Lecture 4 - Embryogenesis Flashcards
Embryonic Germ Layers
- Endoderm
- Mesoderm
- Ectoderm
embryonic origins from the ectoderm
Reproductive Tract
- external vagina or penile sheath
- clitoris or penis
Nervous System
- hypothalamus
- pituitary
Oral cavity
Nasal cavity
embryonic origins from the mesoderm
Repro System
- gonads
- uterus, cervix, internal vagina
- epididymus, ductus, deferens, accessory sex glands
Urinary System
Skeletal System
Blood Vessles
Muscle
embryonic origins from the endoderm
Digestive System
Respiratory System
Glandular Systems
embryonic development of the reproductive system
- development of hypothalamic-hypophyseal systems
- primordial germ cells migrate from yolk sac
- sex cord development in the gonad and mesonephric renal system regression/transformation
- sexual differentiation
- development of female tract and ovaries
- formation of broad ligament
Gestation period of cattle
280-290 days
gestation period of sheep
145-150 days
gestation period of swine
114 days
gestation period of dog
60-65 days
gestation period of cat
63-67 days
Why are the anterior and posterior pituitary so different?
- posterior originates from infundibulum coming from the 3rd ventricle (neural tissue)
- anterior originates from Ratheke’s pouch which was apart of the embryonic mouth (glandular)
Why do germ cells migrate into the gonadal ride of the embryo?
to form any tissue type
What does the repro system develop in close proximity to?
renal system
Three embryonic renal systems
- pronephroes
- mesonephros
- metanephros
Pronephros
most primitive form of kidney found in developing embryo- limited fxn and eventually degenerates