Physiology Flashcards
Where in the body is angiotensin I converted to angiotensin II under the influence of angiontensin-converting enzyme?
Lungs
The amniotic fluid volume peaks at around 900ml. At what gestation does the amniotic fluid reach its maximum volume?
35 Weeks
What is the typical time taken for wounds closed by primary intention to reach full tensile strength?
12 Weeks
Where in the kidney is the majority of Bicarbonate reabsorbed??
Proximal Convoluted Tubules
What is the primary form of haemoglobin in a 6 week old foetus?
Hb Gower 1
Placental production of hPL, hCG, Oestrogen and Progesterone are examples of which type of mechanism?
Endocrine
What is the typical volume
increase from a non-pregnant to term
uterus?
10 ml to 5000 ml
What is the typical weight of a non-pregnant premenopausal uterus?
40 gm
Which of the following is a primary site of Prostaglandin E2 (PGE2) production?
Placenta
During pregnancy which hormone(s) inhibit lactogenesis?
Oestrogen and Progesterone
In the 3rd trimester anemia is defined by?
Haemoglobin < 10.5 g/l
GERD is common in pregnancy, esophageal sphincter relaxes due to what hormone?
Progesterone
PR interval in Wolff Parkinson White syndrome
Rapid interval <0.1 sec
Stroke Volume
SV= End diastolic Volume - End sysolic volume
Ejection Fraction
EF= SV/EDV
Location of Carotid Sinus
Bifurcation of common carotids
ACE converts
Angiotensin I to Angiotensin II
The main Stimulus to respiratory centers
Chemoreceptors
The main chemical mediator responsible for the closure of patent ductus arteriosus
Bradykinin (from the lungs)
Administration of Prostaglandin antagonist soon after birth used to therapeutically close what patent structure?
Ductus Arteriosus
During Lactation, “let down” reflex is stimulated by which hormone?
Oxytocin
Role of fetus in initiation of labor?
gives CRH
Before labor starts, which factors stop the uterus from contracting?
Progesterone
Catecholamines
Relaxin
Which type of prostaglandins are involved in the ripening of the cervix?
rapid rise in the activity of COX-2 and other inflammatory cytokines at the onset of
labour, leading some to compare labour to an inflammatory process. Increased COX-2 activity leads to an
increase in prostaglandin synthesis; the amnion and chorion secrete primarily prostaglandin-E2, while the
decidua favours prostaglandin-F2α
Furguson reflex?
Pressure effect on cervix
Which interleukin causes cervical ripening?
IL 8
What is the cause of inc in oxytocin receptors in myometrium in the 3rd trimester?
Estrogen
COP increase in pregnancy
40% increase from 4.5 to 6 l/min.
HR increase in pregnancy
10% from 80 to 90 bpm
Peripheral resistance in pregnancy increased or decreased?
Decreased. (d.t. relaxant effect of progesterone in arterial smooth muscles)
Range of normal fetal heart rate ?
110-160 bpm
In pregnancy, alkaline phosphatase ⬆️ or ⬇️
Increases three times its normal levels because it’s also produced by the placenta
What size is a follicle ready to ovulate
> 20 mm
What size is a resting follicle?
> 0.02 mm
Which testicular cells are located outside the blood/testis barrier?
Leydig cells
What is the average haemoglobin concentration in a newborn at term
17 g/dl
Regarding plasma calcium, what proportion is carried in an ionized form
45%
At what gestation does fetal urine become the major contributor to amniotic fluid volume
> 18 weeks
The required daily intake of which vitamins and minerals is not increased in pregnancy or lactation
VIT D and K
At what gestational age does the formation of the definitive alveoli take place
> 36 weeks
The alveolar stage starts at 36 week and may take up to 2 years postnatal to complete
Which test is used to diagnose haemolytic anaemia in a newborn
Direct Coomb Test
RBCs life span
> 120 days
Platelets life span
> 5 - 10 days
Increase of Oxygen consumption in pregnancy
> 50 ml/min
Mendelson syndrome
known as peptic pneumonia, refers to acute chemical pneumonitis caused by the aspiration of stomach contents in patients under general anesthesia.
Kidneys percent of COP
25% = 1.2L
Renal Plasma Flow normally equals
660 ml/min
Creatinine clearance
120 ml/min
GFR normally equals
120 ml/min (less 10% in females)
Bladder is stimulated at what volume
300 ml
Gestational age of Luteo-placental shift
6 weeks
Start of fetal erythropoesis
6 weeks gestations
Number of primordial follicles at 6 months gestation
5-7 millions
Number of primordial follicles at birth
1-2 million
Number of primordial follicles at puberty
400.000 follicles
What percentage of hemoglobin is HbF in the newborn?
50-90%
Cardiac output is calculated by
Stroke Volume X Heart Rate
What is the average lifespan of a basophil (white blood cell)?
3-4 days
Where in the kidney is the majority of Bicarbonate reabsorbed
Proximal Convoluted tubules
What is the typical volume increase from a non-pregnant to term uterus?
10-5000 ml
Following parturition uterine contractions called After-pains may typically continue for how long?
2 - 3 days
At what gestational age does the luteo-placental shift occur?
6 -8 weeks
During pregnancy which hormone(s) inhibit lactogenesis?
Estrogen and Progesteron
During pregnancy the GFR changes as
GFR increases by 40%
Which structure is the primary mechanism for shunting blood away from the fetal pulmonary circulation?
Foramen Oval
Which test is most appropriate in diagnosing the thyroid dysfunction in pregnancy?
Free thyroxine (T4) levels
Which mechanism of transfer do oxygen and carbon dioxide cross the placenta?
Simple diffusion
Which part of the nephron has receptors for antidiuretic hormone (ADH) (vasopressin)?
Collecting Duct
What structure carries the electrical impulse from the sino-atrial node to the atrio-ventricular node?
Cardiac smooth muscle
What is the blood flow to the uterus in a term pregnancy?
700 ml/min
Minute ventilation in pregnancy increases due to
Increased Progesterone
Which cells are responsible for the production of surfactant?
Type II pneumocytes
What is the percentage change in minute ventilation during the first trimester of pregnancy?
40% increase
Ootidogenesis refers to
1st and 2nd Meiotic Divisions
At what gestational age does the formation of the definitive alveoli take place?
36 weeks
During lactation the ‘let-down’ reflex is stimulated by the action of which hormone?
Oxytocin
Urea is transferred from fetal circulation to maternal circulation via which transport mechanism?
Passive diffusion
Ammonia is transported from fetal to maternal circulation by
Active transport
How many days does it take from the resting follicle stage to ovulation?
375 days
LH peak precedes ovulaQon by?
16 h
Which one of the following best describes the histological type of endometrium
soon after ovulation?
Secretory endometrium
The use of hormone replacement therapy (HRT) will decreases the risk of which cancer?
colorectal cancer
HRT benefits :
• ↓ Vasomotor symptoms.
• ↓ urogenital symptoms and improved sexuality.
• ↓ Risk of osteoporosis .
• ↓ Risk of colorectal cancer.
Wernicke-Korsakoff syndrome Deeiciency disease of vitamin?
Vit. B1
For overactive bladder a new drug called Mirabegron is used. Which is the single mechanism of action for this drug?
Selective Beta-3 antagonist
Primary stimulator of uterine involution after delivery is
Oxytocin
Physiological anemia occurs in what gestational age
32 weeks
WHAT IS THE TOTAL BLOOD VOLUME IN A TERM NEWBORN?
85 ml/kg
Peak maternal hCG concentration at week
10 weeks
Which organisms do type II PNEUMOCYTES utilifor surfactant release
Lamillar bodies
Q34. Antibodies present in a patient of O positive blood group
Anti A,Anti B & Anti-D
How many sperms produced in 24 hours
30 million
What happens to both intrathoracic volume and pressure on inspiration
Volume increases
pressure decreases
What is the motor nerve root supply to the diaphragm
C3,4,5
What metabolite is produced when vitamin D is metabolized by liver
25 Dihydroxycholecalciferol
Which substance gives the most accurate measurement of the glomerular filtration rate
Insulin
During labor what is the minimum intrauterine pressure achieved by contractions to progressively dilate the cervix
25mmhg
What happens to the systolic and diastolic blood pressure in the first trimester
Systolic doesn’t change
diastolic decreases
Which vitamin is the only one that is water soluble
Vit B
At what stage of pregnancy is there an increase in serum alkaline phosphatase concentration
Third trimester
What is the concentration of potassium cations in extracellular and intracellular fluid
ECF: 4 meq/L
ICF: 140 meg/L
At what gestational age does the fetus typically start swallowing
12 weeks
First fetal urine produced at
8 to 11 weeks
Typical O2 consumption in non pregnant women
250 ml/min
In pregnancy increases 50ml to be 300 ml/min
What is the primary form of hemoglobin in a 18 week old fetus
HbF
Before 10-12 weeks: embryonic Hb
After 10-12 weeks: fetal Hb
Aldosterone promotes water retention via which mechanism
Regulation of sodium potassium pumps in distal tubule and collecting ducts
What percentage of hemoglobin is HbF by six months of age
<2%
Upregulation of urea movement through urea transport proteins in the collecting ducts is effect of 
Vasopressin
What is the maximum normal menstrual blood loss
85 ml
Average blood loss= 35-40 ml
What is average volume of blood loss during the Menstrual cycle
35 - 40 ml
Following partiurition how long does involution of the uterus take
4-6 weeks
Mature breast milk composition
Fat 4%
Protein 1%
Sugar 7%
Causes of prolonged prothrombin time (and also INR)
- Factor V deficiency
- Warfarin Therapy
- Liver Failure
- DIC
Primary stimulus of ADH release is
High serum osmolality
mean arterial pressur (MAP) is equal to
DBP + 1/3 (pulse pressure)
Blood flow through cerebral circulation is directly proportion to:
pCO2
By how much does the overall size of the kidney increase during pregnancy ?
1 cm
What is the relative concentration of follicle-stimulating hormone (FSH) and oestradiol in the late menopausal transition?
High FSH level and low oestradiol level
Renal site where aldosterone mainly exerts its action?
Distal convoluted tubules
99% of body calcium is in what form?
Calcium phosphate
During pregnancy what changes of the upper respiratory mucosa would you expect to see?
Increased phagocytic activity and increased mucopolysacchride content
Commonest cause of hypercalcemia in UK, (30 / 100000)
Primary Hypepararthyroidism
The Haldane effect refers to
The increased capacity for deoxygenated blood to carry CO2
The softening of the cervical isthmus that occurs early in gestation is called:
Hegar’s sign
Insensible loss of water from sweat and lungs in 70 years old healthy woman is?
850 ml/kg
T- score to asses bone density
+1 to >-1 Normal
-1 to -2.25 Osteopenia
<-2.25 Osteoprosis (+fractures = severe)
