Brainscape's Knowledge GenomeTM

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


See full index

Physiology II Exam III > Energy And Metabolism II > Flashcards

Energy And Metabolism II Flashcards

1
Q

Characteristics of phosphocreatine.

A
  • has a high energy phosphate bond
  • is 3-8x more abundant than ATP
  • cannot participate directly in energy transfer
  • can transfer energy interchangeably with ATP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why are essential aa considered essential?

A

-cannot be synthesized in the body or are not synthesized easily or in large quantities

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

What does non-essential aa formation depend on?

A

-alpha keto acid precursors

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

Review synthesis of alanine from pyruvic acid

A

:)

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

What is considered the most intracellular process that requires energy? How much energy is required?

A
  • formation of peptide linkages

- 500-5000 calories per mole

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

Outline how peptide bonds are made.

A
  • aa + ATP -> aa-AMP + 2P
  • aa-AMP + tRNA -> aa-tRNA +AMP
  • attachment of tRNA to mRNA via codon-anticodon pairing
  • formation of peptide bond with second aa using peptidyl transferase + GTP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How many phosphate bonds are needed to form one peptide linkage?

A

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens to excess aa in the body?

A

-degraded and used for energy

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

Outline the steps of protein degradation.

A
  • deamination (involves transamination and end product is ammonia)
  • two molecules + one molecule of CO2 are combined in the liver to form urea
  • this occurs in the urea/ornithine cycle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Who discovered the ornithine/urea cycle?

A

Kreb’s 5 years before he discovered the TCA cycle

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

Where does the ornithine cycle take place?

A

-mitochondria and cytoplasm

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

Outline the steps that take place in the mitochondria. ornithine cycle

A
  • ammonia +CO2 -> carbamoyl phosphate

- carbamoyl phosphate + ornithine -> citrulline

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

Outline the steps that take place in the cytoplasm. (Ornithine cycle)

A
  • citrulline + Asp -> argininosuccinate
  • argininosuccinate -> Arg + fumarate
  • Arg -> urea + ornithine
  • fumarate can enter the TCA cycle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Rate of overall chemical reaction is determined by what?

A
  • [enzyme]

- [substrate]

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

What happens when substrate concentration is high?

A
  • rxn rate is determined almost entirely by conc of enzyme

- ex. Diabetes mellitus and glucose

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

What happens when the enzyme concentration is high?

A
  • rxn rate becomes directly proportional to conc of substrate and enzyme
  • ex. Absorption of substances from intestinal tract and renal tubules when concs of the substrate are low compared to transport enzymes
17
Q

Most chemical reactions in the body occur in series, what is the overall rate of rxn determined by?

A

-slowest step in the series
+rate limiting step
+ADP is the major rate limiting factor for almost all energy metabolism in the body

18
Q

About ______ of energy in foods becomes heat during ATP formation.

A

35%

-more heat is produced in the transfer of energy from ATP to the functional systems of cells

19
Q

No more than _____ of energy from food is used by the functional systems. What is most of this converted to?

A

27%

-converted into heat, exception is energy transferred outside the body as potential energy (eventually will turn into heat)

20
Q

What are some factors that influence metabolic rate?

A
  • arousal vs sleeping
  • skeletal muscle
  • age
  • thyroid activity
  • testosterone
  • growth hormone
  • fever
  • sleep
  • malnutrition
21
Q

____ of energy expended by body is derived from oxidative phosphorylation involving differnt kinds of food.

A

95%

22
Q

What can whole body metabolic rate be calculated from?

A

-rate of oxygen utilization

-metabolize 1 liter of oxygen with:
+glucose: 5.01 Cal
+fat: 4.7 Cal
+protein: 4.6 Cal

23
Q

Energy liberate per liter of oxygen with average diet averages about 4.825 Cal

A

Energy equivalent of oxygen

24
Q

BMR normally averages _______ Cal per hour

A

65-70

25
Q

How does thyroxine affect BMR?

A
  • thyroxine increases rate of chemical reactions in cells and increases metabolic rate
  • maximal secretion may increase metabolic rate 50-100% above normal
  • loss of thyroid secretion decreases metabolic rate to 40-60% of normal
26
Q

How does testosterone affect BMR?

A
  • testosterone can increase metabolic rate 10-15%

- mainly related to anabolic effect of increase in skeletal muscle mass

27
Q

How does malnutrition affect BMR?

A
  • malnutrition results in reduced food substances in the cells
  • this results in a marked reduction in metabolic rate
  • this process may accompany final stages of many disease conditions
28
Q

What, on average, are there components of energy expenditure? What activities?

A
  • BMR (60% daily energy usage)
  • thermic effect of food (8%)
  • no exercise activity (7%)
  • purposeful physical activity (25%)
29
Q

Skeletal muscle accounts for ____ to _____ percent of BMR even at rest, BMR is typically corrected for differences in body size.

A

20-30%

30
Q

What accounts for increasing decline in BMR with increasing age?

A

-related to loss of muscle mass and replacement with adipose tissue with a lower rate of metabolism

31
Q

Phosphocreatine functions as what?

A

-an accessory storage depot for energy and as an ATP buffer

Physiology II Exam III (9 decks)

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