Brainscape's Knowledge GenomeTM

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


See full index

Block D - Digestion and Metabolism > Bioenergetics > Flashcards

Bioenergetics Flashcards

1
Q

Define “nutrient”

A

Any dietary element the body is able to use to help meet a biochemical requirement for health

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

Define “esential nutrient”

A

A nutrient that is essential for health

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

2 reasons why a nutrient may be “non-essential”

A
  1. Another nutrient is able to serve the same metabolic function
  2. The body can synthesize this particular nutrient from a different one
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

4 nutrient classes that provide chemical energy

A
  • Lipids
  • Carbohydrates
  • Proteins (amino acids)
  • Ethanol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 levels of organization for the functions that keep you alive

A
  1. Cellular
  2. Whole body
  3. External work
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define the cellular level of organization for the functions that keep you alive (5 points)

A
  • Maitnenance of trans-cellular ionic gradients
  • Transport of substrate molecules
  • Biosynthesis and selective biodegradation
  • Creation, transmission, sensing and response to neural and hormonal signals
  • Whole cell turnover
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Define the whole body level of organization for the functions that keep you alive (7 points)

A
  • Internal work of moving the blood through the circulation
  • Respiration
  • Formation and excretion of urine
  • GI digestive and absorptive functions
  • Body temperature regulation
  • Maintenance of body posture and position
  • Muscular activity not involving external work
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Amount of chemical energy converted to heat per hour by a 70 kg person at rest

A

Approx. 85 kcal/h

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Typical rate of energy flow through the body

A

2500 kcal/day

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

Amount of ATP the body must synthesize and hydrolyze and what this means

A
  • 65 kg of ATP/day –> 45 g/min
  • Body contains only about 45 g of ATP –> complete ATP turnover every minute
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define the Pasteur effect

A

Accelerated glycolysis under anaerobic conditions

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

Why is anaerobic glycolysis must less efficiency than the aerobic pathway?

A

It generates NADH, but WITHOUT oxygen present, it cannot be re-oxidized back to NAD+ –> accumulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define lactic acidosis

A

The buildup of lactic acid in tissues and blood under anaerobic consitions (oxygen debt)

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

How to measure the maximum capacity to do physical work

A

Measure maximum oxygen uptake rate (VO2 max)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where is surfeit carbon stored?

A

Adipose tissue as triglycerides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Define direct calorimetry

A

Measurement of the body’s rate of heat production in order to determine its rate of oxidation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Equation for glucose oxidation

A

6O2 + 6[C-HOH] = 6CO2 + 6H2O + HEAT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Equation for long-chain fatty acid oxidation

A

3/2nO2 + [-(CH2)-]n = nCO2 + nH2O + HEAT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Give the 4 nutrient classes in order of the heat they produce when they are oxidized

A
  • Triglycerides (9kcal/g)
  • Ethanol (7 kcal/g)
  • Carbohydrate (4 kcal/g)
  • Protein (4 kcal/g)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define indirect calorimetry

A

The inference of the rate of fuel oxidation by measuring oxygen consumption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Conversion factor relating oxygen consumption to heat production

A

Heat production (kcal/min) = 4.8 x Oxygen consumption (L/min)

22
Q

Define the law of entropy in the scope of bioenergetics

A

Approximately 5% of energy released when a fuel is oxidized is obliged to be converted to heat (the rest is free energy)

23
Q

Describe the distribution of free energy from oxidized fuel

A
  • One half –> new P bonds in ATP (and other high-energy substrates)
  • One half –> Wasted as heat in the metabolic steps leading to ATP synthesis
24
Q

3 major determinants of energy flow

A
  • Basal metabolic rate (BMR) or resitng energy expenditure (REE)
  • Thermic effect of food
  • Energy expended for activities above basal
25
Q

Define BMR or REE

A

The rate of fuel oxidation while a person is quietly lying at rest and simply “staying alive”

The rate of heat production of a person who is physically and mentally comfortable, relaxed, and reclininc in a thermo-neutral environment several hours after the previous meal

26
Q

Define the thermic effect of food

A

The small amount of heat released to deal with the food consumed in meals

27
Q

4 situations where metabolic stress can occur

A
  • Tissue samage
  • Inflammation
  • Severe infection
  • Certain metabolic diseases
28
Q

Define metabolic stress

A

Increase in the body’s metabolic traffic, use of ATP and heat production

29
Q

Define fever

A

Increase in the body’s core temperature from above its normal set point of 37 degrees C

30
Q

3 ways the body achieve a higher set point temperature

A
  • By ozidizing fuel faster to generate more heat
  • By inducing shivering
  • By sending a message to the conscious brain that makes it feel uncomfortable cold –> put on sweater and blankets
31
Q

Proportion of total daily expenditure by REE in sedentary individuals

A

2/3

32
Q

Rule of thumb to predict a person’s REE

A

For a non-obese adult:

  • REE = 1.0 kcal/kg body weight/hour (man)
  • REE = 0.95 kcal/kg body weight/hour (woman)
33
Q

Compare the REE of an obese person to an average person

A

Higher than “normal” (i.e. the REE they would have or will have after they eliminate their excess fat and achieve a normal body composition)

34
Q

Proportion of the total energy in the food consumed that is occupied by the thermic effect of food

A

8%

35
Q

2 categories of physical activity

A
  • Deliberate formal professional or recreational exercise
  • Non-exercise activity thermogenesis (NEAT)
36
Q

Define NEAT

A

The changes in posture and movement that occur in the course of the normal routines of daily life

37
Q

Define METS

A

A quantification of the energy expenditure associated with different physical acitivities. One MET = a particular individual’s REE (higher = more effort)

38
Q

Rule for the total daily energy expenditure of a normal sedentary person

A

1.5 x REE

39
Q

Reason for body weight fluctuations throughout the day

A

Increases or decreases in ECF volume associated with changes in:

  • Fluid (and salt) intake
  • Urinary excretion
  • Sweating
  • Evaporation
40
Q

Reason for large, sustained changes in body weight

A

A change in BCM and adipose tissue mass

41
Q

4 classic vital signs

A
  • Body temperature
  • Blood pressure
  • Heart rate
  • Respiratory rate
42
Q

Define temperature

A

The measure of kinetic energy of the molecules in a substance

43
Q

2 factors to determine the amount of heat required to raise the temperature of an object

A
  1. The object’s mass
  2. The amount of energy needed to overcome the intermolecular forces that restrain the vibrations of its molecules
44
Q

What does an elevated body temperature imply?

A

The body is generating heat (and transferring it out of the body) faster than normal

45
Q

2 determinants of the specific rate of fuel oxidation associated with a specific body temperature

A
  1. The rate heat is produced (i.e. rate of fuel oxidation)
  2. The rate heat is dissipating from the body
46
Q

4 factors determining the rate of heat dissipation from the body

A
  • The patient’s surface areas
  • Thermal insulation (skin, subcutaneous fat, clothing, blankets)
  • Ambient room temperature and humidity
  • Capacity to perspire
47
Q

A direct regulator of REE

A

Thyroxin

48
Q

Effect of anticholinergic drugs on perspiration and the significance of this fact

A

Inhibition of perspiration –> characteristic clinical sign of poisoning = fever

49
Q

Explain why fever occurs in toxic doses of aspirin

A

Uncoupling of oxidative phosphorylation –> release free energy of ATP as heat

50
Q

Approximate rule for predicting a patient’s metabolic rate

A

Under constant conditions of heat dissipation, each 1 degree C increase in body temperature implies an increase in the rate of fuel oxidation by a factor of 1.1

Block D - Digestion and Metabolism (29 decks)

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