Chapter 26: Nutrition and Metabolism

ghrelin

-hunger-arousing hormone secreted by an empty stomach -stimulates the hypothalamus to secrete growth hormone -hormone primes the body to take best advantage of the nutrients about to be absorbed -ceases within an hour of eating

oxidation of a typical fatty acid can yield ___ ATP

129

what are the 4 end products of glycolysis?

2 pyruvic acid + 2 NADH + (2H+) + 2 ATP

type I alcoholism usually sets in after age ____ and is associated with

25; peer pressure

fats should makeup ____% of the daily caloric intake

30%

How many ATP does glycolysis and aerobic respiration produce versus anaerobic fermentation?

38;2

the absorptive state lasts about _____ hours during and after a meal.

4 hours

fats yield ___ kcal/g; carbs and proteins yield ____ kcal/g

9;4

leptin

A chemical produced by the adipose cells that seems to signal that plenty of fat is stored and that no more fat is needed; this signal may diminish eating.

beta oxidation

A metabolic sequence that breaks fatty acids down to two-carbon fragments which enter the Krebs cycle as acetyl CoA.

acidosis

A pathologic condition resulting from the accumulation of acids in the body; can be fatal

shivering warms the body by ______________

ATP hydrolysis

NADH

An energy-carrying coenzyme produced by glycolysis and the Krebs cycle. NADH carries energy to the electron transport chain, where it is stored in ATP.

what is the overall chemical reaction equation for aerobic respiration?

C6H12O6 + 6 O2 = 6 CO2 + 6 H2O

urea is a nitrogenous waste made from _____ and ______________

CO 2 and ammonia

describe basic process of short-term appetite regulation

Figure 26.1

Bonus: see if you can "freestyle" describe the basic lipoproteins pathway

Figure 26.2 B

list the 3 *short-term* gut-brain peptides

Ghrelin, peptide YY, Cholecystokinin

chemiosmotic mechanism

H+ flow rushing through mitochondiral membrane providing energy for ATP synthesis- flow is from high proton concentration to low

insulin

Hormone produced by the pancreas that is released when stimulated by elevated glucose levels. This hormone decreases blood sugar levels by accelerating the transport of glucose into the body cells where it is oxidized for energy or converted to glycogen or fat for storage.

triglycerides

Large fat molecules composed of three parts fatty acid and one part glycerol; how most fat is stored

list the 2 *long-term* gut-brain peptides

Leptin and Insulin

________ is a three-sugar carbon that can be converted to glycerol.

PGAL (phosphoglyceroldehyde)

anaerobic fermentation

The metabolic pathway by which pyruvic acid (a byproduct of glycolysis) is converted to lactic acid; happens when there is no oxygen; less efficient.

deamination

The removal of an amino group (-NH2) from an amino acid or other organic compound.

what is glycolysis?

a metabolic process that breaks down carbohydrates and sugars through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP http://www.johnkyrk.com/glycolysis.html

complete proteins contain what?

all of the essential amino acids

glucagon

antagonist of insulin; release is stimulated by low blood glucose levels; stimulates the liver to break down its glycogen stores to glucose and release to the blood

What is a big biproduct of aerobic respiration?

carbon dioxide

membrane reactions

carried out in a series of reactions called the electron-transport-chain occurs in the inner membrane of the double membrane mitochondria Creates most ATP, 38 ATP per glucose!

cutaneous vasodilation

constriction or expansion of blood vessels to allow for heat retention or heat release

insulin glycogenolysis

conversion of glycogen to glucose when blood sugar is low

list functions of liver

convert ammonia to urea carry out beta oxidation synthesize cholesterol synthesize glucose from fats and amino acids

the quickest physiological means of heat loss is by ___________________________

cutaneous vasodilation

Where in the cell does glycolysis happen?

cytoplasm

to use an amino acid as fuel it must be ____________

deaminated

heat cramps are muscle spasms due to ________________________ from sweating

electrolyte imbalance

excess glucose can become ______

fat

epinephrine

fight-or-flight neurotransmitter; increases the conversion of glycogen to glucose in liver and muscle tissue in anticipation of stress; causes rise in blood glucose levels and an increase in the basal metabolic rate

___________ is also secreted by the ___________ and regulates the *postabsorptive* state

glucagon; pancreas

_____________ is the primary fuel during the absorptive state

glucose

during the postabsorptive state, glucagon promotes ____________ and ____________ to raise the blood glucose and free fatty acid levels

glycogenolysis; lipolysis

pyruvic acid is a product of what process?

glycolysis

What 2 different pathways can happen after glycolysis?

glycolysis --> (oxygen *not* available) --> anaerobic fermentation/lactic acid reduction OR glycolysis --> (oxygen available) --> aerobic respiration --> matrix reactions/Krebs --> membrane reactions/mitochondrial electron-transport chain

type II alcoholism is partially _______________

hereditary

cholecystokinin

hormone the small intestine (duodenum and jejunum) secretes to stimulate release of pancreatic juice from pancreas and bile from gallbladder

what are gut-brain peptides?

hormones that act as chemical signals from the gastrointestinal tract to the brain

adipocytes grow in adulthood by _______________

hypertrophy

___________is secreted by the __________ and regulates the absorptive state

insulin; pancreas

most tissue-protein turnover happens in the ______________

intestine

cirrhosis

irreversible disease characterized by degeneration of liver tissue, most often caused by alcoholism or a nutritional deficiency

What are chylomicrons?

made in the small intestinal cells; transport dietary lipids through the bloodstream to the liver

Factors that can lower metabolism include starvation and __________

mental state (apathy, depression)

most of the stored carbohydrate, glycogen, is found in ________ tissue

muscular

peptide YY

neuropeptide secreted in the small bowel (ileum) and colon; signals satiety (end of meal)

sugars function as the following 5 structural components:

nucleic acids glycoproteins ATP GTP cAMP

macronutrients

nutrients required in large amounts; carbohydrates, proteins, fats (lipids), water

What element/molecule is the final electron acceptor in aerobic respiration?

oxygen

ATP hydrolysis

process in which ATP is broken down and energy is harnessed

ATP synthase

protein structure in cell mitochondria that uses energy from H+ ions to convert ADP to ATP

at 70 F you lose most of your heat by _________

radiation

matrix reactions

reactions whose controlling enzymes are in the fluid of the mitochondrial matrix first principal group of reactions in aerobic respirations co2 released here primary source of co2 in breath largest part of matrix reactions is Krebs/citric acid cycle/tricarboxylic acid (TCA) cycle* (*before the Krebs Cycle begins, 2 pyruvate get converted into 2 acetyl-CoA with the help of Coenzyme A; 2 NADH & 2CO2 is produced)

what's the difference between short-term vs long-term gut-brain peptides?

short-term: act over a period of minutes to hours, managing hunger & satiety signals long-term: act over period of weeks to years, regulating body weight and metabolism

8 functions of lipids

store energy, insulation and cushioning for vital organs, vitamins, pigments, growth hormones, regulators, structural component of phospholipid bilayer in cell membranes, coat axons in brain (mylein)

glycogenesis

the conversion of glucose to glycogen when the glucose in the blood exceeds the demand

Where are low-density lipoproteins (LDLs) and high-density lipoprotens (HDLs) produced?

the liver (technically VLDLs -- Very Low-Density Lipoproteins -- are produced in the liver and then *converted* to LDLs later; HDLs just straight-up produced in the liver)

aerobic respiration

the process in which pyruvic acid is broken down and NADH is used to make a large amount of ATP

ketone bodies

the product of the incomplete breakdown of fat when glucose is not available in the cells; can cause acidosis

metabolism

the sum of all chemical processes that occur in an organism

lipogenesis

the synthesis of fat from other types of molecules

gluconeogenesis

the synthesis of glucose from noncarbs

starvation will lower your ___________________

total metabolic rate

what are the two categories of micronutirents?

vitamins and minerals

What kind of ratio of HDL to LDL is good for the body?

you would want a ratio of high HDL to low LDL