1. Which role does the placenta have in embryo growth and development?
A. Digestion of nutrients
B. Perception of stimuli
C. Transmission of electrical signals
D. Providing of nutrients and oxygen Correct
Explanation
The placenta provides nutrients and oxygen to the developing embryo, facilitating growth via the umbilical cord. It does not digest nutrients, perceive stimuli, or transmit electrical signals, which are unrelated to its primary function.
2. Which term is used for the outer cells of the human blastocyst?
A. Embryonic disk
B. Neural plate
C. Trophoblast Correct
D. Mesenchyme
Explanation
The trophoblast forms the outer layer of the blastocyst, contributing to the placenta and supporting implantation. The embryonic disk, neural plate, and mesenchyme are involved in other developmental processes, not the outer cells.
3. Which time period is regarded as the germinal period of prenatal development?
A. The first two weeks of postconception Correct
B. The third to the eighth week of postconception
C. The ninth to sixteenth week of postconception
D. The ninth week until birth
Explanation
The germinal period spans the first two weeks postconception, from fertilization to implantation. Later periods (embryonic and fetal) cover subsequent weeks, making other options incorrect.
4. How do teratogens affect prenatal development?
A. They can cause depression in newborns
B. They can cause anoxia in newborns
C. They can cause malformed facial features in newborns Correct
D. They can cause autism in newborns
Explanation
Teratogens, such as drugs or infections, can cause physical malformations like facial deformities in newborns by disrupting prenatal development. Depression and autism are not directly linked, and anoxia is a secondary effect, not a primary outcome.
5. A seven-month-old baby begins vocalizing consonant-vowel sequences such as 'ma-ma-ma' and 'da-da-da.' Which form of intentional vocalization does this illustrate?
A. Gesturing
B. Cooing
C. Babbling Correct
D. Holophrasis
Explanation
Babbling involves repetitive consonant-vowel sequences like 'ma-ma-ma,' typical in infants around seven months. Cooing is earlier vowel sounds, holophrasis involves single words, and gesturing is non-vocal.