480.Hirschsprung's disease indicates a developmental abnormality in which of the following embryonic tissues?

 A. Ectoderm
B. Endoderm
C. Neural crest
D. Neural ectoderm

Ans-c.Neural crest

The baby has Hirschsprung's disease, which is due to an absence of
ganglion cells in the wall of the colon. Neural crest cells contribute to the formation of many adult
structures. Among these are all of the postganglionic neurons of the autonomic nervous system and
the sensory neurons of the peripheral nervous system.

479.At which of the following ages does fetal movement first occur?

A. 1 month
B. 2 months
C. 4 months
D. 6 months

Ans-B.2months
Neuromuscular development is sufficient to allow fetal movement in the
eighth week of life. Other features of Week 8 include the first appearance of a thin skin, a head as
large as the rest of the body, forward-looking eyes, appearance of digits on the hands and feet,
appearance of testes and ovaries (but not distinguishable external genitalia), and a crown-rump length
of approximately 30 mm. By the end of the eighth week, nearly all adult structures have at least begun
to develop, and the fetus "looks like a baby.

478 :Bleeding joints is a characteristic feature of:

  1. Vitamin C deficiency.
  2. Hemophilia.  
  3. Vitamin K deficiency. 
  4. Thrombocytopenia.

Ans-2.Hemophilia