ANAT20006 Lecture Notes - Lecture 5: Mesonephric Duct, Yolk Sac, Pancreatic Bud
12 Jun 2018
School
Department
Course
Professor
LECTURE 5
EMBRYOLOGY (4) & HUMAN FORM & FUNCTION
EMBRYOLOGY (4)
L
•(2) fuse to form the intra-embryonic
cavity; the coelom. With lateral folding,
mesoderm is recruited to gut wall.
REGIONAL PATTERNING OF THE GUT
TUBE
•(3) gut tube develops into oesophagus etc. From
the foregut there are a bunch of organs
branching out. A main question is what happens
to the yolk sac?
•(4) the yolk sac is still connected via the yolk
stalk, which becomes part of the umbilical cord.
The yolk sac provides nutrients until the placenta is
formed and can take over around week 7.
•(5) the yolk sac is still visible.
Lecture 5 - Wednesday 2 August 2017
ANAT20006 - HUMAN STRUCTURE & FUNCTION
PANCREAS
•(6) Rotation brings
ventral and dorsal
pancreas together. On
the left hand side
where the liver buds
out we have a ventral
bud forming and on
the opposite side we
have dorsal. The
ventral part will
eventually turn around
to form the dorsal
pancreatic bud and
they will fuse to form
the pancreas.
GENITAL TRACTS
•(7) intermediate
mesoderm forms
nephric (wolffian) duct. On
the female only the mullerian
duct remains to form uterus
and upper part of the vagina.
In males, the wolffian duct
has no connection to the
coelom.
• Coelomic epithelium →
peritoneum
•Müllerian duct → oviduct,
uterus
HUMAN FORM &
FUNCTION
•(10) classification of
organisms - taxonomy.
→ Aristotle (384-322 BC)
•Known for both philosophical work and also his dissection of embryos. He tried to categorise
living animals based on the labels 1. Plant or animal and 2. Living space (land, air or water).
→ Carl Linnaeus (1707-1778)
•Categorised based on physical and structural similarities. We still use his basic system.
•(11) begins with kingdom, phylum, class,
order, family, genus, species, sub species.
•Kids prefer candy over fresh green
spinach.
•(12) human example. With each level we
lose some other animals because they
don’t have the features anymore.
Lecture 5 - Wednesday 2 August 2017
ANAT20006 - HUMAN STRUCTURE & FUNCTION
•(15)
KINGDOM: ANIMALIA
•(16) need these 3 features to belong to kingdom animalia:
•1. Capable of independent movement
•2. External energy source
•3. Cells surrounded by cell membrane (and not rigid cell wall)
SUPERPHYLUM: COELOMATE
•(17) superphylum coelomate: some of these features you can only see during development and
not necessarily in
the adult.
•3 main features:
•1. Three germ
layers: ectoderm.
mesoderm,
endoderm
•2. Fluid filled
internal body
cavity = coelom
•3. Gut tube
suspended in
coelom
Lecture 5 - Wednesday 2 August 2017
ANAT20006 - HUMAN STRUCTURE & FUNCTION
Document Summary
L: (2) fuse to form the intra-embryonic cavity; the coelom. With lateral folding, mesoderm is recruited to gut wall. Tube: (3) gut tube develops into oesophagus etc. From the foregut there are a bunch of organs branching out. A main question is what happens to the yolk sac: (4) the yolk sac is still connected via the yolk stalk, which becomes part of the umbilical cord. The yolk sac provides nutrients until the placenta is formed and can take over around week 7: (5) the yolk sac is still visible. Pancreas: (6) rotation brings ventral and dorsal pancreas together. On the left hand side where the liver buds out we have a ventral bud forming and on the opposite side we have dorsal. The ventral part will eventually turn around to form the dorsal pancreatic bud and they will fuse to form the pancreas. Genital tracts: (7) intermediate mesoderm forms nephric (wolffian) duct.
