Term
|
Definition
| Study of development of a unicellular zygote into a complete organism |
|
|
Term
|
Definition
| An egg can be fertilized within 12-24 hours after ovulation. Fertilization occurs in the oviduct when sperm traveling from the vagina encounters an egg |
|
|
Term
|
Definition
A series of rapid mitotic divisions during early embryonic development.
Cleavage results in smaller cells with an increased surface area allowing gas and nutrient exchange. |
|
|
Term
| WHAT HAPPENS DURING CLEAVAGE? |
|
Definition
1)A solid ball of embryonic cells, known as the morula, is formed.
2) Blastulation Occurs: The morula develops a fluid-filled cavity called the blastocoel, which by the fourth day becomes a hollow sphere of cells called the blastula.
3) The blastula is the stage of the embryon that implants into the uterus |
|
|
Term
|
Definition
| Once the blastula is implanted into the uterus, the blastula transforms into a 3-layer structure called a gastrula |
|
|
Term
|
Definition
| 3 primary germ layers responsible for the development of tissues, organs, and organ systems |
|
|
Term
| GERM LAYERS OF THE GASTRULA |
|
Definition
1) Ectoderm- Integument System, Eye Lens, Eye Retina, & Nervous System
2) Endoderm- Epithelial linings of the digestive & respiratory tract, Liver, Pancreas, Thyroid, & Bladder Lining
3)Mesoderm- Musculoskeletal System, Circulatory System, Excretory System, Gonads, & Connective Tissue |
|
|
Term
|
Definition
| When germ layers begin to develop into a rudimentary nervous system |
|
|
Term
| WHAT HAPPPENS DURING NEURULATION? |
|
Definition
1) A rod of mesodermal cells called the notochord develops along the longitudinal axis
2)Neural folds grow up and fuse into a neural tube which gives rise to the brain and spinal cord
3) The tips of the neural tube form neural crest cells that grow and give rise to sensory ganglia, adrenal medulla, schwann cells, etc. |
|
|
Term
|
Definition
1) Organogenesis- the body organs begin to form
2)Growth- the organs increase in size
3)Gametogenesis- Eggs develop in women and sperm develop in men |
|
|
Term
|
Definition
Many animals develop outside of the mother's body in the form of eggs. Eggs have these embryonic membranes:
1) Chorion- lines the inside of the shell and permits gas exchange
2)Allantois- sac-like structure involved in respiration and excretion and contain blood vessels to transport materials
3)Amnion- encloses amniotic fluid that protects the embryo from shock
4)Yolk sac- encloses the yolk and transfer food to the developing embryo |
|
|
Term
|
Definition
| Human Pregnancy, lasts 9 months and can be divided into 3 trimesters |
|
|
Term
|
Definition
| Major organs begin to develop. Eyes, gonads, liver, and limbs start to form. Bone begins to form. Brain is fairly developed.Embryo is referred to as a fetus at 8 weeks. |
|
|
Term
|
Definition
| Fetus Grows. Face appears human. Fingers & toes elongate. |
|
|
Term
|
Definition
| During the 9th month, antibodies are transferred to protect the fetus and the fetus has less room to move about |
|
|
Term
|
Definition
Childbirth is accomplished by labor, a series of strong uterine contractions.
The embryo develops into an adult through maturation. |
|
|
