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Flashcards in Special Circumstances Deck (40)
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1
Q

What proportion of the fetal growth occurs in the last trimester?

A

2/3

2
Q

When is the anabolic phase of pregnancy and why does this happen?

A

early pregnancy

increase nutrient stores in preparation for high demand from foetus

3
Q

When does the catabolic phase of pregnancy occur?

A

late pregnancy

4
Q

Why is there a small increase in insulin sensitivity in early pregnancy?

A

To increase fatty acid uptake so that stores of TAG are increased.

5
Q

Why is insulin sensitivity in the mother decreased in late pregnancy?

A

nutrients are directed to foetus

less glucose is used by the mother

6
Q

How do most substances travel across the placenta?

A

simple diffusion

7
Q

Name a molecule type that requires active transport to cross the placenta

A

amino acids

8
Q

Which transporter is required in the placenta for glucose?

A

GLUT1

9
Q

What is the fetoplacental unit?

A

A new endocrine entity that can control the maternal hypothalmic pituitary axis.

10
Q

Give examples of hypothalamic like hormones secreted by the placenta

A

CRH
GnRH
TRH
GHRH

11
Q

Give examples of pituitary like hormones released from the placenta

A

ACTH
hCG
cCT
hPL

12
Q

Which 2 steroid hormones are released from the placenta?

A

Oestriol and progesterone

13
Q

What does the first half of pregnancy prepare the mother for?

A

rapid growth rate of the foetus
birth
lactation

14
Q

How does maternal utilisation of nutrients change?

A

uses less glucose

utilise more fatty acids

15
Q

What are the anti-insulin hormones that the fetoplacental unit releases?

A

CRH
hPL
progesterone

16
Q

When can maternal hypoglycaemia occur and why?

A

between meals and at night time

due to the continuous fetal draw of glucose

17
Q

How do oestrogens and progesterones affect beta cells?

A

They increase the sensitivity of beta cells to glucose. This results in beta cell hyperplasia and hypertrophy. Therefore more insulin in synthesised and secreted.

18
Q

What happens if the beta cells do not respond normally to pregnancy?

A

The maternal blood glucose increases and the mother may get gestational diabetes.

19
Q

What is overt diabetes?

A

Diabetes that was discovered in pregnancy but was present before.

20
Q

What is gestational diabetes?

A

A disease in which the pancreatic beta cells do not produce sufficient insulin to meet increased requirement in late pregnancy.

21
Q

What are the 3 known causes of gestational diabetes?

A

beta cell dysfunction
autoantibodies
genetic susceptibility

22
Q

What does gestational diabetes increase the incidence of?

A

miscarriage
congenital malformation
fetal macrosomia (large body)
shoulder dystocia (shoulders stuck during birth)
hypertensive disorders eg. gestational hypertension/preeclampsia

23
Q

What defines preeclampsia?

A

High blood pressure and protein in the urine whilst pregnant

24
Q

What are the risk factors for gestational diabetes?

A
age
BMI
more common in Asians, Blacks and Hispanics
family history of diabetes
family history of macrosomia
25
Q

What is the management for gestational diabetes?

A

calorie restriction
insulin injections if severe
regular ultrasounds to check on foetal development

26
Q

What should be ensured in exercise?

A

rate of mobilisation = rate of utilisation
minimal disturbance to homeostasis
glucose supply to brain maintained
end products of metabolism removed quickly

27
Q

How long do the ATP stores in muscle last?

A

approx 2 seconds

28
Q

How long does creatine phosphate last?

A

approx 5 seconds

29
Q

What accounts for the largest amount of ATP usage in exercise?

A

The myosin ATPase that is used for the sliding filament model of contraction.

30
Q

How long could you exercise at low intensity using only the glycogen from the muscle and liver?

A

60 minutes

31
Q

What is the principal organ for the regulation of glucose?

A

The liver because it recycles lactate.

32
Q

Which transporters are used in the muscle for glucose uptake?

A

GLUT4

GLUT1

33
Q

What is the cascade sequence for increased GLUT4 expression?

A

increased glucose in cell
increased AMP
AMPK activated
GLUT4 channels expressed on cell surface

34
Q

How is ATP produced during a 100m sprint?

A

anaerobically because the body cannot deliver sufficient oxygen
lactate builds up
muscle store of glycogen is used

35
Q

How is ATP produced in a medium intensity 1500m race?

A

some oxygen can be delivered so partly aerobic and partly anaerobic
fatty acids can be utilised
muscle glycogen is utilised

36
Q

How is ATP produced during a marathon?

A

95% aerobic

muscle glycogen, liver glycogen and fatty acids are utilised

37
Q

What happens to insulin and glucagon levels during a marathon?

A

insulin levels slowly decrease

glucagon levels increase

38
Q

What hormones, other than glucagon, increase during a marathon?

A

adrenaline
growth hormone
cortisol

39
Q

What are the benefits of exercise?

A
change in body composition
glucose tolerance improves
insulin sensitivity increases
blood triglycerides decrease
blood pressure falls
psychological effects
40
Q

What is the average weight gain of a pregnant women?

A

8kg