Met 1 - Energy production Flashcards Preview

ESA1 > Met 1 - Energy production > Flashcards

Flashcards in Met 1 - Energy production Deck (99)
1

Define Catabolism:

The breakdown of molecules to release energy

2

Breakdown of molecules via oxidation produces:

ATP
CO2
H20
Heat

3

Define Anabolism:

Uses energy and raw materials to make larger molecules for growth and maintenance

4

How many kJ are released per gram of carbohydrate?

~ 17 kJ/g

5

Name the 5 dietary carbohydrates:

1) Starch
2) Glucose
3) Fructose
4) Lactose
5) Sucrose

6

What is the normal range of fasting blood glucose in mM?

~ 3.3-6 mM

7

What are the 7 essential components of our diet?

1) Carbohydrate
2) Protein
3) Fat
4) Water
5) Fiber
6) Vitamins
7) Minerals

8

Approx. how many grams of protein should we consume per day?

~ 35 g/day

9

Name the 9 essential amino acids:

1) Isoleucine
2) Leucine
3) Threonine
4) Histidine
5) Lysine
6) Methionine
7) Phenylalanine
8) Tryptophan
9) Valine

10

How many amino acids are 'essential'?

9

11

Name a 'complete protein', which contains all the essential amino acids:

- Meat
- Fish
- Eggs
- Dairy (Milk/yoghurt/whey)
- Quinoa
- Buckwheat
- Hemp seeds
- Chia seeds
- Spirulina

12

How many of the 22 amino acids required, can be synthesised by the body?

13 amino acids

13

Which vitamins are fat soluble?

Vitamins A, D, E and K

14

How many kJ are released per gram of protein?

~ 17 kJ/g

15

How many kJ are released per gram of fat?

~ 37 kJ/g

16

Name the 2 essential fatty acids:

1) alpha-Linoleic acid
2) Linolenic acid

17

Which 2 vitamins have antioxidant roles?

1) Vitamin C
2) Vitamin E

18

Which vitamins require fats to be absorbed?

Vitamins A, D, E and K

19

What percentage of an Adults body weight is water?

~ 50-60 %

20

What is the average water loss from your body per day?

~ 2.5 L/day

21

How is water lost from the body?

- Urine
- Faeces
- Sweat
- Expelled air

22

How many grams of fiber should be ingested per day?

~ 18 g/day

23

Approx. how many liters of water should be ingested per day?

~ 2-3 L

24

Why is cellulose non-digestable (fibre)?

Humans do not possess an enzyme to break the beta-1,4-glycosidic bonds

25

How does fibre increase metabolism of food in the GI tract?

It increases the SA of the gut to which substrates can bind, increasing the chance of enzymes finding them = food digested quicker.

26

A low fiber diet is a risk factor for which type of cancer?

Colorectal cancer

27

Daily Energy Expenditure is the sum of :

1- Basal Metabolic Rate
2- Diet-Induced Thermogenesis
3- Physical activity level

28

What is 'diet-induced thermogenesis'?

The energy required to digest food (~10% of energy content of ingested food)

29

What is the recommended intake of a 70kg man doing moderate exercise per day in kJ?

~ 12,000 kJ/day

30

What is the recommended intake of a 58 kg woman doing moderate exercise per day in kJ?

~ 9,500 kJ/day

31

How is Basal Metabolic Rate calculated?

weight in kg x 100 = kJ/day

32

Why is a woman's BMR less than a man?

Women have more adipose tissue than men, which is less metabolically active, so less energy expended.

33

What is the average BMR of a 70kg man in kJ/day?

~ 7000 kJ/day

34

What is the avergae BMR of a 58kg woman in kJ/day?

~ 5800 kJ/day

35

How is BMI calculated?

(weight in kg) / (height in m)^2 = kg/m^2

36

What is the range of a healthy BMI?

18.5 - 24.9 kg/m^2

37

A man is classified as overweight. What range must his BMI lie within?

25 - 29.9 kg/m^2

38

A woman is classified as obese. What range must her BMI lie within?

30 - 34.9 kg/m^2

39

Severely obese is a BMI over what value?

35 kg/m^2

40

Why is total starvation not a preferred method of weight loss?

Total starvation increases protein metabolism, decreasing amount of lean tissue, and causes fats to be broken down into ketone bodies which disrupts pH

41

What is the main disadvantage of using BMI to estimate health?

BMI may wrongly classify a muscular individual as overweight/obese

42

What ratio can be used as an alternative to BMI?

Waist/Hip ratio

43

Which body shape has a higher risk of disease and death: apple or pear?

Apple: Fat distribution on torso carries a higher risk.

44

What name describes protein-energy malnutrition?

Marasmus

45

What is the classic presentation of someone suffering from marasmus?

Child

46

What name describes protein malnutrition?

Kwashiorkor

47

What is the classic presentation of Kwashiorkor?

Child
Thin discoloured hair
Ascites (distended abdomen)
Pitting oedema
Anaemia
Large fatty liver
Skin discolouration
Anorexia
Irritability

48

Why is kwashiorkor common in children after they have been weaned off breast milk? (in underdeveloped countries)

Breast milk contains protein and essential amino acids, keeping the child healthy.
Breast milk is then often replaced with diet high in carbohydrates, but protein deficient.

49

What causes the large fatty liver seen in patients with Kwashiorkor?

Protein deficiency:
- Apolipoproteins cannot be synthesised
- vLDLs cannot be synthesised
- Lipid synthesised by liver cannot be exported to adipose

50

What 4 forces contribute to Starling's Law of the Capillary?

1) Hydrostatic pressure of the capillary
2) Hydrostatic pressure of the tissue fluid
3) Plasma oncotic pressure
4) Interstitial oncotic pressure

51

Define homeostasis:

The maintenance of a stable internal environment, via a dynamic equilibrium

52

Which groups of people does the EatWell plate NOT apply to?

- Children under 2yrs
- Undernourished
- Overnourished

53

According to the EatWell plate, what percentage of our intake should be:
- Bread/Rice/Pasta
- Fruit/Vegetables
- Dairy
- Meat/Fish/Eggs/Beans
- High in fat/sugar foods

Bread/Rice/Pasta = ~ 33%
Fruit/Vegetables = ~ 33%
Dairy = ~ 15%
Meat/Fish/Eggs/Beans = ~ 12%
High in fat/sugar foods = ~ 8%

54

Which is the only cell type which doesn't synthesis cell components?

Red Blood Cells

55

Which tissue types allow storage of nutrients?

Liver
Skeletal muscle
Adipose tissue

56

Which tissue types allow the interconversion of nutrients?

Liver
Adipose tissue
Kidney cortex

57

Is Catabolism oxidative or reductive?

Oxidative (releases H+)

58

Is Anabolism oxidative or reductive?

Reductive (Uses H+)

59

Name the 5 types of cell work which requires energy:

- Mechanical work
- Biosynthetic work
- Transport work
- Electrical work
- Osmotic work

60

Approx. how long can the body survive with only water intake?

~ 20-70 days, depends on energy stores

61

Via which mechanism is ATP synthesised DIRECTLY?

Substrate-level phosphorylation

62

Via which mechanism is ATP synthesised INDIRECTLY?

Oxidative phosphorylation

63

How much energy (in kJ/mol) is released when ATP ---> ADP + Pi?

~ 37 kJ/mol

64

Why is ATP a carrier of energy, not a store?

Due to limited amount of ATP and ADP in a cell, they must be constantly recycled

65

Which reaction does Creatine Kinase catalyse?

Creatine + ATP ---> Creatine Phosphate + ADP

66

What molecule is used as a store of energy in cardiac/skeletal muscle, which provides instant energy for sprinting?

Creatine Phosphate

67

How much energy is released from 1 mole of Creatine Phosphate? (kJ/mol)

~ 43 kJ/mol

68

How much energy is released from 1 mole of Phosphoenolpyruvate (+ ADP ---> Pyruvate + ATP)

~ 62 kJ/mol

69

How much energy is released from 1,3-Bisphosphoglycerate (+ADP ---> 3-Phosphoglycerate + ATP)

~ 49 kJ/mol

70

Name the main 4 high energy molecules containing phosphate groups:

1) ATP
2) Creatine phosphate
3) 1,3-Bisphosphoglycerate
4) Phosphoenolpyruvate

71

What marker is used as an indicator of skeletal muscle wasting and/or kidney function?

Creatinine

72

Skeletal muscle wasting would increase excretion of Creatinine. Why?

Skeletal muscle contain Creatine and Creatine Phosphate, which are released when these cells die. They can both form Creatinine non-enzymatically = increased excretion.

73

Working at 95% effort for 10 secs would cause skeletal muscle cells to use what substrates for energy?

- ATP
- Creatine kinase

74

Working at 95% effort for 10 mins would cause skeletal muscle cells to use what substrates for energy?

- Muscle glycogen
- Fatty acids

75

What is the general formula of carbohydrates?

(CH2O)n

76

Why are carbohydrates hydrophilic?

Contain multiple -OH groups (attract H2O)

77

What word is used to describe a single sugar unit?

Monosaccharide

78

How many C atoms does a monosaccharide contain?

~ 3-9 C atoms

79

What is the naturally occurring form of monosaccharides?

D-form

80

What can't carbohydrates passively cross a cell membrane?

Water-soluble (hydrophilic)

81

Why do carbohydrates require less O2 for complete oxidation compared to fatty acids?

Carbohydrates are already partially oxidised

82

What is a disaccharide?

2 sugar units connected via a glycosidic bond

83

What sugar units form Maltose?

2 x Glucose units

84

What sugar units for Galactose?

Glucose + Galactose

85

What sugar units form Fructose?

Glucose + Sucrose

86

Name the highly branched polymer of glucose mainly found in mammals:

Glycogen

87

In which tissues is Glycogen (mainly) stored?

Skeletal muscle
Liver

88

Which bonds does Glycogen contain?

alpha-1,4 -glycosidic
alpha-1,6 -glycosidic

89

Which polymers of Glucose are mainly found in plants?

1) Cellulose
2) Starch

90

When Starch is hydrolysed in the GI tract, what molecules are released?

Glucose + Maltose

91

Which bonds does Starch contain?

alpha-1,4 -glycosidic
alpha-1,6 -glycosidic

92

When Glycogen is hydrolysed in the GI tract, what molecule(s) are released?

Glucose

93

Which bonds does Cellulose contain?

beta-1,4-glycosidic

94

Which polysaccharide is not digestable by humans?

Cellulose

95

Which enzymes are required for the hydrolysis of dietary polysaccharides?

Glycosidase enzymes ie:
- Salivary amylase
- Pancreatic amylase

96

Which bonds are cleaved by Amylase enzymes?

alpha-1,4-glycosidic bonds

97

Where in the GI tract are the enzymes which hydrolyse dietary disaccharides?

Brush border of epithelial cells, lining the Duodenum and Jejunum

98

Which enzymes are required for the hydrolysis of dietary disaccharides?

Glycosidase enzymes ie:
- Lactase
- Glycoamylase
- Sucrase-Isomaltase

99

What transporter is required for Glucose and/or Galactose absorption from the GI lumen into the epithelial cells?

SGLT = Na+-Glucose Cotransporter