S2M3 Physiology Wright Fetal And Neonatal Physiology

Front 1

Which hormones can the fetus make?

Which can it NOT make?

Back 1

Fetus can make androgens

Fetus CANNOT make progesterone or estrogens

Front 2

What can the placenta make?

Back 2

The placenta can take cholesterol and make progesterone. This can be transporter across to the fetus for it to make cortisol and aldosterone

Placenta also produces estriol and its primary estrogen

Front 3

Fetal hormones Insulin and glucagon are fuctional when?

Back 3

pancreateic islets are functional by 14 weeks and have low secretion rates b/c abundant from mom.
Fetal insulin contributes to building fat.

Front 4

Is adult GH present in a fetus?

Back 4

No, instead other similar hormones IGF 1 and 2 play important roles

Front 5

Describe prolactin levels in fetal plasma and amniotic fluid.

Back 5

High

Front 6

Describe fetal hormones T3, PTH-related peptide and ACTH

Back 6

T3 is not needed , PTH-RP is high to keep fetal plasma Ca levels high. ACTH stimulates production of steroids by fetal adrenal cortex and allows neonate to release cortisol during the stress of childbirth

Front 7

What is the important action of glucocorticoids during fetal life?

Back 7

promotion of glycogen storage (esp in last month)

Front 8

What is the important action of insulin during fetal life?

Who makes the insulin? Mom or fetus?

Back 8

Helps fetus uptake glucose and AA
Stimulates lipogenesis

Fetus!! B/c insulin cannot cross placenta

Front 9

What is the important of fetal IGFs? (sommatomedins)

Back 9

critical for normal growth and development and are present in fetal circulation by the end of the first trimester.

Front 10

What week of development does scalp hair develop, fetus is active and cardiac chambers are well developed?

Back 10

Week 16

Remember week 3 is when the 2 chambered primitive heart is developed.

Front 11

What week of development are there primitive respiratory-like movements?

Back 11

Week 24

Front 12

What week do fingernails appear and if delivered with optimal care could survive? (Also testes descend)

Back 12

WEEK 28!!

Front 13

Describe the organs responsible for erythropoiesis in order of their function.

Back 13

Yolk sac - wk 3
Placenta - wk 3
Endothelium- wk 4
Mesenchyme- wk 4
Liver 4-5 week
BONE MARROW by the end of the 1st trimester and the dominant source by the 3rd trimester
-spleen and lymphoid tissue: end of 1st trimester

Front 14

When do kidneys start working?
Why are they so important?

Back 14

They begin producing urine during the 2nd trimester.

Urine production replenishes amniotic fluid. Lack of amniotic fluid= oligohydramnios

Front 15

When does GI tract start working?

Is this futile?

Back 15

Starts working in 3rd trimester.

Very futile b/c fetus doesn't digest or absorb anything; it only drinks amniotic fluid

Front 16

When does CNS work?

Describe post-natal development.

Back 16

develops around 3rd of 4th month

Nervous system continues to develop after birth and also continues to myelinate long fiber tracts

Front 17

Respiratory system has 4 phases of development, what are they?

Back 17

-psudoglandular period
-canalicular period
-terminal sac period
-Alveolar period

Front 18

When does first pulmonary tissue appear?
-initial branching of bronchial tree?
-Pulmonary bronchial tree complete?

Back 18

-3rd week

-4-6 weeks

- ~25 weeks

Front 19

what is the correlation between glucocorticoids and lung development?

Back 19

You must have glucocorticoids for type 2 alveolar cells to make surfactant.
-Preemies need glucocorticoids

Front 20

Who makes T3/T4 mom or baby?

Back 20

Mom does in the first trimester and baby will begin produces TSH and T4 early in the second trimester.

Front 21

Untreated hypothyroidism during fetal development can lead to what disease?

Back 21

Cretinism

Front 22

What process uses the majority (15-20%) of the fetus' metabolic energy requirements?

Back 22

Protein synthesis

-skeletal muscle and growth of organs requires tremendous amounts of energy and protein synthesis

Front 23

Can the fetus make FA?

Back 23

Yes! by 3rd trimester the fetus is making and storing lipids. The increase in fetal albumin facilitates transport of fatty acids across the placenta

Front 24

What does the fetus store lipids as?

Back 24

Stores lipids as TAG in white and brown adipose during the last 2 months of gestation

Front 25

Regarding fetal lipid metabolism answer the following:
1.) what serves as substrates for producing FA?
2.) Role of insulin?

Back 25

1.) glucose and lactic acid are substates

2.) Insulin stimulates lipogenesis and augments the transport of glucose and lactate across the plasma membrane.

Front 26

Movement from the uterus to the outside world require what adjustments?

Back 26

1.) colder environment
2.) Hypoxia
3.) Hypoglycemia (removal of constant supply of nutrients)

Front 27

Describe the First breath.

Back 27

No air in the lungs!!
Activation of medullary respiratory centers and there is a VERY strong respiratory effort b/c the alveoli are collapsed and there is high surface tension.

Front 28

During the first breath, you only inflat your lungs to around 40 mL tidal volume, why is this okay?

Back 28

You are only trying to establish a residual volume for the 2nd breath. Each subsequent breath becomes easier and easier.
-reduced effort due to reduced surface tension and surfactant
-Substantially reduced transpulmonary pressure within the first hour of life

Front 29

After the first breath, O2 levels will obviously increase and alveoli inflate with air. Describe the changes in resistance and flow?

Back 29

As alveoli inflate, resistance will decrease rapidly and mean pulmonary pressure drops drastically.
This will increase FLOW to lungs

Front 30

Increased flow to the lungs close foramen ovale how?

Back 30

After resistance in lungs decrease, this will also decrease the pressure in the right atrium. Simultaneously, blood is now entering the left atrium and the pressure exerted there is now greater than in the right atrium. This encourages closure of foramen ovale valve.

Front 31

What causes the ductus arteriosus to close?

Back 31

During fetal life, PGE2 kept it patent but after parturition, PGE2 decreases. (also, NE, ACh and bradykinin act as vasocontrictors)

Front 32

Why is glycogen phosphorylase and G6P activated shortly after birth?

Back 32

To utilize glycogen stores in cardiac muscle after birth to keep newborn alive.

Front 33

Hypoglycemia shortly after birth will decrease insulin release. How does the baby remedy this?

Back 33

Hypoglycemia and increased EPI stimulate glucagon release. This shifts carb metabolism from glycogenesis to glycogenolysis to PRODUCE glucose in the baby.

Front 34

Newborns have High metabolic rates that contribute to increased ventilation and CO and production of acidic metabolites. Failure of what organ system could spell trouble?

Back 34

Impairment of kidney development or renal function can cause severe metabolic acidosis. (cannot clear H's)

Front 35

If breast milk has low Vit D and Ca, __________?

If breast milk has low levels of vit C, ________?

Back 35

Rickets

Scurvy

Front 36

How does infant respond to cold stress?

Back 36

Release of TSH
Release EPI
convert T4-->T3 which stimulates production of uncoupler

EPI activates PKA which hydrolyzes TAGS and produces FA.

Front 37

How does brown fat mediate thermogenesis?

Back 37

Free FA move into mito and cause opening of H channels of uncoupler.

-Non-shivering thermogenesis.