keeping people healthy week 1 Flashcards

1
Q

Describe the hormonal changes during pregancny

A

oestrogen is produced by the placenta
hCG increased - produced by placenta-cytotrophoblast
hCG maintains progesterone secretion by corpus luteum
progesterone secretion taken over by placenta - relaxes smooth muscle and increases ventilation
Prolactin levels increase and change mammary glands from ductal to lobular
PTH is increased to increase calcium reuptake
adrenal hormones, cortisol and aldosterone increase
human placental lactogen (LPL) is produced by placenta and stimulates lipolysis and fatty acid metabolism by the woman, conserving blood glucose for the foetus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the physical changes during the first trimester

A
lots of changes and symptoms
extremely high levels of oestrogen and progesterone 
morning sickness
tender and swollen breasts 
elevated pulse rate
mood changes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is detected in a pregnancy test?

A

Human chorionic gonadotropin present from time of conception and can be detected in home pregnancy test about a week after missed period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the physical changes during the second semester?

A
body adjusts to changing hormone levels and symptoms lessen or disappear
more energy
increased pelvic pressure
back pain
may feel kicking
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the physical changes in the third trimester?

A
uterus pushes on diaphragm
ankle, feet and face swell as fluid is retained and circulation slows
hip and pelvic pain
varicose veins 
leakage of colostrum
difficulty sleeping
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What can be done to keep the embryo healthy?

A
healthy diet
avoidance of certain foods
avoid alcohol 
smoking cessation
check drugs and medications
vitamin D supplements 
folic acid
gentle exercise (if not new)
avoid high risk sports
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the causes of spina bifida?

A
lack of folic acid
family history 
some epilepsy medication
genetic conditions
obesity 
diabetes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the effects of spina bifida?

A

weekness or paralysis of the legs
bowel or urinary incontinence
loss of sensation in legs or bottom
many babies will develop hydrocephalus which can cause brain damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the types of spina bifida?

A

Myelomeningocele
meningocele
oculta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe myelomeningocele

A

most serious

spinal cord and meninges push out and create sac on baby’s back

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe meningocele

A

only meninges push out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe oculta

A

most common - opening to spine is small and covered in skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is screened for during pregnancy ?

A

infectious disease
inherited conditions
Down’s, Edward’s or Patau’s syndromes
Abnormalities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What can be used for screening?

A

blood tests

ultrasound tests

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What diagnosis tests can be carried out during pregnancy?

A

amniocentesis or chorionic villus sampling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the placenta

A

connection between mother and foetus
physical attachment of embryo to uterus
bringing feel/ maternal circulations to proximity
allow exchange of gases
foetal growth and development depend on placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the chorionic placenta

A

chorionic plate is covered by avascular glossy amnion
the vessels that can be seen on this plate are chorionic vessels
chorionic vessels branch from the umbilical cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the basal plate

A

maternal side
top layer of surface adheres to the placenta after separation from the uterus
endometrial and trophoblast cells and fibrinoid
separated by lobes which roughly shows the underlying villous tree

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the precursor to the placenta?

A

cytotrophoblast

trophoblast extensions penetrate in between the uterine endometrial cells

20
Q

Describe stage one of placental development

A

CTB layer differentiates into the inner villous CTB and a non dividing layer called the syncytiotrophoblasts
fluid filled spaces called lacunae begin to develop within the CTB mass

21
Q

What happen in stage two of placental development?

A

some trophoblasts migrate into the endometrium around the uterine spinal arteries
initially maternal blood escapes from the spinal arteries and passes into the lacunae before the mouths of the spiral arteries become blocked by trophoblast plugs
these prevent maternal blood from entering the lacunae or intervillous space for the first 10 weeks of pregnancy

22
Q

Describe stage 3 of placental development

A

placenta and foetus experience no oxidative stress
as the plugs dissolve oxygen tension increases and placenta produces protective antioxidants
changes occur in the endothelial lining of the uterus including cellular growth

23
Q

Describe the villous tree

A

trophoblasts and lacunae start branching
the lacunae are precursors to intervillous space
the branches of the trophoblast become known as chorionic villi
the villous core is known as the stroma and is mostly fibroblast cells
capillaries develop within the villi
cCTB layer is only present in early pregnancy

24
Q

Describe trophoblast invasion

A

trophoblasts begin the invade into the maternal endometrium, myometrium then spiral arteries
this remodels the arteries from being low flow, high resistance to high flow, low resistance

25
Q

Describe placental transport

A

fatal blood flows through the umbilical arteries to the capillaries of the villi and then returns through the umbilical vein to the foetus
a very short distance separates the foetal and maternal circulations
oxygen and substances are transported or diffuse into foetal blood and waste into maternal blood

26
Q

Describe nutrient transfer in uterus

A

O2 diffuses
glucose - facilitated diffusion
amino acids - active transport
fatty acids - highly regulated

27
Q

What is the inducer?

A

one cell population / tissue acts on another tissue (the responder_

28
Q

Describe the development of the neural tube

A

gastrulation week 3
ectoderm makes epidermis and nervous systems
development of noto cord
transient pattering structure
role in molecular signalling
inductive relationship with overlying ectoderm
signals from the note cord (mesoderm) induce development of neural plate in overlying ectoderm
signals involve noggin and chordin

29
Q

What does noggin do?

A

inactivates BMP4 which causes patterning of noto cord and somites

30
Q

What does chords do?

A

BMP antagonist - cranial mesoderm is dorsalised

31
Q

Describe the formation of the neural plate

A

appearance of the noto cord and mesoderm induces the overlying ectoderm to thicken and form the neural plate
cells of the plate make up the neuro-ectoderm and is the initial process of neurulation - formation of the neural tube

32
Q

Describe folding of the neural plate

A

lengthen and lateral edges elevate
form the neural folds
depressed mid region forms neural groove
the folds approach each other in the midline and fuse forming the neural tube
tube sinks in and overlying ectoderm repairs
neural tube forms brain and spinal cord
neural tube closes by day 22

33
Q

Describe bending of the neural tube

A

cell wedging - microtubules and microfiliametns change cell shape
Hinge points - median hinge points, dorsolateral hinge pint
extrinsic forces - pushing of the surface ectoderm, adhesion point with notocord

34
Q

Describe the closure of the neural tube

A

fusion begins in the cervical region and proceeds in cephalic and caudal directions
open ends of tubes form anterior and posterior neuropores
these connect with the overlying amniotic cavity
closure occurs in week 4
somites also form along side neural tube

35
Q

Describe sonic hedgehog signalling

A

one of the most potent inductive signals

part

36
Q

Describe signalling involved in the differentiation of the neural tube

A

noto cord continues to exert inductive influence
presents the SHH to neural tube
the ventral most cells respond to this signal - make the floor plate of the neural tube
floor plate then makes its own SHH - responsible for development of motor neurones on each side of the tube

37
Q

Describe the role of the PAX genes

A

pumps from the ectoderm up regulate PAX3 and PAX7 so the roof plate forms, sensory neurons develop here
when SHH induces the floor plate, PAX3 and 7 expression is repressed. This allows cells to adopt ventral fate

38
Q

Describe patched and smoothened signalling

A

patched inhibits smoothened - this stops downstream signalling cis Gli which would eventually traduce SHH signs
If SHH binds to patched, removes inhibition, unreguates downstream pathway and controls effector genes ub the SHH pathways

39
Q

What can cause defects?

A

environmental
chromosomal
multifactorial genetic predisposition
most unknown

40
Q

What is a teratogen?

A

an agent that can disturb the development of the embryo or foetus

41
Q

What effects can teratogens have during weeks 1-2?

A

teratogens will either have no effect or conception will be aborted

42
Q

What effects can teratogens have during weeks 3-8?

A

organs are being established
each organ has its own period of maximum sensitivity
type of defect seen depends on time

43
Q

What effects can teratogens have during weeks 9-38 of pregnancy?

A

functional deficits and minor abnormalities depending on stage

44
Q

What sorts of things can be teratogens?

A

environmental
drugs and chemicals
industrial pollutants
hormones

45
Q

What are the effects of foetal alcohol syndrome?

A
facial deformities
low birth weight
small head
developmental delay 
poor coordination
poor socialisation
poor memory