M9 - Human Development

Question 1

Embryonic period

Answer 1

Fertilization-8, organogenesis and body region development

Question 2

Week 1

Answer 2

Fertilization, repeated cell division and rapid incr of cells, embryo enters uterus on day 3-4

Question 3

Week 2

Answer 3

Little embryo growth, beginning of placenta development, provide nutrients to growing embryo

Question 4

Week 3

Answer 4

3 layered disc form, every structure will form from these structures, nervous sys begins to form, organ formation begins, cranial-caudal axis establishes, primitive heart tube begins

Question 5

Week 4

Answer 5

Morphogenesis, cephalocaudal folding - head and tail folding, transverse folding - creates future torso, all organ systems exist in earliest form

Question 6

Limb formation

Answer 6

Begins end of week 4, limb buds growing out of body wall, muscles contract by week 7, hands and feet form by week 7, fingers and toes appear in weeks 7-8

Question 7

Teratogens

Answer 7

Environmental agents that can disrupt development and cause congenital abnormalities, weeks 3-8 especially vulnerable

Question 8

Fetal period

Answer 8

Week 9 - birth, significant period of growth

Question 9

Preterm birth

Answer 9

Infants born before 37 weeks, 2 most serious problems: lung abnormalities, brain abnormalities, incr risk of disease later in life

Question 10

Salter-harris fracture

Answer 10

Fracture that disrupts growth plate
Can close early = shorter limb
Bone cells go into overdrive = longer bone