Reproductive system Flashcards
Explain Fertilization.
Fertilization – when a sperm fuses with an egg to form a zygote
What is Conceptus?
Conceptus – the developing offspring
Explain Preembryo.
Preembryo – conceptus from fertilization until it is two weeks old
Explain Embryo.
Embryo – conceptus during the third through the eighth week
Definition Fetus.
Fetus – conceptus from the ninth week through birth
Relative Size of Human Conceptus
Relative Size of Human Conceptus
See picture.
Explain the process from Zygote to Blastocyst.
Cleavage: From Zygote to Blastocyst
See picture.
Explain Implantation of the Blastocyst
Implantation of the Blastocyst
Explain Placentation.
Placentation
Explain Gastrulation.
Gastrulation
- During the 3rd week, the two-layered embryonic disc becomes a three-layered embryo
- The primary germ layers are ectoderm, mesoderm, and endoderm
- Primitive streak – raised dorsal groove that establishes the longitudinal axis of the embryo
Explain Folding of the Embryonic Body.
Folding of the Embryonic Body
Explain Primary Germ Layers.
Primary Germ Layers
- Serve as primitive tissues from which all body organs will derive
- Ectoderm – forms structures of the nervous system and skin epidermis
- Endoderm – forms epithelial linings of the digestive, respiratory, and urogenital systems
- Mesoderm – forms all other tissues
- Endoderm and ectoderm are securely joined and are considered epithelia
Explain Organogenesis.
Organogenesis
- Gastrulation sets the stage for organogenesis, the formation of body organs
- By the 8th week all organ systems are recognizable
Explain the Embryonic Development of CNS.
Embryonic Development of CNS
Explain Neural Tube and Primary Brain Vesicles.
Neural Tube and Primary Brain Vesicles
Explain Secondary Brain Vesicles.
Secondary Brain Vesicles
Explain Space Restriction and Brain Development.
Space Restriction and Brain Development
Explain Endodermal Differentiation.
Endodermal Differentiation
Explain Specialization of the Mesoderm.
Specialization of the Mesoderm.
Explain Derivatives of Primary Germ Layers.
Derivatives of Primary Germ Layers
Desbrice Developmental Events of the Fetal Period (8-12 weeks).
Developmental Events of the Fetal Period (8-12 weeks)
Desbrice Developmental Events of the Fetal Period (13-20 weeks).
Developmental Events of the Fetal Period (13-20 weeks).
Desbrice Developmental Events of the Fetal Period (21-40 weeks).
Developmental Events of the Fetal Period (21-40 weeks).
Explain Development of Fetal Circulation.
Development of Fetal Circulation.
- Unique vascular modifications seen in prenatal development include umbilical arteries and veins, and three vascular shunts (occluded at birth)
- Ductus venosus – venous shunt that bypasses the liver
- Foramen ovale – opening in the interatrial septa to bypass pulmonary circulation
- Ductus arteriosus – transfers blood from the right ventricle to the aorta
