Human Development Flashcards
1
Q
Difference between:
a) Exocrine and endocrine glands
b) Exocrine and endocrine secretions
A
a) Exocrine - secrete via duct, Endocrine - direct into circulation
b) Exocrine - Outwith body, Endocrine - within body
2
Q
Describe action and give example:
a) Paracrine
b) Autocrine
c) Neurocrine
d) Endocrine
e) Neuroendocrine
A
a) Acts on cell close by e.g. His from mast cells
b) Acts on same cell e.g. interleukins
c) Electrical signal passed on via synapse e.g. NT
d) Produce 1 prt body, travel in blood e.g. insulin
e) Elec signal passed on via circulation e.g. dopa inhibition of prolactin release
3
Q
What is the difference between alpha and beta chain in glycoprotein hormones?
A
Alpha - Species specific
Beta - Hormone specific
4
Q
What glycoprotein hormone is released from placenta?
A
Human Chorionic Gonadotropin
5
Q
Function and example of:
a) Mineralocorticoid
b) Glucocorticoid
c) Sex steroid
A
a) Affect H20 + electrolyte balance e.g. aldosterone
b) A’’ carb + protein metabolism e.g. cortisol
c) Sexual characteristics e.g. oestr, testos
6
Q
What types of hormones circulate in :
a) Free form?
b) Bound form?
A
a) Catecholamines, proteins/peptides
b) Thyroid + steroid hormones
7
Q
What 2 types of hormones are stored in secretory granules/vesicles?
(How released)
A
Catecholamines + Peptides
Release via exocytosis, triggered by Ca2+
8
Q
What are the 5 types of hormone release? + example
A
Pulsatile - episodic release e.g. LH/FSH hourly release
Circadian - based 24hr cycle e.g cortisol
Diurnal - synchronised to day/night cycle more animals
Infradian - Longer than 24hr cycle e.g. menstrual cycle
Seasonal - More animal e.g. prolactin
9
Q
What types of hormones are:
a) Hydrophilic?
b) Lipophilic?
How does this affect binding to plasma proteins?
A
a) Catecholamines + Peptides
b) Thyroid + Steroid hormones
Hydrophilic x bind, lipophilic binds
10
Q
How many parts does the pit. gland have?
What are they made up of?
A
Ant lobe (Adenohypophysis) - Pars distalis + tuberalis Neuro-intermediate lobe - Pars intermedia + nervosa Post lobe (neurohypophysis) - Pars nervosa + infundibulum
11
Q
What is another name for pit. gland?
A
Hypophysis
12
Q
Which part of the pit gland is not well developed in man?
A
Neuro intermediate lobe
13
Q
What is the growth hormone inhibiting hormone?
A
Somatostatin
14
Q
What is the:
a) Releasing hormone
b) Inhibitory factor/hormone
of prolactin?
A
a) TRH
b) Dopamine
15
Q
What is the main cell type of ant pit?
What do they produce?
A
Somatotrophs
Growth hormones
16
Q
What hormone suppresses menstrual cycle in lactating mother?
A
Prolactin
17
Q
Via what receptors does dopamine inhibit prolactin?
How would you treat them in hyperprolactinemia?
A
D2 receptors
Selective D2 agonists e.g. bromocriptine, cabergoline
18
Q
What types of somatostatin analogues work better on:
a) Type 2 somatostatin receptor
b) Type 5 somatostatin receptor
Which one is better?
A
a) Octreotide + Lanreotide
b) Pasireotide
Type 5, pasireotide
19
Q
What carrier molecule is associated with:
a) Oxytocin?
b) ADH?
A
a) Neurophysin I
b) Neurophysin II
20
Q
What happens to colloid space in:
a) Underactive thyroid?
b) Overactive thyroid?
A
a) Large colloid spaces
b) Little/no colloid spaces also hyperplasia of follicular cells
21
Q
What happens to fetus if thyroid hormones are not properly delivered?
A
Cretinism
22
Q
What is a goitrogen?
A
Substances disrupt production of thyroid hormones by interfering with iodine uptake in thyroid gland
Increase TSH secretion to form goitre
23
Q
What is the additional effect of propylthiouracil?
A
Prevents peripheral conversion of T4 to T3
24
Q
How much of the bodies iodine is found in the thyroid gland?
A
60-65%
25
What defines iodine deficiency?
Less than 50 micrograms a day
26
Where are adrenal glands located and shape?
On top of kidneys
RHS - pyramidal
LHS - oval shape
27
What are the layers of the kidney from outside to in?
Zona glomerulosa
Zona fasciculata
Zona reticularis
28
What does the medulla of the adrenal gland produce?
| What percentage?
Adrenaline - 80%
| Noradrenaline - 20%
29
What does the zona glomerulosa produce?
| What enzyme does it lack and why?
Mineralocorticoids e.g. aldosterone
| 17-alpha hydroxylase, x produce cortisol
30
What does the zona fasciculata produce?
| What enzyme does it lack and why?
Glucocorticoid e.g. cortisol
| Aldosterone synthase, x produce aldosterone
31
What does the zona reticularis produce?
| What enzyme does it lack and why?
Adrenal androgens eg. androstenedione, DHEA (a little cortisol)
Aldosterone synthase
32
What are all steroid hormones derived from?
Cholesterol
33
What is an example of an aldosterone antagonist?
Spironolactone
34
What is affected in these types of hypothyroidism?
a) Tertiary
b) Secondary
c) Primary
d) Resistance
a) Hypo/TRH
b) Pit. gland/TSH
c) Thyroid/T3+T4
d) Periphery/alpha thyroid receptors
35
Where is the pituitary gland located in the skull?
| What is it called?
Sphenoid bone
| Pituitary fossa
36
What structure is located above pit. gland?
Optic chiasm
37
What would you test for pituitary hypo function?
Measure pituitary hormone and target hormone
38
What are the 2 ways pituitary tumours can be categorised?
| Sub categories?
Size - microadenoma (<10mm)/macroadenoma (>10mm)
| Functioning - endocrine syndromes/non-functioning
39
What are 3 examples of diseases caused by non-functioning macroadenoma of the pit gland?
Cushing's disease
Acromegaly
Prolactinoma
40
How are majority of:
a) Macroadenoma of pit gland
b) Microadenoma of pit gland treated?
What is used in regrowth?
a) Surgically (trans-sphenoidal)
b) Medically/Conservatively
Radiotherapy
41
What type of pit gland tumour can be treated well medically?
Prolactin secreting tumours
42
When would radio-iodine therapy be avoided in the treatment of hyperthyroidism?
Thyroid eye disease
43
What % of thyroid nodules are benign?
90%
44
What is the main type of thyroid cancer? (+ %)
| What is the prognosis?
Papillary thyroid cancer, 85%
| 5 yr survival >98%
45
What is a pheochromocytoma?
Tumour of adrenal medulla
46
Meaning of 'gravidity' (relation to pregnancy)
No times uterus has been pregnant, inc current pregnancy
47
Meaning of 'parity' (relation to pregnancy)
No babies she has given birth to at 24 weeks or later, born alive/dead
+ superscript of other pregnancies up to
23 weeks (miscarriage, ectopic, TOP)
48
What blood pressure values are used for hypertension in pregnant women?
140/90 - hypertension
| 160/110 - severe hypertension
49
What is pre-eclampsia (PET) in pregnant women?
| When does it usually occur?
Raised BP 140/90 + Protein in urine
| After 20 weeks
50
Why should a pregnant women not be on her back more than a min?
Impaired venous return via IVC - supine hypotension
51
What observation chart is used in obstetrics?
MEOWS
52
What pregnancy stage is dating scan used?
| What fetal measurement is used to calculate expected date of delivery?
11-13 weeks
| Crown-rump length of fetus, calculates gestational age
53
What is the symphyseal- fundal height?
| What body parts are included?
Assess growth of fetus + growth of uterus
Pubic symphysis - Fundus (top if uterus)
Cm
54
What stage of pregnancy is symphyseal- fundal height measured?
What is expected growth?
Every antenatal visit from 24 weeks
| Same amount cm as weeks pregnant +/- 2cm
55
What is the name of the division of the testicles? (anatomically)
What is contained within them?
Lobules
| Seminiferous tubules
56
What 2 types of cells line the seminiferous tubules of the testicles?
What do they do?
Spermatogonial stem cells - gamete (sperm) production
| Sertoli cells - support, nutrit, protec, secretory, excretory
57
How much sperm is produced during spermatogenesis?
| How long does the whole process take?
Approx 120 million p/day // 1500/sec
| 72 days
58
What is spermiogenesis?
Conversion of spermatid to mature sperm
| Becomes longer + thinner, mito go around neck of sperm
59
What are the names of the different parts during spermatogenesis? (the different cell types)
Spermatogonia, Primary + 2ndary spermatocytes, Primary + 2ndary spermatids, spermatozoa (mature)
60
What is the structure of a mature sperm cell?
Head - nucleus, acrosome
Neck - mito
Tail
61
What compartment of the seminiferous tubules are mature sperm cells produced?
Luminal compartment
62
What comprises the interstitial compartment of the seminiferous tubules of the testicles?
Basal spermatogonial stem cells
| Interstitial cells of Leydig
63
Why are there 2 compartments in the seminiferous tubules of the testicles?
Separates newly formed sperm cells
| Protect from immune system from being seen foreign
64
What cells in seminiferous tubules of the testicles remove degenerate sperm cells?
Sertoli cells
65
What hormones do the Sertoli cells of the seminiferous tubules of the testicles produce?
Inhibin, ABP (androgen binding protein)
| AMH (anti Müllerian hormone), growth factors
66
What hormone do the interstitial cells of Leydig secrete?
| What is it's actions?
Testosterone, C19
| Anabolic, primary + 2ndary sexual character, libido, stimulates sertoli cells + spermatogenesis
67
What hormones inhibit:
a) FSH
b) LH
production in males?
a) Inhibin
| b) Testosterone
68
What are the 4 stages of sperm transport (to get fertilised)?
Short Descrip
Ejaculation
Cervix - mucous barriers + crypts = sperm resevoir
Uterus + tubes - mild contraction to propel towards egg
Ampullary portion of tube - fertilisation
69
What is sperm capacitation?
| What happens?
Sperm becomes 'hyperactivated', more speed
4 hours after ejaculation
Cholesterol loss + Ca2+ influx
70
What happens to sperm as it reaches the oocyte?
Interaction of ZP3 protein on oocyte membrane
Acrosome reaction releases enzymes
Facilitates penetration
71
What enzymes are contained within acrosome of sperm cell?
Hyaluronidase
| Acrosin enzymes
72
How is the oocyte activated after penetration from sperm cells?
Release of cortical granules to block polyspermic penetration
Resumption of meiosis
73
What factors can affect sperm production?
Excess testost intake
Environ
Air pollution/Smoking
Food chain pollution
74
What is the mechanism that can affect sperm production?
Free O2 radicals e.g. O2, H2O2, OH
75
What is the NICE definition of infertility?
Woman of reproductive age who x conceived after 1 year of unprotected sexual intercourse
76
What 3 factors can affect chances of pregnancy?
Previous pregnancy
Duration less than 3 years
Age less than 30 years
77
How would you test ovulation?
Midluteal progesterone, 7 days before next expected period
78
How would you test semen?
Test: concentration, mobility, morphology
79
How would you test ovarian reserve?
Early follicular FSH
Antral follicle count (AFC) - measuring size of follicles
Anti-Mullerian Hormone (AMH)
80
Where is AMH produced in females?
| When can it be measured (to test for ovarian reserve)?
Produced by granulosa cells from pre-antral + antral follicles
Measured anytime in cycle
81
What is anovulation?
| What are the 3 types?
Ovaries x release oocyte during menstrual cycle
Group I: hypothalamic amenorrhoea/ hypogonadotropic hypogonadism, 20%
Group II: hypothalamic-pituitary-ovarian dysfunction
(predominately polycystic ovary syndrome)
Group III: ovarian insufficiency.
82
What 3 common drugs are used to treat anovulation?
Clomiphene citrate - selective oest receptor
Letrozole - aromatase inhibitor
Gonadotrophins
83
What is azoospermia?
| What are the 2 types?
Semen present but no sperm
Obstructive - normal spermatogenesis, normal sized testes + FSH levels
Non-obstructive - impaired spermatogenesis, small testes + raised FSH
84
What are the common causes for the 2 types azoospermia?
Obstructive - post infection/vasectomy, congenital absence of vas deferens
Non-obstructive - testicular failure,
85
What is the common treatment for azoospermia?
Sperm retrieval
Percutaneous epididymal sperm aspiration (PESA)
Testicular sperm extraction (TESE)
86
What is ICSI?
Intracytoplasmic Sperm injection
| Part of IVF to get sperm ready
87
When does a fetus acquire legal rights?
At birth
88
When was Abortion Act established?
| What criteria have to be met?
1967
2 registered practitioners of opinion, 1/4 grounds exists
Carried out by Registered medical practitioner
Procedure performed in an approved place
Notified to Chief Medical Officer of DoH
89
When was the Abortion act amended?
1990
90
What abortion can be carried out at home?
| How many weeks of pregnancy
First 10 weeks
91
What is ART?
Assisted Reproductive Technologies
| e.g. IVF, artificial insemination, surrogacy
92
What is preimplantation genetic diagnosis(PGD)?
Cell from an embryo at 8-cell stage of development, Around 3-days old, + testing it
93
In the 1st 5 days of human development, what is formed?
Blastocyst
94
What is contained in a blastocyst?
Trophoblast layer - embryonic contribution to placenta
| Inner cell mass - totipotent cell types
95
What does the inner cell mass of the blastocyst divide into?
Epiblast - ecto/meso/endoderm, amniotic membrane
| Hypoblast - Heuser's membrane
96
When is the heart and brain visible in a developing fetus?
Week 2
97
When does the heart start to beat?
Week 3
98
What is the embryonic development period in human development? (What weeks)
Weeks 3 -8
| Most organs develop
99
What process leads to the germ layers in human development?
Gastrulation
100
What organs do the 3 germ layers give rise to?
Ectoderm - epidermis, nervous system
Mesoderm - skeleton, muscle, dermis, kidney, blood
Endoderm - gut, liver, pancreas, lungs
101
Where do the brain and spinal cord develop on the ectoderm?
On the midline
102
What is the name of:
a) Anterior
b) Posterior
when looking at fetus?
a) Rostral
| b) Caudal
103
What are 3 examples of endodermal defects?
Lung aplasia - no lungs
Oesophageal atresia/fistula
Omphalocele
104
What are the 3 divisions of the mesoderm?
Paraxial mesoderm
Intermediate mesoderm
Lateral plate mesoderm - somatic + splanchnic mesoderm
105
What structures arise from lateral plate mesoderm?
Dermis of skin, Limb Skeleton, Heart, Blood vessels, Blood, connective tissue
Mucosal + muscle layers of gut
106
What structures arise from intermediate mesoderm?
Kidneys, M + F reproductive systems
107
What structures arise from paraxial mesoderm?
Vertebrae + ribs, muscles of body, dermis of skin (back)
108
What are the cell types in the neural crest?
| What can they arise from?
```
Multipotent
Cranial from brain
Vagal from cordal hindbrain
Trunk
Sacral
```
109
What is Hirschsprung's disease?
Failure of vagal/sacral neural crest to migrate ==> post regions of gut
Bowels contents build up proximal to affected region, causing it to expand
110
What is Liebenburg syndrome?
Abnormal expression of arms so have leg like characteristics
| Mutation in Pitx1 gene that usu goes to leg
111
What viruses represent acronym TORCH?
```
Toxoplasma parasite
Other viruses e.g. parvovirus
Rubella
Cytomegalovirus
Herpes
```
112
What is a teratogen?
Agent that causes an abnormality following fetal exposure during pregnancy
113
How many births are affected by fetal alcohol syndrome?
1 in 500 live births
114
What is oligohydramnios?
Too little amniotic fluid
115
What are amniotic bands?
Bands of amnion (inner lining of amniotic sac) peel away from sac and attach/wrap around prts of fetus
116
What is the main concern for premature babies?
Lungs x fully developed, neonatal respiratory distress syndrome
Cut off survival 22 weeks
117
What week of pregnancy does the neural tube close in?
Week 3
118
Why can't a baby survive before 22 weeks?
Lung x developed alveoli
119
What is reduced penetrance?
Proportion of mutation carriers who manifest clinical signs of condition
If some peeps mit mutation X develop features of disorder, condition has reduced/incomplete penetrance
Oft seen in hereditary cancer syndromes
120
What is variable expressivity?
Degree condition is expressed (ie severity) in person
Variable between families /within families
Oft seen in chromo deletion / duplication syndromes
121
What are the 2 parts of the ovaries?
| What do they contain?
Medulla - blood vessels
| Cortex - follicles at diff stages of development
122
What is ovarian reserve?
| What's the normal amount in a healthy woman?
Number of follicles visible in ovary at any given time
| 10-20 follicles
123
What is atresia in the ovaries?
Breakdown of ovarian follicles which contains an oocyte
124
What are the 3 phases of the Ovarian cycle?
Phase 1 - Follicular phase, Days 1-10
Phase 2 - Ovulatory phase, Days 11-14
Phase 3 - Luteal Phase
125
What happens during Phase 1 of Ovarian cycle?
Hormones signal causes 10-20 follicles to grow
| Growing follicles produce estrogen
126
What happens during Phase 2 of Ovarian cycle?
Dominant Follicle causes signif rise of oestradiol
follow by LH surge
Follicle wall thins + ruptures
Oocyte enters abdominal cavity near fimbriae of fallopian tube
127
How is the oocyte propelled along the fallopian tubes?
By cilia and fallopian tube contractions
128
What happens during Phase 3 of Ovarian cycle?
After ovulation, hemorrhage into remains of follicle usu occurs
Structure corpus hemorrhagicum forms
Develops into corpus luteum (yellow body)
129
What reproductive hormones are present in women?
| What do they do?
Gonadotropins - FSH (maturation), LH (release) act on ovaries
Oestrogen - maturation of reproductive organs, menstruation, + pregnancy
Progesterone - helps maintain uterine lining
130
What are the suspensory ligaments of the uterus?
Broad ligament
Uterosacral ligaments
Round ligaments
Lateral (cardinal ligaments)
131
What are the functions of the uterus?
```
Transports to tubes for fertilization
Provides suitable environment for
- implantation of the embryo
- nourishment of embryo + fetus during pregnancy
Mechanical protection of fetus
Expels mature fetus at end of pregnancy
```
132
What are the 3 segments of the fallopian tube?
Infundibulum - lots fingerlike projections - fimbriae
- inner surface covered with cilia
Ampulla
Isthmus
133
What are the 5 layers of the fallopian tube (outside to in)
```
Tunica serosa
Tunica muscularis
Tunica submucosa
Tunica mucosa
Lumen
```
134
What part of the fallopian tube has a bigger lumen?
Ampulla
135
What is the embryology of the ovary?
Primordial germ cells (PGC) emerge in wall of yolk sac
as cluster of about 20 cells
Synchronised PGC migration to genital ridge
Sex differentiation from a bipotential gonad
At genital ridge – mitosis up to 8 weeks
Mitosis + meiosis from 8 to 28 weeks
20 weeks gestation ~ 7 million germ cells
From 20 weeks, atresia dominates
At birth, there are about 1-2 million germ cells
During 1st yr of life, ovaries migrate ==> true pelvis
136
What happens during oogenesis and folliculogenesis?
At birth all primordial oocytes (inside primordial
follicles) arrested at Prophase 1 of Meiosis I
Most primordial follicles undergo atresia from birth to menopause
Meiosis I makes 2ndary oocyte, 1st polar body (dies)
2ndary oocyte arrests at metaphase II of Meiosis II
Ovulation occurs
Meiosis II only completes when egg fertilized, 2nd polar body extruded to prevent triploidy
All happens alongside follicular development and
ovulation
137
How long can folliculogenesis take?
300 days+
138
What is the climacteric (in relation to menopause)?
Period of time around last menstrual period
| AKA perimenopause
139
What is the difference between continuous and sequential HRT (in relation to menopause)?
Continual - oest + progest taken every day, same levels for rest of life
Sequential - oest taken every day, progest every 2 weeks
140
In the follicular stage of the ovarian cycle, what are the different stages (diff cell types)?
Primordial follicle, Primary follicle, 2ndary follicle, Tertiary follicle
141
Levels of which hormone spike before ovulation?
| How many hours before?
LH
| 34-36 hours before
142
Where is the oocyte released into during ovulation?
Abdominal cavity near fimbriae of fallopian tube
143
What hormones does the corpus luteum produce?
Oestrogen and Progesterone
144
What happens to corpus luteum when:
a) Egg is fertilised?
b) Egg x fertilised?
a) Continues produce hormone until placenta formed
| b) After 2 weeks, degenerates into corpus albicans, x produce hormones
145
What hormone is present that prevents corpus luteum from degenerating when an egg is fertilised?
Human chorionic gonadotropin (hCG)
146
What are the 3 stages of the uterine cycle?
Menstrual phase
Proliferative phase
Secretory phase
147
In what phase of the uterine cycle does growth of the follicles occur?
Menstrual phase
148
What phases of the uterine cycle does the growth of the endometrium occur?
When does it have good vasculature?
Proliferative + Secretory phase
| Secretory phase
149
What are the 2 layers of the endometrium?
| What layer sloughs off during menstruation?
Stratum basalis + functionalis
| Stratum functionalis
150
When during the uterine cycle are progesterone levels at their highest?
When the walls of the endometrium are the thickest
151
What zone of adrenal gland is regulated by renin-angiotensin system?
Zona glomerulosa
152
What are 3 common causes of chromosomal aneuplodies?
Due to malsegregation either:
Gonads during meiosis ==> abnormal gametes
Mitosis in germline ==> mosaicism in gonad
Mitosis in early embryo ==> mosaicism in embryo
153
What is Robertsonian translocations?
Fusion of 2 acrocentric chromos - 13,14,15,21,22 (long arms fuse)
Prevalence 1 in 1000
154
What are reciprocal translocations?
Exchange of material between 2 non-homologous chromos
| Prevalence 1 in 500
155
What are some invasive methodologies for prenatal testing?
Chorionic villus sampling (CVS)
Amniotic fluid sampling
Fetal blood sampling
156
What are some non invasive methodologies for prenatal testing?
Peripheral maternal blood sampling e.g. biochem screening
| Analysis of free fetal DNA in maternal circulation (NIPT & NIPD)
157
What is the difference between:
a) Genetic testing
b) Genetic prenatal screening
in prenatal genetic tests?
a) sample from pregnancy for presence of specific disorders, invasive techniques, produces diagnosis
b) Risk figure of fetus having certain abnormalities, x diagnosis, +ve results follow up by specific diagnostic test
158
Antenatal testing for what conditions are offered routinely to pregnant women?
Infectious diseases - Hep B, HIV, Syphilis
| Thalassemia
159
When is the fetal anomaly scanned carried out? (What stage of pregnancy?)
18-21 weeks
160
From what weeks of pregnancy is screening for Down syndrome. Edward's + Patau's syndrome offered?
What screenings can patients choose from?
10-14 weeks
| All 3 conditions, Down syndrome only, Edwards' + Patau only, No screening
161
What is the definition of:
a) Preconceptual?
b) Periconceptual?
a) 1-3 months prior to conception
| b) Immediately prior to conception + early gestational phase
162
What weeks are the different trimesters in pregnancy?
1st - 0-13 weeks
2nd - 14-26 weeks
3rd - 27-40 weeks
163
What is:
a) Anencephaly?
b) Spina bifida?
a) Incomplete closure of upper end neural tube (x brain)
| b) Incomplete closure of spinal cord (split spine)
164
What are the folate recommendations in UK for women planning pregnancy?
400 micrograms per day until 12 weeks postconceptually
165
What are some maternal adaptations to meet increased Ca requirements?
↑ intestinal absorption of dietary Ca
↑ reabsorption Ca by kidneys ==> enhanced retention
↑ bone turnover to release Ca
166
What are some maternal adaptations to meet increased Fe requirements?
Amenorrhoea, ↑ absorption of dietary non-heme Fe, mobilisation of maternal stores
Fetus acts ‘parasite’ drawing on maternal stores (risk Fe deficiency anaemia in mothers mit low Fe stores)
167
What is the definition of:
a) Exclusive breastfeeding
b) Weaning
c) Complementary feeding
a) X food/drink (inc H2O) 'cept breast milk (exception vitamin/mineral supplements, medicines)
b) Expanding diet to inc food + drinks other than breast milk/ infant formula
c) Giving foods + liquids in addition to breast milk/infant formula) when these X longer sufficient meet nutritional needs of infants
168
For how long is exclusive breastfeeding recommended for?
| What is the only recommended alternative to breastfeeding for infants <12 months?
First 6 months/26 weeks of infant's life
| Infant formula
169
What are the 3 signs of readiness for solid food (in an infant)?
1. Can stay in a sitting position + hold their head steady
2. Can coordinate eyes, hands + mouth so can look at
food, pick it up + put it in their mouth by themselves
3. Can swallow food, babies who X ready will push food back out
170
Why is there no placental blood flow during the first trimester?
Volume of endovascular trophoblast blocks mouths of arteries so maternal blood x flow into placenta
171
What type of nutrition does the embryo receive in the first trimester?
Histiotrophic nutrition - Nutritional material in spaces between maternal + fetal tissues, derived from maternal endometrium + uterine glands
172
What type of nutrition does the embryo receive when maternal blood flow to placenta is established?
Hemotrophic nutrition
173
What blood vessel carries oxygenated blood to the embryo?
Umbilical vein
174
How many umbilical blood vessels are there?
2 umbilical arteries
| 1 umbilical vein
175
What is the intervillous space in the placenta?
Pools of maternal blood
176
Does the maternal blood and placental blood mix?
No, substances diffuse via placental membrane
177
What are the 3 amino acid transporters across the placenta?
System A - Na dependant, transports small non-essential AA
System L - Na independant, non essential AA exchanged for essential AA
Taurine transporter - cotransport with NA + Chloride
178
What are the isoforms of the 'System A' AA transport in placenta?
Which one is the main contributor to system A activity?
SNAT1, SNAT2, SNAT4
| SNAT1
179
What is:
a) System A
b) System L
regulated by? (AA transport in placenta)
a) Cytokines + hormones
| b) mTOR nutrient sensing pathway
180
What transporter is mostly used for glc transport in second half of pregnancy?
GLUT1
181
How is FA transport carried out in placenta?
MATERNAL: Lipoprotein lipase releases non-esterified FA (NEFAS) from triglycs in lipoproteins (LP)
FETAL: NEFAS transported across trophoblast cells by FA transport proteins (FATP)
182
When are the intestinal villi formed in the fetal alimentary tract?
Intestinal villi formed by 16 weeks
| Well developed by 19 weeks gestation
183
When does the fetus swallow amniotic fluid?
From 12 weeks gestation
184
What hormones does the fetal gut produce?
Gastrin, Motilin, Somatostatin
| Present in gut at 13 weeks, maturity by 24 weeks
185
When are digestive enzymes present in in fetus?
Present by 9-10 weeks
| Maturity at term
186
When does the fetus synthesise insulin?
9-11 weeks
187
What problems does macrosomia cause?
Problems in labour
Increased risk of stillbirth
Caesarean section oft needed
188
How much urine does the fetal bladder produce at term?
500-700ml per day
189
How often does the fetal bladder fill and empty?
Every 20-30 min
190
What is the:
a) Cardiac output to kidneys
b) GFR
in a fetus compared to an adult?
a) 3% (25% in adult)
| b) 50% of an adults
191
Why is fetus urine dilute?
Kidney x concentrate urine due immature ADH
192
What are the contents of the amniotic fluid?
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Urine
Amniotic membrane secretions
Fetal lung secretions
Salivary secretions
Fetal epithelial cells,amniotic cells,dermal fibroblasts
```
193
What structure prevents blood from flowing through fetal liver?
Ductus venosus
194
What is the fetal circulatory response to hypoxia?
Heart rate falls
Resistance in umbilical artery increases
Resistance in middle cerebral artery decreases, protecting flow to fetal brain
Blood flow increased to heart + adrenals
Blood flow reduced to kidneys producing oligohydramnios
195
What cardiac changes occur to baby during delivery of baby?
Cord occlusion decreases right atrial pressure, foramen ovale closes
Inspiration causes vasodilation of pulmonary
artery + decreased resistance in pulmonary
circulation, reducing flow through foramen ovale + ductus arteriosus
196
What does pulmonary surfactant contain?
| When is is secreted in fetus?
70-80% phospholipids
10% protein
10% cholesterol
From 30 weeks
197
What hormone supplement can be given to mothers in premature labour/delivery to help fetal lung development?
What does the hormone do?
Glucocorticoids (usu late pregnancy rise in cortisol)
Stimulates surfactant synthesis + secretion
Epithelial cell differentiation
Lung liquid reabsorption
Increases activity of antioxidants
198
When does HbF start switching to HbA?
| What is the ratio at birth?
28 weeks
| HbF:HbA ==> 80:20
199
What changes happen at delivery when baby has 1st breath?
Pulmonary vascular resistance drops 8-fold partly due to increased arterial pO2
Gas exchange commences
Lung Liquid secretion stops + liquid cleared
Surfactant secretion continues
200
What is the average amount of weight a mother will gain during pregnancy?
30 lbs/ 13kg
201
What injuries can the fetus face if it is too big?
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Shoulder dystocia
Brachial plexus injury
Clavicular/humeral fractures
Cephalohematoma
Subdural hemorrhage
Facial palsy
```
202
What happens to maternal RBC during pregnancy?
Synthesis increases, stimulated by erythropoietin
No increases but apparent anemia due to dilution
Haematocrit falls from approx 40% - 32%
203
What happens to DPG levels in a pregnant woman?
Approx 30% increase, facilitate offload of O2 release to fetus
204
Why do most water soluble vitamins decrease during pregnancy?
Mother's blood volume increases so get diluted
205
How does hCG stimulate maternal thyroid activity?
Binds to TSH receptors of thyroid cells
LH-hCG receptor is expressed in thyroid
Possibly stimulates thyroid activity via LH hCG receptor + TSH receptor
206
What are 3 metabolic actions of human placental lactogen (hPL)?
Maternal lipolysis + increase in maternal (NEFAs) -
Anti-insulin action - increase in maternal insulin
Potent angiogenic hormone - role in formation of fetal vasculature
207
What is function of leptin in pregnancy?
Stimulates placental AA/FA transport
208
Where is leptin:
a) Synthesised?
b) Secreted?
a) Early embryo
| b) Cytotrophoblast cells + syncytiotrophoblast
209
What causes peripheral resistance (+ BP) to fall
| in pregnancy?
Increased vascular endothelial nitric oxide synthesis
Increased endothelial prostacyclin synthesis
Increased compliance of vessels due to structural changes
210
What pulmonary changes occur during pregnancy?
Tidal volume increases
Deep breathing stimulated by progesterone
Respiratory rate unchanged
Expiratory reserve reduced
pCO2 decreases, pO2 increases, pH unchanged (HCO3 falls)
Costal margin + diaphragm altered
211
What is the difference between:
a) Gestational age?
b) Embryonic age?
a) Used clinically, time 0 = 1st day of LMP
| b) Used embryology, time 0 = fertilisation
212
What are the 3 stages of implantation in pregnancy?
Apposition
Attachment
Penetration
213
What is the primitive placenta made up of?
| What does it split into?
Primitive Trophoblast
Cytotrophoblast layer - inner layer of mononuclear cells
Syncytiotrophoblast - outer layer of multinucleated cells
214
What are the 2 components of the placenta once it's fully developed and what are they formed by?
Maternal portion - decidual plate
| Fetal portion - chorion frondosum
215
What are the 3 stages of embryo growth + fetal patterns?
Stage I - hyperplasia
Stage II - hyperplasia + hypertrophy
Stage III - hypertrophy
216
When does most fetal weight gain occur?
95% of fetal weight gain occurs during 2nd half of pregnancy
217
What measurements of the fetus are taken during the ultrasound in the second trimester to asses fetal growth?
```
Head Circumference (HC)
Bi-Parietal Diameter (BPD)
Abdominal Circumference (AC)
Femur Length (FL)
Combine to estimate fetal weight (EFW)
```
218
When is antenatal screening for sickle cell and thalassaemia offered and how is it carried out?
Preconception - 10 weeks
| Blood test
219
When is antenatal screening for infectious disease offered and how is it carried out?
(examples of disease?)
At booking
Serology
HIV, Herpes, Syphilis
220
How is screening performed for chromosome abnormalities?
Combined test:
Fetal nuchal translucency
Maternal serum βHCG
Maternal serum PAPP_A
221
When is antenatal screening for fetal anomalies offered and how is it carried out?
Between 18-22 weeks
| Ultrasound
222
What is the definition of maternal death?
Death during/up to 6 weeks after end of pregnancy
| ‘Late’ maternal death covers period from 6 weeks postpartum until 12 months after end of pregnancy
223
What are the 4 categories that cause maternal death?
Direct: due to pregnancy-induced condition
Indirect: due to condition X caused by pregnancy but may have exacerbated it
Unspecified
Incidental: due to external forces
224
Definition of maternal near miss
A woman who nearly died but survived a complication that occurred during pregnancy, childbirth/within 42 days of termination of pregnancy
225
Does peak respiratory flow rate change during pregnancy?
No, if it does could be linked to asthma
226
How much folic acid should a woman take if they're planning a pregnancy?
How many months prior to conception should they start taking it?
How much should be taken if the woman has a higher risk of neural tube defects?
400mcg
3 months
5 mg
227
What is:
a) Meiotic error?
b) Mitotic error?
a) Abnormal gametes arise
b) Germline - gonadal mosaicism
Embryo - mosaic embryo
228
What are the common chromosomes that fuse during robertsonian translocations?
13:14 - 75%
| then 14:21 - 10%
229
What pregnancy risk do female carriers of 14:21 have? (In Robertsonian translocation)
15% risk of trisomy 21 pregnancy
230
What is QF-PCR in prenatal screening?
Quantitative Fluorescent PCR
| Microsatellite markers used to identify + count chromos 13, 18, 21, X/Y
231
How is array CGH analysis carried out?
Compares 2 complete genomes
| Detects differences in copy no across entire genome
232
What is measured in the combined test for Down's syndrome?
Maternal age
Measurement of nuchal translucency (12 week scan)
Gestational age from length of fetus (CRL length)
Level of PAPP-A + free B-hCG in maternal blood
233
How are the hormone levels affected in Down syndrome?
PAPP-A commonly decreased in T13, 18 + 21
Free β-hCG commonly increased in T21 + decreased
in T13 + 18
234
What is measured in the quadruple test for Down's syndrome?
Alpha-fetoprotein (AFP)
Human chorionic gonadotropin (hCG)
Unconjugated estriol (uE3)
Inhibin A
235
What happens during the 1st stages of labour?
Days: Contractions develop + cervix softens
Hours :Regular contractions - 3 erry 10 min), dilation of cervix (3-4cm -10cm)
Oxytocin can be given to help
236
What happens during the 2nd stage of labour?
Cervix fully dilated - 10 cm
| Strong propulsive contractions - 1-2 hours
237
What is the puerperium stage of pregnancy?
Time from end of 3rd stage through 1st few weeks after delivery, as woman’s body returns to non-pregnant state (usu 6-8 weeks)
AKA postnatal/postpartum
238
What are the prenatal effects on brain formation in weeks 3-4? (what defects occur?)
Affects induction dorsally
Myelomeningocele (spina bifida)
Genetic/nutritional
Motor + perceptual defects
239
What are the prenatal effects on brain formation in weeks 5-6? (what defects occur?)
Affects induction ventrally
Holoprosencephaly - failure form 2 hemispheres
Oft genetic origin
Usu incompatible with life
240
What are the prenatal effects on brain formation in months 2-5? (what defects occur?)
Affects proliferation
Microcephaly - early cessation cell division => abnormally small head
Genetic/trauma factors e.g. infection, fetal alcohol syndrome
Low intellectual abilities
241
What are the 4 developmental domains of childhood development?
Gross motor
Fine motor + vision
Hearing + language
Social + emotional
242
What are the 5 stages of language development?
```
Preverbal communication
Phonological development
Semantic development
Syntax + grammar development
Pragmatics development
```
243
What are the 4 key concepts of developing cognitive skills?
Scheme - internal cognitive structure, provides procedure to use in specific circumstances
Assimilation - process of using scheme to make sense of event/experience
Accommodation - changing scheme cos of new info
Equilibration - process of balancing assimilation + accommodation to create schemes that fit environ
244
What is the 1st main stage of developing cognitive skills?
Sensorimotor, 0-2 yrs
Initial reflexes via sensory motor schema.
Child interacts with environ + manipulates objects
Understanding of object permanence
245
What is the 2nd main stage of developing cognitive skills?
Preoperational, 2-6/7 yrs
Internal representation of concrete objects + situations
Child uses symbolic schemes like language
Ego-centric
Reasoning dominated by perception
246
What is the 3rd main stage of developing cognitive skills?
Concrete operations, 6/7 – 11/12 yrs
Reasoning involves >1 salient feature (conservation)
Logical reasoning only be applied to objects real/can be seen
247
What is the 4th main stage of developing cognitive skills?
Formal operations, 11/12 yrs +
Think logically about potential events/abstract ideas
Test hypotheses about hypothetical events
248
Definition of epigenetics?
Chem modifications to DNA + DNA-associated structures BUT X change DNA sequence
Can regulate gene expression + be inherited across mitotic cell division
249
How does DNA methylation occur?
Addition of Ch3 group onto 5th carbon
5 methylcytosine (5mC)
Methyltransferase enzyme
250
Definition of gonadarche?
Activation of gonads by pituitary hormones FSH-LH
251
Definition of adrenarche?
Increase production of androgens by adrenal cortex
252
Definition of thelarche?
Appearance of breast tissue, cause oestradiol (ovaries)
253
Definition of menarche?
1st menstrual bleed
Oestradiol on endometrial lining
Non ovulatory
254
Definition of spermarche?
1st sperm production
Nocturnal sperm emissions
FSH, LH ==> testosterone
255
Definition of pubarche?
Appearance of pubic hair ==> Androgens from adrenal gland
| 1st appearance of axillary hair, apocrine body odour + acne
256
What hormone starts puberty?
Surge in GnRH
257
What are some features of true central precocious puberty?
```
Gonadotropin dependent
Early maturation of the HPG axis
Sequential maturation
Pathologic 40-75% of boys
Pathologic in 10-20% of girls
Sexual characteristics appropriate for child’s gender
```
258
What is the sequential order of puberty for girls?
Adrenarche, Gonadarche, Breast development (thelarche), Growth spurt, Auxiliary + Pubic hair (pubarche), Menarche
259
What is the sequential order of puberty for boys?
Adrenarche, Testicular enlargement (gonadarche), Auxiliary + Pubic hair (pubarche), Growth spurt, Facial hair, (androgenic hair growth) Voice deepening
260
What hormone does prolactin inhibit?
GnRH
261
Both acromegaly and hypothyroidism have symptoms of weight gain. How would you distinguish between them?
Acromegaly - facial features, unable to fit into clothes at all
Hypothyroidism - trunkal obesity e.g. can't fit into jeans
262
What is the function of aldosterone?
Acts principal cells of kidneys to reduce K+ + increase Na+
Acts ATP pumps of nephrons to absorb bicarb - increases pH
Release controlled by RAAS
263
What is the function of cortisol?
Promotes gluconeogenesis
Increase glc
Released in response stress, low BG (blood glc)
264
In the development of the embryo, what is the name of the structure where the first cell differentiation takes place?
When does this occur?
Morula
| 4 days
265
On weight and height charts for babies, why is there not a measurement recorded in 0-2 weeks?
Natural weight loss as baby energy expenditure increases as it gets used to life outside the womb
Singular measurement doesn't tell you if baby gaining lost weight or actually growing
266
What measurements on a growth chart prompts an investigation?
Measurements that drop off 2/more centiles
| Single measurements below 0.4 centile/above 99th centile
