Embryogenesis Flashcards
Features of sperm cell
Head- acrosome, genetic material(DNA)- nuclear envelope
Middle- mitochondria(energy to help propel the sperm)
Tail- flagellum (propels sperm towards egg cell)
Features of the egg cell
Zona pellucida (glycoproteins- sperm binding)
Mitochondria- energy
Genetic material- DNA- nuclear envelope
Plasma membrane
Function of acrosome
Chews up the glycoprotein to prevent polyspermy (other sperm cells from binding to the egg cell)
Zygote
Egg cell + sperm
Early cleavage
2 cells- 4 cells
Cleavage
Division of cells without growth (2 cells- 32 cells)
Name the steps in embryogenesis
Zygote(from fertilization)- cleavage- cell differentiation- blastulation- gastrulation- neurulation
At what stage in embryogenesis does the zona pellucida disappear
Blastulation
what is morula
formed during cleavage at 32 cells
“mulberry”
what are the differentiated cells at the beginning of blastulation
trophoblasts & embryoblasts
what do embryoblasts end up as
embryo
end function of trophoblast
aids in embryo implantation to the uterus (placenta)
what 2 cells start the gastrulation process
epiblasts and hypoblasts
Name the 3 germ layers and the cells they are formed from
Ectoderm- epiblasts
mesoderm- primitive streak
endoderm- hypoblasts
what structure depicts the beginning of neurulation
Notochord
which category of mesoderm forms the notochord
axial mesoderm
location and function of the cortical granules
underneath the plasma membrane; chews up the zona pellucida
what forms the neural tube
the neural plate formed by the notochord leaks into the mesoderm to form the neural tube
location & function of neural crest cells
Ectoderm; brain & spinal cord
Function of neural tube
PNS & SNS; other bones and connective tissue of face
Name the categories of the mesoderm
- Axial mesoderm- notochord
- paraxial mesoderm- somites- differentiates into muscles, cartilage, bone & dermis
- lateral mesoderm- heart, blood vessels, body wall, organ muscle
- intermediate mesoderm- kidney, adrenal glands, genitourinary
differentiated cells/organs of ectoderm
skin(epidermis); skin appendages- hair, nails; nervous system, brain
Differentiated cells/organs of mesoderm
muscles, genitourinary, skeletal, notochord, circulatory system, connective tissue, bone
Differentiated cells/organs of endoderm
the epithelial lining of the digestive tract- stomach, liver, colon, pancreas; pulmonary- lungs, distal ends of thr urinary tract
