Lab 6 Human development 1 Flashcards
cell theory
cells come from preexisting cells
first trimester
embryo develops cell layers that are precursors to organ systems
second trimester
characterized by growth in length, mass gain, and appearance of function organ systems
third trimester
increases in length and mass continue
all organ systems are either functional or ready to be functional upon birth
morphogenesis
general term for all processes involved in the specialization of cells in the developing conceptus and the migration of those cells to produce anatomical structures and function
mitosis
results in daughter cells that have a chromosome compliment identical to the parent cells
diploid results
meiosis
sequence of two divisions of a diploid germinal cell to produce haploid cells
fertilization
the process of the sperm and ovum joining their haploid nuclei to produce a diploid zygote
ovulation
the process that the ovary releases an egg
cleavage
repeated mitotic divisions of the zygote
implantation
day six when blastocyst touches the endometrium
endoderm forms
gastrointestinal and respiratory tracts
glands of digestive system
ectoderm forms
neural tube retina optic nerves epidermis of skin nerves teeth innter ear
mesoderm forms
heart and great vessels pericardium connective tissue kidneys, spleen urogenital system
Parturition
birth
uterine muscle contractions to expel the fetus
