where?
Structures adjacent to the tongue
74
Examples of intrinsic muscles of the tongue?
1. Verticalis
2. Superior longitudinal
3. Inferior longitudinal
4. Transverses muscles
Mnemonic: V.SIT
75
Intrinsic muscles all have their origin and insertion where?
Inside the tongue
76
The intrinsic muscles of the tongue are responsible for what action?
Changing the shape
of the tongue
77
Development of taste buds on the lingual epithelium begins at?
Week 8 of IUL
78
Primordial taste buds differentiate into different cell types at?
11th - 13th week
79
Mention the functions of the tongue
1. Taste function
2. Speech
3. Food manipulation (aids digestion)
80
The respiratory system, including the lining epithelium of the larynx,trachea, bronchi and lungs originates from?
Endodermal layer
81
The respiratory diverticulum develops from
A ventral outgrowth of the cranial part of the foregut
82
The respiratory diverticulum begins as a midline groove, but it later deepens form?
Laryngo-tracheal diverticulum
83
The proximal part of the laryngo-tracheal diverticulum forms?
Larynx and Trachea
84
The distal part of the laryngo-tracheal diverticulum bifurcates into
2 Bronchial /Lung buds
85
The trachea develops from?
Laryngo-tracheal diverticulum
86
Epithelium and gland of trachea develop from?
Endoderm
87
Cartilage, muscle and connective tissues of the respiratory system are derived from?
Splanchnic mesoderm
around laryngo-tracheal groove
88
Each lungs consist of _____ bronchopulmonary segments
10
89
Mention 2 congenital defects related to bronchi and lungs
1. Tracheoesophageal fistula
2. Tracheal sternosis
90
The stages of lung maturation are?
1. Pseudoglandular stage
2. Canalicular stage
3. Terminal sac
4. Alveolar stage
91
The pseudoglandular stage ranges from?
Week 5 to 16
92
The canalicular stage ranges from?
Week 16 to 26
93
The terminal sac (saccular) stage ranges from?
Week 26 to birth
94
The alveolar stage ranges from?
8 months to 8 years
95
Examples of developmental changes that take place in the pseudoglandular stage include;
1. Formation of Bronchial tree
2. Differentiation of airway epithelium
3. Development of Smooth muscle
96
Production of surfactant begins at what week?
24th week
97
A child, born at the end of the canalicular stage could survive.
True or False
True
98
Importance of surfactant include;
1. Prevents lungs from collapse by reducing surface tension
2. Improves lungs compliance
3. Prevents atelectasis
99
Fetal Breathing Movement starts before birth.
True or False
True
100
Mention factors that affect lung development?
1. Adequate thoracic space
2. Fetal Breathing movements
3. Adequate volume of amniotic fluid
4. Vascular development and blood supply
101
For medicolegal purposes, the lungs of a still born and live born baby can be differentiated by?
Placing in the lungs in water, the still born lungs would sink, and
The live born lungs would float due to presence of air inside the lungs
102
______ is caused by surfactant deficiency
Respiratory Distress Syndrome
103
Respiratory Distress Syndrome is treated by use of?
Corticosteroids and thyroxine
104
Failure of the cranial neuropore to close leads to?
Anencephaly
105
Failure of the caudal neuropore to close leads to?
Spina bifida
106
Both the urinary and genital systems develop from?
Intermediate mesoderm
107
In IUD of the kidney, there are 3 systems, namely?
1. Pronephros
2. Mesonephros
3. Metanephros
108
_____ is the rudimentary and non-functional kidney system in IUD?
Pronephros
109
______ forms the permanent kidney?
Metanephros
110
In males, ______ ducts persist and participate in the formation of the genital system .
Mesonephric
111
The collecting ducts of the permanent kidney develop from?
Ureteric buds
112
Ureteric buds give rise to; _______, _______, _______ and ________
1. Ureter
2. Renal pelvis
3. Major and minor calyces
4. 1 to 3 million collecting tubules
113
The excretory units of the kidney develop from?
Metanephric mesoderm
114
Continuous lengthening of the excretory tubule results in formation of?
1. Proximal convoluted tubule
2. Loop of henle
3. Distal convoluted tubule
115
At birth, there are approximately ______ nephrons in each kidney?
1 million
116
Following the differentiation of glomerular capillaries, urine production begins at what week?
10th week
117
Every newly formed collecting tubule is covered at its distal end by a?
Metanephric tissue cap
118
The ascent of the kidney is caused by?
Diminution of body curvature and growth of body in lumbar and sacral regions
119
Clinical abnormalities in location of kidney include;
1. Pelvic kidney
2. Horse shoe kidney
3. Accessory renal arteries
120
The definitive kidney is formed from the metanephros at?
Week 12
121
Urine in IUL is removed via
It passes into amniotic cavity and mixes with amniotic fluid
122
In fetal life, the kidneys are not responsible for excretion of waste products. Rather the ________ serves this function?
Placenta
123
Within the 4th-7th week of IUD, the cloaca divides into?
1. Urogenital sinus
2. Anal canal
124
A septum between the urogenital sinus and anal canal is called?
Urorectal septum
125
The tip of the urorectal septum will form?
Perineal body
126
_____ is a fetal structure that is later obliterated
Allantois
127
The urogenital sinus has 3 parts, namely?
1. Urinary bladder
2. Pelvic part
3. Phallic part
128
In males, the definitive urogenital sinus develops into?
Penile urethra
129
In males, the ejaculatory ducts are formed from?
The mesonephric ducts
130
_________ is formed by buds from the urethra
Prostate gland
131
_________ is formed by budding from the ductus deferens
Seminal vesicles
132
The epithelium of the urethra in both males and females originate from?
The endoderm
133
In females, the cranial part of the urethra gives rise to?
Urethral and Para-urethral glands
134
_______ is the part of the mesoderm of an embryo that develops into a connective tissue, bone or cartilage
Mesenchyme
135
Example of bladder defects are;
1. Urachal fistula
2. Urachal cyst
3. Urachal sinus
4. Exstrophy of the bladder
5. Exstrophy of the cloaca
136
The nervous system is derived from what embryonic layer?
Ectoderm
137
______, ______ and ______ make up the Brainstem (hind brain)?
Pons, Cerebellum and Medulla oblongata
138
The development of the nervous system behind at what week?
3rd week.
It begins with neurulation
139
The brain and the spinal cord is covered by 3 meninges, namely?
Pia, Arachnoid, and Dura matter
140
______ stimulates growth factors and neuroectodermal induction?
The Notochord
141
Cellular condensation of the neutral plate leads to formation of ______, _______ and then ______
Neural groove,
Neural fold,
then the Neural tube
142
Cells that migrate to the top before formation of the neutral tube are called?
Neural crest cells
143
Neural crest cells form what part of the nervous system?
Peripheral nervous system
144
Cells within the neural tube form what part of the nervous system?
Central nervous system
145
Closure of the rostral neuropore takes place by?
Day 25
146
Closure of the caudal neuropore, takes place by?
Day 26-28
(About 2 days after closure of cranial neuropore)
147
The primary vesicles appear at?
They include?
4th week
They are; Prosencephalon, Mesencephalon, Rhombencephalon
148
The opening around the junction of the medulla and spinal cord at the level of vertebrae C1, is called?
Foramen magnum
149
______ are the passage ways for CSF in the brain?
Ventricles
150
Ependymal cells are found within the _______ of the brain?
Ventricles
151
The foramen between the 2 lateral ventricles, is called?
Foramen of Monroe
152
The failure of the rostral neuropore to close by day 25 results in?
Anencephaly
153
The failure of the caudal neuropore to close by the 28th day would result in?
Spina bifida
154
At the 5th week, the prosencephalon divided to form _______ and ______?
1. Telencephalon
2. Diencephalon
155
At the 5th week, the Rhombencephalon divides to form _______ and ______?
1. Metencephalon
2. Myelencephalon
156
The Mesencephalon doesn't divide, it just develops to form?
The Midbrain
157
The Telencephalon forms?
The Cerebrum (cerebral cortex and cerebral hemispheres)
158
The Diencephalon forms?
1. Thalamus
2. Hypothalamus
3. Sub thalamic
159
The Diencephalon forms?
1. Thalamus
2. Hypothalamus
3. Sub thalamic
160
_______ is caused by inflammation of the Dura matter?
Head aches
