Dental Assisting Online for Modern Dental Assisting Test Bank 14th Edition | Smith & Robinson

TEST BANK
Dental Assisting Online for Modern Dental Assisting
JEFFREY R. SMITH, DEBBIE S. ROBINSON
14th Edition

,Chapter 1. Oral Embryology and Histology



1. Which of the following is the process by which the cells of the fertilized egg divide and
form a ball of cells during embryonic development?
A. Cleavage
B. Differentiation
C. Organogenesis
D. Implantation
Answer: A. Cleavage
Rationale: Cleavage is the series of rapid mitotic divisions that occur after fertilization,
leading to the formation of a ball of cells known as the morula.
DIF: Easy
TOP: Embryonic development
MSC: Multiple Choice
2. During the first week of embryonic development, the fertilized egg becomes a structure
called a:
A. Zygote
B. Blastocyst
C. Morula
D. Embryo
Answer: B. Blastocyst
Rationale: After fertilization and cleavage, the ball of cells (morula) forms into a
blastocyst, which implants into the uterine wall.
DIF: Easy
TOP: Embryonic development
MSC: Multiple Choice
3. The oral cavity begins to develop during which of the following stages of embryonic
development?
A. Zygote
B. Fetal
C. Pre-implantation
D. Embryonic
Answer: D. Embryonic
Rationale: The development of the oral cavity starts during the embryonic stage, around
the third week of pregnancy, as the facial structures begin to form.
DIF: Moderate
TOP: Oral cavity development
MSC: Multiple Choice
4. The process by which the neural tube forms and begins to develop into the brain and
spinal cord is known as:
A. Gastrulation
B. Neurulation
C. Cleavage
D. Organogenesis

, Answer: B. Neurulation
Rationale: Neurulation is the process where the neural tube forms, which later gives rise
to the central nervous system (brain and spinal cord).
DIF: Moderate
TOP: Neural development
MSC: Multiple Choice
5. Which of the following is the primary function of the mesoderm layer in embryonic
development?
A. Formation of the nervous system
B. Development of the skin and hair
C. Formation of muscles, bones, and circulatory systems
D. Formation of the digestive system
Answer: C. Formation of muscles, bones, and circulatory systems
Rationale: The mesoderm layer gives rise to structures such as muscles, bones, and the
circulatory system during embryonic development.
DIF: Moderate
TOP: Germ layers
MSC: Multiple Choice
6. The term "histology" refers to the study of:
A. The structure and function of tissues
B. The development of organs
C. The structure of cells
D. The development of embryos
Answer: A. The structure and function of tissues
Rationale: Histology is the study of tissues, including their structure and function, and
their role in the body.
DIF: Easy
TOP: Histology
MSC: Multiple Choice
7. The enamel of the tooth is derived from which embryonic tissue?
A. Ectoderm
B. Mesoderm
C. Endoderm
D. Neural crest
Answer: A. Ectoderm
Rationale: Enamel, the hard outer surface of the tooth, develops from the ectodermal
layer of the embryo.
DIF: Moderate
TOP: Tooth development
MSC: Multiple Choice
8. The development of the face and oral cavity during embryonic development involves
fusion of which structures?
A. Palatal shelves
B. Maxillary and mandibular processes
C. Frontal nasal process
D. Both B and C

, Answer: D. Both B and C
Rationale: The development of the face and oral cavity involves the fusion of the
maxillary and mandibular processes, as well as the frontal nasal process.
DIF: Moderate
TOP: Facial development
MSC: Multiple Choice
9. Which structure is responsible for the formation of the teeth during embryonic
development?
A. Neural crest
B. Ectoderm
C. Mesoderm
D. Endoderm
Answer: A. Neural crest
Rationale: The neural crest cells play a crucial role in the formation of the teeth during
embryonic development.
DIF: Moderate
TOP: Tooth formation
MSC: Multiple Choice
10. The first indication of tooth development occurs during which week of embryonic
development?
A. 2nd week
B. 5th week
C. 6th week
D. 7th week
Answer: C. 6th week
Rationale: The first indication of tooth development appears during the 6th week of
embryonic development, when the dental lamina forms.
DIF: Moderate
TOP: Tooth development
MSC: Multiple Choice
11. The process of ossification refers to:
A. The formation of blood cells
B. The formation of bone
C. The development of the skin
D. The development of the digestive system
Answer: B. The formation of bone
Rationale: Ossification is the process by which bone tissue is formed from cartilage or
other connective tissue.
DIF: Moderate
TOP: Bone development
MSC: Multiple Choice
12. Which of the following is a key feature of the histological structure of enamel?
A. It is composed of collagen fibers
B. It is avascular and has no living cells
C. It contains many blood vessels
D. It has a high content of water