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Embryology > Skeletal system > Flashcards

Skeletal system Flashcards

1
Q

When do the notochord and the neural tube form

A

3rd week

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2
Q

As the notochord and neural tube form int he third week, the __ ___ lateral to these structures thickens to form two longitudinal columns of ___ ___

A

Intraembryonic mesoderm

Paraxial mesoderm

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3
Q

Toward the end of the third week, these columns located in the trunk, become segmented into blocks of mesoderm-__

A

Somites

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4
Q

Externally he somites appear as a bead like elevations along the dorsolateral surface of the embryo. Each somite differentiate into two parts:

A

The ventromedial part is sclerotome

The dorsolateral part is the dermomyotome

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5
Q

Sclerotome

A

Cells form the vertebrae and rise

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6
Q

Dermomyotome

A

Cells from its myotome region form myoblasts and those from its dermatome region form dermis

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7
Q

Cartilage develops from mesenchyme during the _ week

A

Fifth

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8
Q

In areas where cartilage is to develop, the mesenchyme condenses to form __ __

A

Chondrification centers

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9
Q

The mesenchymal cells differentiate into __, which secrete collagenous fibrils and extracellular matrix

A

Chrondroblasts

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10
Q

Subsequently, collagenous and or elastic fibers are deposited int he intercellular substance or __

A

Matrix

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11
Q

Three types of cartilage in matrix

A

Hyaline
Fibrocartilage
Elastic

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12
Q

Hyaline cartilage

A

Most widely distributed type in synovial joints

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13
Q

Fibrocartilage

A

IV discs

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14
Q

Elastic cartilage

A

In auricle of the external ears

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15
Q

Bone develops primarily in two types of CT, ___ and ___, but it can also develop in other CT(patella develops ina. Tendon)

A

Mesenchyme

Cartilage

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16
Q

Intramembranous bone formation

A

Flat bones develop in mesenchyme within preexisting membranous sheaths

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17
Q

Endochondral bone formation

A

Mesenchymal models of most limb bones are transformed into cartilaginous bone models, which later become ossified

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18
Q

Like cartilage, bone consists of cells and an organic intercellular substance-__ __, which comprises collagen fibrils embedded in an amorphous component

A

Bone matrix

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19
Q

Osteogenesis and chondrogenesis are programmed early in development , and are independent processes under the influence of ____ ___

A

Vascular events

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20
Q

What signaling molecules have been implicated as endogenous regulators of chondrogenesis and skeletal development

A

The hox genes, bmp 5, 7 and growth differentiation factors 5-members of the tgfb superfamily

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21
Q

In intramembranous ossification, the mesenchyme condenses and becomes highly ___; some cells differentiate into ____ and begin to deposit unmineralized matrix-__ ___

A

Vascular
Osteoblasts
Osteoid

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22
Q

__ signaling is a key factor in osteoblast differentiation

A

Wnt

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23
Q

__ __ is then deposited in osteoid tissue as it is organized into bone

A

Calcium phosphate

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24
Q

Osteoblasts are trapped in the matrix and become ___

A

Osteocytes

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25
Q

Spicules of bone soon become organized and coalesce into ____

A

Lamellae (layers)

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26
Q

Concentric lamellae develop around blood vessels, forming ____

A

Osteons (haversian systems)

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27
Q

Some osteoblasts remain at the periphery of the bone and continue to lay down lamellae, forming plates of compact bone on the surfaces

A

Ok

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28
Q

Between the surface plates, the intervening bone remains speculated, or spongy

A

This spongy environment is somewhat accentuated by the action of osteoclasts that reabsorb bone

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29
Q

In the interstices of the spongy bone, the mesenchyme differentiates into __ ___

A

Bone marrow

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30
Q

During fetal and postnatal life, continuous remodeling of bone occurs by the coordinated action of __ and ___

A

Osteoclasts and osteoblasts

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31
Q

What is endochondral ossification

A

Cartilaginous bone formation

Type of bone formation that occurs in preexisting cartilaginous models

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32
Q

In a long bone, the primary center of occification appears in the ___, which forms the shaft of a bone

A

Diaphysis

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33
Q

In the primary ossification center, the cartilage cells increase in size (hypertrophy), the matrix becomes calcified, and the cells die

A

Concurrently a thin layer of bone is deposited under the perichondrium surrounding the siaphysis; thus the perichondrium becomes the periosteum

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34
Q

The perichondrium becomes the ___

A

Periosteum

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35
Q

Invasion of the vascular connective tissue by the blood vessels surrounding the periosteum breaks up the cartilage

A

Ok

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36
Q

Some invading progenitor cells differentiates into ___ ___. This process continues toward the epiphyses (end of the bones)

A

Hematopoietic cells (blood cells of the bone marrow

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37
Q

The spicules (small needle-shaped body) of bone are remodeled by action of the osteoclasts and osteoblasts

A

Osteoclasts osteoblasts

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38
Q

Lengthening of the long occurs at diaphysis epiphyseal junction

A

The lengthening of bone depends on the epiphyseal cartilage plates, whose chondrogenesis proliferate and particulate in endochondral bone formation

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39
Q

Toward the diaphysis, the cartilage cells increase in size and the matrix becomes ___

A

Calcified

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40
Q

The spicules are isolated from each other by vascular invasion from the marrow of ___ __ ) __ ___

A

Medullary cavity of long bone

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41
Q

Bone is deposited on these spicules by osteoblasts;resorption of this bone keeps the spongy bone masses relatively constant in length and enlarges the medullary cavity

A

Ok

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42
Q

Rickets is a disease in children attributable to __ ___ _

A

Vitamin d defiency

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43
Q

Vitamin D is required for __ absorption in the intestine

A

Calcium

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44
Q

A calcium defiency(related or unrelated to vitamin D) causes disturbances in ossification of the epiphyseal cartilage plates and there is disorientation of cells at the metaphysis. What is the metaphysis

A

Flared part of diaphysis nearest the epiphysis

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45
Q

What do limbs look like with rickets

A

Shortened and deformed, with severe bowing of the limb bones

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46
Q

Rickets may also delay closure of ____ of the cranial bones in infants

A

Fontanelles

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47
Q

Ossification of limb bones begins at the end of the embryonic period (56 days after fertilization). Therefore, when are there demands on the maternal supply of calcium and phosphorus

A

8 weeks

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48
Q

At birth, the diaphyses are largely ___ but most of the epiphyses are still ____

A

Ossified

Cartilaginous

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49
Q

When do secondary ossification centers appear in the epiphyses

A

First few years after birth

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50
Q

The epiphyseal cartilage cells hypertrophy and there is invasion by vascular CT

A

Ok

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51
Q

Ossification spreads rapidly and only articular cartilage and epiphyseal cartilage plat remain ___

A

Cartilaginous

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52
Q

Upon completion of growth the cartilage plate is replaced by spongy bone; the epiphyses and diaphyses are united and no further elongation of the bone occurs

A

Ok

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53
Q

In most bones , the epiphyses have fused with the diaphysis by the age of ___

A

20

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54
Q

Growth in the diameter of a bone results from deposition of bone at the ___ and from resorption on the internal medullary surface

A

Periosteum

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55
Q

The rate of deposition and resorption is balanced to regulate the thickness of compact bone and the size of the medullary cavity.

A

The internal reorganization of bone continues throughout life

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56
Q

Joints begin to develop with the appearance of __ ___ during the 6th week and by the end of the __ week they resemble adult bones

A

Condensed mesenchyme

8th

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57
Q

During the development of fibrous joints, the ___ ___ between the developing bones differentiates into dense fibrous tissue

A

Interzonal mesenchyme

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58
Q

Give an example of a fibrous joint

A

Sutures of the cranium

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59
Q

During development of the cartilaginous joints, the interzonal mesenchyme between the developing bones differentiates into __ __ or ____

A

Hyaline cartilage

Fibrocartilage

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60
Q

During development of synovial joints, the interzonal mesenchyme between the developing bones differentiates as follows:

A

Peripherally, the interzonal mesenchyme forms the joint capsular ligament and other ligaments

Centrally, the mesenchyme disappears and the resulting space becomes the joint cavity or synovial cavity

Where the mesenchyme lines the joint capsule and articular surfaces it forms the synovial membrane which secretes synovial fluid

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61
Q

What is the axial skeleton

A

Cranium, vertebral column, ribs , sternum

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62
Q

Some densely packed cells move cranial, opposite the center of the myotome, where they form the ___ _. What do these cells express

A

IV discs

PAX1, a paired box gene

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63
Q

The remaining densely packed cells fuse with the loosely arranged cells of the immediately caudal sclerotome to form the mesenchymal ___, the primordium of a body of a vertebra

A

Centrum

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64
Q

Thus, each centrum develops from two adjacent sclerotome and becomes an intersegmental structure

A

The spinal nerves now lie in a close relationship with the IV discs, and the intersegmental arteries lie on each side of the vertebral bodies

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65
Q

In the thorax, the dorsal intersegmental arteries become the intercostal arteries

A

Ok

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66
Q

Studies indicate that the regional development of the vertebral column is regulated along the anterior posterior axis by what

A

HOX AND PAX

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67
Q

WHERE IT IS SURROUNDED BY THE DEVELOPING VERTEBRAL BODIES, THE NOTOCHORD DEGENERATES ANDN DISAPPEARS.WHAT HAPPENS BETWEEN THE VERTEBRAE

A

The notochord expands to form the gelatinous center of the IV disc-the nucleus pulposus

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68
Q

The nucleus is later surrounded by circulatory arranged fibers that form the ___ ___

A

Annulus fibrosus

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69
Q

The nucleus pulposus and anulus fibrosus together constitute the ___ __

A

IV disc

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70
Q

The mesenchymal cells that surround the neural tube form the ___ __, the primordium of the ___ ___

A

Neural arch

Vertebral arch

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71
Q

The mesenchymal cells in the body wall form the __ __, which form the ribs in the thoracic region

A

Costal processes

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72
Q

Remnants of the notochord may persist and form a ___, a rare neoplasm

A

Chordoma

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73
Q

Approximately 1/3 of these slowly growing chordoma, malignant tumors occur at the base of the cranium and extend to the ____

A

Nasopharyx

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74
Q

Chordoma infiltrate bone and are difficult to remove

A

They also develop in the lumbosacral region. Surgical resection has provided long term disease free survival for many people

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75
Q

During the _ week, chondrification centers appear in each mesenchymal vertebra

A

6th

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76
Q

At the end of the embryonic period the two centers in each __ fuse to form a cartilaginous centrum

A

Centrum

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77
Q

Concomitantly, the centers in the neural arches fuse with each other and the centrum

A

The spinous and transverse processes develop from extensions of the chondrification centers in the neural arch

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78
Q

___ spreads until a cartilaginous vertebral column is formed

A

Chondrification

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79
Q

Ossification of typical vertebrae begins during the embryonic period and usually ends by the __ years

A

25th

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80
Q

There are two primary ossification centers in the centrum, the __ and ___, which soon fuse to form one another

A

Dorsal ventral

81
Q

Three primary centers are present by the _ week: one in the centrum and one in each half of the neural arch

A

8th

82
Q

Ossification becomes evident in the neural arches during the __ week

A

8th

83
Q

Ossification becomes evident in the neural arches during the _ week

A

8

84
Q

At birth each vertebra consists of three bony parts connected by ___

A

Cartilage

85
Q

The bony halves of the vertebral arch usually fuse during the first - years

A

3-5

86
Q

The arches first unite in the lumbar region and union progresses cranially

A

The vertebral arch articulates with the centrum at cartilaginous neurocentral joints, which permit the vertebral arches to grow as the spinal cord enlarges

87
Q

The neurocentral joints disappear when

A

When the vertebral arches fuse with the centrum during the 3rd to 6th years

88
Q

What are the five ossification centers that appear in the vertebrae after puberty

A

One for the tip of the spinous process

One for the tip of each transverse process

Two anular epiphyses, one on the superior rim and one on the inferior rim of the vertebral body

89
Q

The __ __ is a composite of the anular epiphyses and the mass of bone between them

A

Vertebral body

90
Q

All secondary centers unite with the rest of the vertebrae at __ years of age

A

25

91
Q

Where are there variations in the ossification of vertebrae

A

C1, c2, c7 vertebrae , and in lumbar vertebrae , sacrum and coccyx

92
Q

Most people have _ cervical, _ thoracic, _ lumbar, and _ sacral vertebrae

A

7, 12, 5, 5

93
Q

An apparent extra (or absent) vertebra in one segment of the column may be compensated for by an absent (or extra) vertebra in an adjacent segment

A

Ok

94
Q

Klippel-feel syndrome(brevicollis) features

A

Short neck, low hairline, restricted neck movements, fusion of vertical vertebral bodies, abnormalities of brainstem and cerebellum

95
Q

In most cases , the number of cervical vertebral bodies is fewer than normal due to fusion of vertebrae before birth

A

In some cases, there is a lack of segmentation of several elements of the cervical region of the vertebral column

96
Q

The number of cervical nerve roots may be normal but they are small, as are the IV foramina.

A

Persons with this syndrome may have other birth defects, including scoliosis and urinary tract disorders

97
Q

What do ribs develop from

A

Mesenchymal costal processes of the thoracic vertebrae

98
Q

The ribs become __ during the embryonic period and ___ during the fetal period

A

Cartilaginous

Ossify

99
Q

What is the original site of union of the costal processes with the vertebrae replaced by

A

Costovertebral synovial joints

100
Q

True ribs

A

1-7 attach by their own cartilages to the sternum

101
Q

False fibs

A

8-12 attach to their sternum trough the cartilage of another rib or ribs

102
Q

Floating ribs

A

The last two pairs of ribs 11, 12 do not attach to the sternum

103
Q

In development of the sternum, A pair of vertical mesenchymal bands-__ __-develop ventrolaterally in the body wall

A

Sternal bars

104
Q

___ occurs in sternal bars as they move medially

A

Chondrification (converion into cartilage)

105
Q

Sternal bars fuse craniocaudlaly in the median plane to form cartilaginous models of the ___, ___, and ____ ___

A

Manubrium, sternebrae, and xiphoid process

106
Q

Sternum: centers of ossification appear ____ in the sternum before birth, except the ossification center of the ___ __, which appears during ___

A

Craniocaudally
Xiphoid process
Childhood

107
Q

The xiphoid may never completely ___

A

Ossify

108
Q

The cranium develops from ___ surrounding the developing brain

A

Mesenchyme

109
Q

Neurocranium

A

Bones of the cranium enclosing the brain

110
Q

Viscerocranium

A

The bones of the facial skeleton derived from the pharyngeal arches

111
Q

__ ___ of the neurocranium forms the bones of the base of the cranium

A

Endochondral ossification

112
Q

The ossification pattern of the neurocranium has a definite sequence. What is it

A

Occipital first, ten sphenoid, then ethmoid

113
Q

The __ __, or __ __ forms around the cranial end of the notochord and fuses with the cartilages derived from the sclerotome regions of the occipital somites

A

Parachordal cartilage or basal plate

114
Q

The parachordal cartilage or basal plate, contributes to the ___ of the occipital bone; later, extensions grow around the cranial end of the spinal cord and form the boundaries of the __ ___

A

Base

Foramen magnum

115
Q

What is the foramen magnum

A

Large opening int he basal part of the occipital bone

116
Q

The __ __ forms around the developing pituitary gland and fuses to form the body of the sphenoid bone

A

Hypophysial cartilage

117
Q

The __ __ fuse to form the body of the ethmoid bone

A

Trabeculae cranial

118
Q

The __ __ forms the lesser wing of the sphenoid bone

A

Ala orbitalis

119
Q

Otic capsules envelop around the otic vesicles, the primordia of the __ __, and form the __ and __ parts of the temporal bone

A

Internal earths

Petrous, mastoid

120
Q

Nasal capsules develop around the nasal sacs and contribute to the formation of the __ __

A

Ethmoid bone

121
Q

Membranous ossification occurs in the head mesenchyme at the sides and top of the brain, forming the ___

A

Calvaria

122
Q

During fetal like , the flat bones of the calvaria are separated by dense CT membranes that form fibrous joints-the ___ of the calvaria

A

Sutures

123
Q

Six large areas __, are present where several sutures meet

A

Fontanelles

124
Q

The softness of the bones and their loose connections at the sutures enable the calvaria to undergo changes of a shape during birth (___ of fetal cranium)

A

Molding

125
Q

During birth, The frontal bones become __, the occipital bone is __ __ and one parietal bone slightly overrides the other one

A

Flat

Drawn out

126
Q

After birth when does the shape of the calvaria return to normal

A

Few days

127
Q

The cartilaginous viscerocranium is derived fromt he cartilaginous skeleton of the first __ pairs of pharyngeal archess

A

2

128
Q

The dorsal end of the first pharyngeal arch cartilage forms the __ and __ of the middle ear

A

Malleus incus

129
Q

The dorsal end of the second pharyngeal arch cartilage forms a portion of the __ of the middle ear and __ process of the temporal bone.

A

Stapes

Styloid

130
Q

The ventral end of the second pharyngeal arch ossifies to form the __ __ of the ___ ___

A

Lesser bone

Hyoid bone

131
Q

The third, fourth, and sixth pharyngeal arch cartilages for only in the ___ parts of the arches.

A

Ventral

132
Q

The third arch cartilages form the __ __ of the ___ ___

A

Greater horns

Hyoid bone.

133
Q

The fourth and sixth pharyngeal arch cartilages fuse to form the ___ cartilages except for the ____

A

Laryngeal

Epiglottis

134
Q

___ ossification occurs in the maxillary prominence of the first pharyngeal arch and subsequently forms the squamous temporal, maxillary and zygomatic bones

A

Membranous

135
Q

The squamous temporal bones become part of the ____

A

Neurocranium

136
Q

The mandibular prominence forms the ___

A

Mandible

137
Q

Some __ ossification occurs int he median plane of the chin and in the mandibular condyle

A

Endochondral

138
Q

The cranium of a neonate is __ in proportion to the rest of the skeleton, and the face is __ compared with the calvaria

A

Large

Small

139
Q

Why is the face small on a newborn

A

Small size of jaws, absence of Paranasal sinuses and underdevelopment of hte facial bones

140
Q

After recovering from molding, the neonates cranium is ___ and its bones are __

A

Round

Thin

141
Q

The _ __ permit the brain and calvaria to enlarge during infancy and childhood.

A

Fibrous sutures

142
Q

When is the increase in size the greatest for the postnatal cranium and why

A

First two years . The period of most rapid growth of the brain

143
Q

The calvaria continues to expand to conform to brain growth until _ years, after which its size usually increases slightly for 3-4 years bc of thickening of its bones

A

16

144
Q

There is also rapid growth of the face and jaws, coinciding with eruption of the primary (___) teeth

A

Deciduous

145
Q

Facial changes are more marked after secondary (__) teeth erupt

A

Secondary

146
Q

There is concurrent enlargement of the frontal and facial regions , associated with the increase in the size of the ___ ___

A

Paranasal sinuses (maxillary sinuses

147
Q

what is growth of the Paranasal sinuses important for

A

Resonance to the voice

148
Q

Accessory ribs, usually rudimentary, result from the development of costal processes from the __ or __ vertebrae

A

Cervical

Lumbar

149
Q

The most common accessory rib is a ___ rib ,but it is clinically ___

A

Lumbar

Insignificant

150
Q

A cervical rib occurs in -% of people and os often fused with the _ rib

A

.5-1

1st

151
Q

A cervical rib is usually attached to the __ of the sternum or the _ cervical vertebrae

A

Manubrium

7th

152
Q

Why would a cervical rib produce neurovascular symptoms

A

Pressure of a cervical rib on the brachial plexus of nerves, partly in the neck and axilla, or on the subclavian artery often produces neurovascular symptoms (paralysis and anesthesia of the upper limb

153
Q

Usually developing vertebral bodies have _ chondrification centers that soon unite

A

2

154
Q

What is a hemivertebra

A

Failure of one of the chondrification centers to appear and subsequent failure of half of the vertebra to form

155
Q

Hemivertebra is the most common cause of __ __ or the vertebral column

A

Congenital scoliosis

156
Q

Rachischisis

A

Vertebral abnormalities in a complex group of anomalies (spinal dysgraphia) that primarily affect axial structures

157
Q

In neonates with rachischisis, the neural folds do not fuse, either because of faulty induction by the underlying notochord or bc of a teratogenic agent

A

Ok

158
Q

Acrania

A

The neurocranium is absent and there are major birth defects of the vertebral column that are incompatible with life

159
Q

Acrania is associated with ____ and ____

A

Meroencephaly

Rachischisis

160
Q

What is meroencephaly

A

Partial absence of the brain

161
Q

What is rachischisis

A

Extensive clefts in the vertebral arches of the vertebral column

162
Q

When does meroencephaly occur

A

Cranial end of the neural tube does not close during the 4th week of development, resulting in subsequent failure of the calvaria

163
Q

Craniosynostosis

A

Several birth defects result from prenatal fusion of the cranial sutures

164
Q

Cause of craniosyntosis

A

Unclear but genetic factors appear to be important. HOX(MSX2 and ALX4) mutations have been implicated in cases

165
Q

Craniosyntosis is more common in ___ and often associated with what

A

Males

Other skeletal defects

166
Q

The type of cranial deformation produced in craniosyntosis depends on what

A

Which sutures close prematurely

167
Q

Scaphocephaly

A

Sagittal suture closes first

Cranium elongated and wedge shaped

168
Q

Most common craniosynostosis

A

Scaphocephaly

169
Q

Brachycephaly

A

Premature closure of the coronal suture

High , tower like cranium

170
Q

Plagiocephaly

A

Coronal suture closes prematurely on one side only

Cranium twisted and asymmetrical

171
Q

Trigonocephaly

A

Premature closure of the frontal (metopic) suture results in a defect of the frontal bone and other defects

172
Q

What is the appendicular skeleton

A

Pectoral and pelvic girdles and limb bones

173
Q

During the _ week the mesenchymal bone models in the limb undergo chondrification to form ___ cartilage bone models

A

Hyaline

174
Q

The clavicle initially develops by __ ___ and it later forms growth cartilages at both ends

A

Intramembranous ossification

175
Q

The models of the pectoral girdle and uppper limb bones appear slightly before those of the pelvic girdle and lower limb bones

A

The bone models appear in a proximodistal sequence

176
Q

The moleculcular mechanism of limb morphogenetic is regulated by specialized signaling centers along three axes of development . Patterning in the developing limbs is controlled by ___ and other complex signaling pathways

A

HOX

177
Q

Ossification begins in the long bones by the __ week

A

8th

178
Q

By _ weeks, primary ossification centers have appeared in nearly all limb bones

A

12

179
Q

The ___ begin to ossify before any other bones in the body, followed by __

A

Clavicle

Femurs

180
Q

Virtually all primary centers of ossification are present at birth

A

Diaphyseal

181
Q

The centers for the distal end of the femur and the proximal end of the tibia usually appear when

A

Last month of intrauterine life (34-38 weeks)

182
Q

The centers of the other bones appear after birth

A

Ok

183
Q

The part of the bone ossified from the secondary center is the _—

A

Epiphysis

184
Q

The bone formed fromt he primary center in the diaphysis does not fuse at the epiphyseal cartilage plate with that formed fromt he secondary centers in the epiphysis until the bone grows to its adult length

A

This delay enables lengthening of the bone to continue until the final size is reached

185
Q

A radiologist can determine bone age by assessing the ossification centers using two criteria

A

The time of appearance of calcified material in the diaphysis, epiphysis or both is specific for each diaphysis and epiphysis and for each bone and sex
The disappearance of the dark line representing the epiphyseal cartilage plate indicates that te epiphysis has fused with the diaphysis

186
Q

Fusion of the diaphyseal-epiphyseal centers , which occurs at specific times for each ap I physics, happens 1-2 years earlier in __ than ___

A

Females

Males

187
Q

__ is the most common cause of dwarfism

A

Achondroplasia

1/15000

188
Q

In achondroplasia, the limbs become bowed and short. Why

A

A disturbance of endochondral ossification at the epiphyseal cartilage plates, particularly of the long bones, during fetal life

189
Q

What do babies with achondroplasia look like

A

Trunk is short and head is enlarged with a bulging forehead and a scooped out nose (flat nasal bone)

190
Q

Inheritance pattern of achondroplasia

A

AD, 80% can arise from new mutations-rate increases with paternal age

191
Q

The majority of achondroplasia is due to a point mutation in ____

A

F.1,11,12 in the FGFR3 gene

192
Q

What does f.1,11,12 in the FGFR3 gene do with a point mutation

A

Magnification of the normal inhibiting effect of endochondral ossification, specifically int he zone of chondrocyte proliferation
-shortened bones,but does not affect growth of bone width(periosteal growth)

193
Q

Congenital infantile hyperpituitarism

A

Causes abnormally rapid growth in infancy

Rare

194
Q

What does congenital infantile hyperpituitarism result in

A

Gigantism

195
Q

In adults, hyperpituitarism results in ___

A

Acromegaly

196
Q

In acromegaly, the epiphyseal and siaphyseal centers of the long bones fuse, thereby preventing ___ of the bones

A

Elongation

197
Q

Both gigantism and acroemegaly result from an excessive secretion of __ __

A

Growth hormone

198
Q

Acromegaly is in _ and gigantism i sin _

A

Adults

Kids

Embryology (12 decks)

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