Human Development

Question 1

Describe the sperm cell:

Answer 1

tail, body (lots of mitochondria), and head with genetic material and acrosome.

Question 2

Describe fertilization:

Answer 2

Sperm cells rapidly approaches egg cell (secondary oocyte). The acrosome enzymes clear the zona pallucida allowing the sperm to bind. Egg cell prevents other sperm cells from attaching. DNA material is transferred. Formation of a zygote.

Question 3

Describe cleavage:

Answer 3

The single zygote undergoes many mitotic division until a morula is formed.

Question 4

Describe blastulation:

Answer 4

Morula continues to divide until a blastula forms. Blastula contains outer trophoblast, inner cell mass, and blastocele. The blastula implants itself in the uterus .

Question 5

Describe implantation:

Answer 5

blastula implants itself in the uterus. inner cell is most near the uterus to receive nutrients from maternal blood.

Question 6

Describe gastrulation:

Answer 6

formation of the three different germ layers, after implantation.

Question 7

Ectoderm:

Answer 7

outer layer.

integumentary system, nervous system.

Question 8

endoderm:

Answer 8

alimentary canal

Question 9

mesoderm

Answer 9

cardiovascular, muscles, reproductive, excretory.

Question 10

neuronation

Answer 10

mesoderm forms the notocord, which initiates change in ectoderm and the formation of neural plate. The invagination into the ectoderms allows for the formation of the neural tube which forms the cns.

Question 11

Describe the different neonatal reflexes:

Answer 11

rooting reflex: baby turns when you brush their cheek.
babinski reflex: curl toes on feet.
palmar grasp: grasp objects in hands

Question 12

Brain changes during adolescence:

Answer 12

increase prefrontal cortex.

increase limbic system (amygdala and hypothalamus)