| Question |
Answer |
| Why do we need food? |
Generate energy, aquire fuel substrates for energy reserves and provide raw materials for cell & tissue turnover and for heat loss |
| Body energy = |
energy intake - energy output |
| Why do we need fuel? |
maintain daily activities |
| Why do we need fuel reserves? |
function between meals |
| Why do we need raw materials? |
renew cells and tissues |
| What behavioral mechanisms govern when and how much food we eat? |
hunger and satiety - governed by hormones |
| What is positive balance? |
eating more food than using - gain weight |
| What is negative balance? |
eating less food than we use - lose weight |
| What are the two ways to make ATP? |
glycolysis and oxidative phosphorylation |
| How much ATP is made through glycolysis? |
2 mol ATP + 2 pyruvate per glucose |
| How much ATP is made through oxidative phosphorylation? |
34 mol ATP + CO2 + H20 per glucose |
| What is required for oxidative phosphorylation? |
oxygen - only works under aerobic conditions |
| How is excess fuel from the diet stored? |
glycogen, fat and protein |
| Which fuel storage contains the highest amount of energy stored? |
fat |
| What is the most labile storage form? |
glycogen |
| How much glucose per day is needed to maintain body at rest? |
240g glucose |
| Respiratory quotient (RQ) |
ratio of CO2 produced to O2 consumed |
| RQ for carb diet |
1 |
| What is the RQ of the brain? |
very close to 1.0 - prefers carbs |
| What is the RQ of a mixed diet? |
0.8 |
| What is the RQ of an all fat diet? |
0.7 |
| How many kg of fuel are needed for a 100 kg body? |
2300 kg fuel |
| BMR |
basal metabolic rate |
| What does BMR depend on? |
age, gender, amount of lean muscle mass, physical activity level, diet, hormones |
| What hormones dictate BMR? |
thyroid, epi, norepi |
| What is the metabolic energy of proteins and carbs? |
4 kcal/g |
| What is the metabolic energy of fat? |
9 kcal/g |
| Which state is anabolic? |
fed |
| Which state is catabolic? |
fasting |
| Where can glycogen be stored? |
liver and muscle |
| What is an anabolic state? |
moving into storage |
| What is the dominant anabolic hormone? |
insulin |
| Where is the glucose produced in a fasting state? |
liver |
| What forms of energy does the liver produce in a fasting state? |
ketones, glucose |
| What is a catabolic state? |
breaking down stored fuel and breaking them down into fuel - glucose and ketones |
| What are the dominant catabolic hormones? |
cortisol, epinephrine, glucagon |
| Where is excess energy store? |
liver, muscle, fat |
| What control anabolic vs catabolic pathways? |
hormones |
| What two hormones govern "minute to minute" maintenance? |
insulin and glucagon |
| What four hormones work under stress? |
cortisol, epinephrine, glucagon and growth hormone |
| What turns on stress hormones? |
drop in glucose |
| What governs metabolism under long term starvation? |
thyroid hormone |
| What does thyroid hormone do in starvation? |
downregulated basal metabolic rate, conserve energy |
| When do plasma glucose levels rise? |
after meals |
| What do plasma glucose levels do in sleep? |
fall |
| What effect do a rise in plasma glucose levels have on insulin? |
when glucose rises, insulin immediately goes up |
| What does glucagon do when insulin is up? |
low glucagon |
| Does insulin or glucagon go through larger variations? |
insulin - glucagon never jumps as much as insulin |
| How does the body regulate glucagon? |
very tightly |
| Where does a stimulus go in increased plasma glucose levels? |
stimulates release of insulin from beta cell |
Cardio Block2anatomy
