Chapter 18 Flashcards
What are the 3 stages of kidney development?
1) pronephros / pronephric duct
2) mesonephros / mesonephric kidney
3) metanephros
_______ is the earliest form of the kidney and is non-functional in mammals and degenerates
pronephros
_______ consists of 30 tubules (most apoptose) and is briefly functional in some mammals
mesonephros
The mesonephros is a source of _______ for blood development
hematopoietic stem cells
Some mesonephric tubules persist in males and become the _______ and _______ for transporting sperm from the testes to the urethra
epidymus and vas deferens
________ mesenchyme becomes committed and indues the formation of a branch of each of the paired nephric buds
metanephrogenic
The paired nephric buds formed from induction of metanephrogenic mesenchyme on nephric buds is called _______ bud, which will become the collecting ducts of the future kidney
ureteric
Ureteric buds induce the metanephrogenic mesenchyme to condense around them nd differentiate into the _______ of the final kidney
nephrons
Kidney formation involves a complex series of _______ inductions ultimately leading to the formation of the mature kidney, ureters, bladder, and helping specify the reproductive tracts of both males and females
reciprocal
the lateral plate mesoderm splits into 2 layers:
1) _______ mesoderm, which is closest to the ectoderm
2) _______ mesoderm, which is closest to the endoderm
1) somatic (parietal)
2) splanchnic (visceral)
Coelem: space between the somatic and splanchnic layers will become the _______
body cavity
the ______ is the first functional organ in vertebrates and the ______ is the first functional unit
heart
circulatory system
_______ mesoderm cells become specified very early as they migrate through the primitive streak
1) the first heart field generates only the _______ of the adult heart
2) the second heart field forms the _______ and _______ track and _______ and _______ region
cardiac
1) left ventricle
2) atria and outflow; right ventricle; inflow
- outflow: conus and truncus arteriosis
- inflow: pulmonary vein and vena cava
a descendant of the heart fields, _______ will form muscle layers
cardiomycetes
a descendant of the heart fields, _______ will for inner linings
endocardium
a descendant of the heart fields, _______ will form valves
endocardial cushions
a descendant of the heart fields, _______ will form coronary blood vessels feeding the heart
epicardium
a descendant of the heart fields, _______ will form Myocardial nerve fibers that coordinate heart beats and conduct signals
Purkinje fibers
Inductive signals that locate heart field:
1) Wnt blocked by _______ prevents the heart from forming too far anteriorly
2) BMP induces _______ production, which is critical for expression of cardia proteins
3) BMP’s blocked by _______ produced from notochord that prevents the heart from forming in the center of the embryo
1) Dickkopf (DKK)
2) Fgf8
3) Noggin
_______ mesoderm cells move toward the lateral walls of the gut, keeping contact with the endoderm, forming the 2 cardiac fields
cardiogenic
The 2 cardiac fields are brought together by inward folding of _______
splanchnopleure
Failure of the 2 endocardial tubes to merge results in _______, a condition where 2 separate and smaller heart form on each side of the body
cardia bifida
Heart cell differentiation:
_______ is produced by the posterior mesoderm cells and specifies the posterior cardiac precursor cells to become _______ portions of the heart
Retinoic acid (RA)
inflow (venous/atrial)
Cardiac field contains multipotent progenitor cells:
1) _______ form blood vessels and blood cells
2) _______ form all cells of the heart
1) hemangioblasts
2) Multipotent Cardiac Progenitor cells
Differentiation of splanchnic mesoderm driven by a series of TF’s:
1) Blood cells and blood vessels: _______
2) heart forming pathway: _______
1) Flk1
- Vegf receptor
2) Mesp1 and Nkx2.5
- activates cardiac TF’s
After the two opposing cardiogenic mesodermal populations merge a subset decreases their expression of _______, causing _______ process to form the Endocardium
N-cadherins
delamination
The lower ends of the endocardium do not fuse and produce the _______ veins that carry nutrients into the heart from the yolk sac
vitelline
When does the largely unchambered heart begins to beat?
1) in chickens
2) In humans
1) 3 days
2) 3 weeks
- The heart can pump blood BEFORE the cardiovascular system is complete
_______ exchange pump in cell membranes is required for signal transduction and heart contraction
Na+/Ca++
Looping and chamber formation involves conversion of A/P orientation into R/L direction. This process involves _______ to direct R/L patterning
nodal and pitx2
Looping and chamber formation:
1) _______ is restricted to the left ventricle
2) _______ is restricted to the right ventricle
Hand 1
Hand 2
Change from fetal to adult hemoglobin:
- fetal hemoglobin: 2α and _____ units
- fetal hemoglobin: 2α and 2β units
2γ
- transition changes by DNA methylation (6 months)
The _______ in fetal hemoglobin increase hemoglobins affinity for O2 allowing the fetal blood to pull oxygen away from the maternal RBC in the placenta
γ unit
- myoglobin has similar change to compensate for fetal hemoglobin
@ first breath, lung volume enlarges and blood pressure increases in the _______ of the heart
left side
First breath closes the _______, which separates the two atria of the heart
Foramen Ovale
- This bypass was needed to allow oxygenated blood from the placenta to enter circulation
Decrease in prostaglandins immediately after birth causes the _______ to close
ductus arteriosus
- allows fetus to pickup oxygen from placenta
- Prostaglandin is made by the placenta
