Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

ESA1 - Metabolism > Control Of Metabolism - Pregnancy And Exercise > Flashcards

Control Of Metabolism - Pregnancy And Exercise Flashcards

1
Q

How are nutrients transported from the maternal to fetal blood?

A
  • ACROSS PLACENTA
  • Most substances DIFFUSE DOWN A CONCENTRATION GRADIENT
  • Glucose is transported across GLUT1 receptor
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the principal fuel for fetal growth?

A

Glucose

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

What is meant by the ‘fetoplacental unit’?

A

Placenta, fetal adrenal glands and fetal liver form a NEW ENDROCRINE ENTITY

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

Name 2 steroid hormones produced by the placenta

A
  • Progesterone

- Oestriol

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

How do insulin levels change in the first half of pregnancy?

A
  • Increased insulin secretion to promote ANABOLIC processes

- Increased LIPOGENESIS helps with building maternal nutrient stores

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why must maternal nutrient stores be built up during the first half of pregnancy?

A

Nutrients in preparation for:

  • Rapid growth of fetus
  • Birth
  • Subsequent lactaction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why does increased lipolysis occur during the second half of pregnancy?

A
  • Breakdown of maternal fat stores from first half of pregnancy
  • REDUCES MATERNAL GLUCOSE UTILISATION by metabolism of fatty acids rather than glucose
  • Glucose is spared for rapid growth of fetus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain how the insulin/anti-insulin ratio falls during the second half of pregnancy

A
  • Fetoplacental unit secretes anti-insulin hormones into maternal blood AT A FASTER RATE than maternal insulin secretion
  • Overall anti-insulin concentration is greater than insulin concentration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the main anti insulin hormone secreted by the placenta?

A

Corticotropin releasing hormone CRH

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

What is the effect of anti insulin hormones on maternal blood glucose?

A
  • IMPAIRED GLUCOSE UPTAKE

- Transient HYPERGLYCAEMIA due to increased insulin resistance

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

Why does hypoglycaemia occur during meals and fasting in the second half of pregnancy?

A

Continuous draw of glucose to fetus from maternal blood

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

How does insulin secretion during pregnancy affect maternal pancreatic β cells?

A
  • INCREASED APPETITE leads to increased consumption of glucose
  • Oestrogen and progesterone increase sensitivity of pancreatic β cells to glucose
  • Causes HYPERTROPHY and HYPERPLASIA of β cells which leads to increased insulin secretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is gestational diabetes?

A

Pancreatic β cells do not produce sufficient insulin to meet requirements in late pregnancy

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

What are the causes of gestational diabetes?

A
  • β CELL DYSFUNCTION due to obesity and chronic INSULIN RESISTANCE
  • Destruction of β cells by AUTOANTIBODIES
  • Genetic predisposition
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the clinical complications associated with gestational diabetes?

A
  • Increased risk of miscarriage
  • Increased risk of congential malformation
  • FETAL MACROSOMIA
  • Hypertensive disorders such as GESTATIONAL HYPERTENSION and PREECLAMPSIA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is preeclampsia?

A

High blood pressure during pregnancy leads to INCREASED LOSS OF PROTEIN IN URINE

17
Q

How is gestational diabetes managed?

A
  • DIETARY MODIFICATIONS
  • Insulin injections
  • Regular ultrasound scans to assess fetal growth
18
Q

What does the rate of metabolism during exercise depend on?

A
  • Type of exercise
  • Intensity
  • Duration
  • Physical and nutritional state of individual
19
Q

Why must ATP be rapidly resynthesised during a sprint?

A
  • Only enough ATP in muscles to last ~2secs

- NEED TO MATCH RESYNTHESIS RATE WITH HYDROLYSIS RATE to meet metabolic demands

20
Q

Where does the ATP for replenishing muscle stores during exercise come from?

A
  • CREATINE PHOSPHATE
  • Glycolysis
  • Oxidative phosphorylation
21
Q

Describe how muscle glycogen is metabolised during high and low intensity exercise

A

High intensity (no O2):

  • Sustained breakdown of muscle glycogen by MUSCLE GLYCOGEN PHOSPHORYLASE which is activated by adrenaline and AMP
  • Produces glucose-6-P which can enter glycolysis to produce ATP

Low intensity (some O2):

  • Complete oxidation of glucose and glycogen stores from liver and muscle
  • Produce more ATP through oxidative phosphorylation so can last longer
22
Q

Explain how the liver recycles lactate that is produced by muscle cells during exercise

A
  • CORI CYCLE
  • Lactate produced by muscle cells from glucose is transported to liver
  • Liver converts Lactate to pyruvate (via lactate dehydrogenase) which then enters gluconeogenesis to produce glucose
  • Glucose is transported back to muscle
23
Q

Which glucose transporters are present in muscle cells?

A

GLUT1 and GLUT4

24
Q

Why is it essential that blood glucose levels are maintained during exercise?

A

Some tissues have an absolute requirement for glucose e.g. BRAIN, RBC, cornea and lens of eye

25
Q

Why is the use of fat stores limited during exercise?

A
  • REQUIRES OXYGEN
  • Slow release from adipose tissue
  • Limited carrying capacity in blood
  • Limited uptake across mitochondrial membrane
26
Q

Explain how hormone concentrations change during a marathon

A
  • INSULIN levels fall slowly
  • GLUCAGON levels rise (stimulates catabolism of carbs and fat stores)
  • ADRENALINE and GH rise rapidly (stimulates glycogenolysis, lipolysis and mobilisation of fatty acids)
  • CORTISOL rises slowly (stimulates gluconeogenesis and lipolysis)
27
Q

What are the benefits of exercise?

A
  • DECREASES ADIPOSE and increases muscle
  • Improves GLUCOSE TOLERANCE
  • Improves INSULIN SENSITIVITY of tissues
  • Decreases TAGs in blood and stores
  • Decreases BLOOD PRESSURE
  • Psychological effects
28
Q

Explain the metabolic changes that occur during a 100m sprint

A
  • 0-5secs MUSCLE ATP STORES AND CREATINE PHOSPHATE STORES ARE USED UP
  • 5+secs PRODUCE ATP ANAEROBICALLY
  • Production of LACTATE
  • Breakdown of MUSCLE GLYCOGEN stores via gluconeogenesis to MAINTAIN GLUCOSE FOR BRAIN
29
Q

Explain the metabolic changes that occur during a 1500m race

A
  • Initially use CREATINE PHOSPHATE and ANAEROBIC GLYCOGEN METABOLISM
  • Middle phase AEROBIC PRODUCTION OF ATP from MUSCLE GLYCOGEN
  • Final sprint is ANAEROBIC metabolism of glycogen and produces LACTATE
30
Q

Explain the metabolic changes that occur during a marathon

A
  • 95% AEROBIC
  • 0-5mins uses MUSCLE GLYCOGEN STORES
  • 5-60mins uses LIVER GLYCOGEN STORES
  • Utilisation of FATTY ACIDS after 30mins
31
Q

Describe the metabolic changes that occur during pregnancy

A
  • Early pregnancy metabolism of mother is ANABOLIC
  • Nutrients are stored to meet future demands of rapid fetal growth, gestation and lactation after birth
  • Late pregnancy metabolism is CATABOLIC
  • Decreased insulin sensitivity so blood glucose increases and lipolysis of TAGs meaning there is more available for fetal growth

ESA1 - Metabolism (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions