with correct answers provided
what are endothermic amniotes? - ✅✅animals that are able to maintain a fairly constant body
temperature through internal heat production
-> separates mammals from birds/reptiles
why are physiological changes required at birth? - ✅✅need specific and fully organized neurological/
reflex paths
9 physiological changes required at birth? - ✅✅1. fully organized neurological/reflex paths
2. endocrine function
3. epidermal function (barriers)
Loss of placenta results in an increase in:
4. heat generation
5. intestinal function
6. liver function
7. renal function
8. lung function
9. cardiovascular changes driven by the need for changes made by loss of placenta
maternal blood in placenta - ✅✅supplied by 80-100 spiral endomaterial arteries
placenta types in mammals - ✅✅monotrenes- egg laying so no placenta
marcupials and placental- contain placenta
human placenta - ✅✅- maternal blood in direct contact with syncytial cells
- 12cm radius
- 2cm thick
, - sections called cotyledon
where does the transfer of material occur in the placenta? - ✅✅over syncitiotrophoblast
8 main roles of the placenta - ✅✅1. transfer of gases
2. transfer of nutrients
3. transfer of urea and NH3
4. transfer of IgG to fetus- mediated by neonatal Fc receptor (FcRn)
5. circulatory reservoir
6. heat transfer sink
7. immune modulator
8. hormone production
Immune modulator- NK cells - ✅✅- high number of natural killer cells in the uterus. loss of NK control
results in the destruction of the placenta
why might immune modulation be needed in the fetus and placenta? - ✅✅they contain genetic
material from the father so could be seen as foreign. need to suppress an immune response
synctiotrophoblasts in placenta - ✅✅inhibit maternal NK cells via macrophages, inducing TGF beta 1
(immunosuppressant)
host-vs-graft reaction in uterus - ✅✅suppression via NeurokininB
localized effect on maternal immune cells
what are trophoblasts and what is their interaction with immunity? - ✅✅they provide nutrition to an
embryo
they express nonclassical MHC molecule HLA-G = does not activate T cells
5 hormones produced by the placenta - ✅✅1. chorionic gonadotrophin