development II

Question 1

cytoplasmic specification

Answer 1

intrinsic information is inherited from the mother cell through cell division.

Question 2

during cytoplasmic specification unequally distributed components of the cytoplasm influence ____ of the cell to a ____ cell type

Answer 2

-commitment
-particular

Question 3

induction

Answer 3

extrinsic information is received from the cell’s surroundings

Question 4

each step in developmental hierarchy is a necessary ____ event for the next

Answer 4

-preliminary

Question 5

both forms of cell specification determine which ___ get expressed and allows for ____ cell function

Answer 5

-genes
-specialized

Question 6

amniotes

Answer 6

reptiles and mammals for monophyletic group within vertebrates; develop in the amniotic sac

Question 7

functions of the amniotic sac

Answer 7

-provides an aqueous environment for floating
-serves as protection from mechanical shock adhesions

Question 8

amniotic egg contains ___ extraembryonic membranes which are…

Answer 8

four
-amnion
-yolk sac
-allantois
-chorion

Question 9

amniotic egg: what stores yolk to sustain the embryo

Answer 9

yolk sac

Question 10

amniotic egg: storage of metabolic wastes during development, respiratory surface for exchange of oxygen and carbon dioxide

Answer 10

allantois

Question 11

amniotic egg: lies beneath eggshell, encloses embryo and other membranes

Answer 11

chorion

Question 12

later during amniotic egg development, allantois and chorion fuse to form respiratory surface for more oxygen

Answer 12

chorioallantoic membrane

Question 13

significance of amniotic egg:

Answer 13

-life support system
-made internal fertilization a requirement
-life on land could exist and not dry out

Question 14

placental mammals

Answer 14

embryo is protected and nourished by the placenta; nourishment from mother

Question 15

placental mammals: amnion

Answer 15

remains unchanged same function

Question 16

placental mammals: yolk sac

Answer 16

contains no yolk but is not fluid-filled
-source of stem cells that give rise to blood, lymphoid cells, and gametes

Question 17

placental mammals: allantois

Answer 17

not needed to store wastes
-contributes to the formation of the umbilical cord

Question 18

placental mammals: chorion

Answer 18

forms most of the placenta along with the adjacent uterine endometrium
-secretes materials that block normal maternal immune response

Question 19

what tissues derive from the ectoderm?

Answer 19

-nervous system
-epidermis
-hair

Question 20

gastrocoel forms primitive gut
-digestive tract lining
-lining of the pharynx and lungs
-most of the liver and pancreas
-thyroid, parathryoid glands, thymus

Answer 20

endoderm

Question 21

mesoderm

Answer 21

somites
-most muscles, back, body wall, and limbs
-axial skeleton
-dermis of dorsal skin
-heart