Metabolism/Nutrition Flashcards
nutrition is food, vitamins and minerals that are
ingested and assimilated into the body
the process of using nutrient molecules as energy sources and as building blocks for our own molecules
metabolism
metabolism includes 2 processes which are
catabolism
anabolism
The breakdown of complex compounds into simpler components
Catabolism
Describe anabolism
the building of simple compounds into needed substances (more complex compounds)
what are the most common energy sources
glucose and fatty acids
how many stages of glucose catabolism are there
2
cellular respiration is catabolism of nutrients to
release energy (generate ATP)
Glucose catabolism: Anaerobic phase is the first step in glucose breakdown known as
glycolysis
Anaerobic Phase (glycolysis) produces what
2 ATP per molecule of glucose
Pyruvic acid
Anaerobic phase aka glycolysis occurs in what part of a cell
Cytoplasm
Oxygen is required to further metabolize the products of anaerobic (glycolysis) phase. If no oxygen what is it converted to
Lactic acid
Aerobic phase of glucose catabolism is very controlled second step in glucose breakdown. it metabolizes
pyruvic acid
Aerobic phase of glucose catabolism occurs in the
mitochondria
Aerobic Phase of glucose catabolism produces (3)
32 ATP per molecule of glucose (most stored for future use, small amount released as heat)
Water
CO2
Fatty Acids are oxidized to generate energy through ___ mechanisms. Produces?
Aerobic mechanisms only
Produces ATP, water and carbon dioxide
What is deamination
Amine groups must be removed from amino acids before oxidation
deamination occurs where
liver
what is metabolic rate
rate at which cellular respiration converts nutrients int ATP (energy)
Metabolic rate is affected by determinants of health which are?
Diet
size
% of body fat
gender
age
activity level
hormones
Metabolic rates increase/decrease with age
decreases
what is basal metabolism
the amount of energy needed to maintain life functions while he body is at rest
what is the energy you expend each day just to stay alive
BMR (measured in kilocalorie; kcal)
BMR equation
BMR + (BMR x activity level)
in nutrient metabolism all chemical reactions require
enzymes as the catalyst
In nutrient metabolism some nutrients are built into body materials instead of
producing energy
what is a common energy source; most converted to glucose
Carbohydrates
Glucose is stored as? and where?
stored as glycogen
stored in muscle and liver
if there is too much glucose in the blood ?
it is converted to fat and stored (adipose tissue and the liver)
another major source of energy for most cells (not the brain!)
fats
Fats are catabolized using oxygen in the
mitochondria
what are ketone bodies
partially metabolized fatty acids
ketone bodies are produced by
the liver
the body does not store proteins as
fuel
specific proteins are synthesized by ___ to meet specific body needs
amino acids
if we do not have enough protein, it is taken from?
muscle tissue or plasma proteins (this is dangerous)
typical recommendations for % of calories in daily diet for fat
20-35%
Complex carbs are good, what do they do?
maintain blood sugar levels
what is the glycemic effect
how rapidly a particular food raises the blood glucose level and stimulates insulin release
glycemic effect is influenced by
combination of different foods and time of day it is being eaten
Simple sugars are metabolized rapidly they are good for
only a fast energy only (unhealthy; cause blood glucose levels to rise and fall rapidly)
Why is fiber a good thing (5)
-adds bulk to stool
-regulates the digestion & absorption of other carbs
- assists in weight management
-lowers cholesterol
-helps to prevent diabetes, colon cancer etc..
essential fatty acids must be taken in by food we eat. 2 essential fatty
Linoleic acid (easy to get; veg and veg oils)
Alpha-linoleic acid ( fatty fish, shellfish)
Saturated fats should be less than 1/3 of the fat in diet. These fats can lead to
cancer
heart disease
cardiovascular problems
Unsaturated fats are derived from plants; what are some examples
oils: corn, peanut, olive, canola
Partially hydrogenated fats are what
artificially saturated to prevent spoilage
*contains trans fatty acids
most animal proteins supply all of the
(9) essential amino acids> ‘complete proteins’
Some nonessential amino acids can become essential if
if our body can no longer produce them
Minerals are chemical elements needed for
body structure, fluid balance, muscle contraction, blood clotting and nerve impulses
what are trace elements
minerals needed in very, very small amounts
what are complex organic substances
vitamins
what vitamins are water soluble
B, C
what vitamins are fat- soluble
A, D, E, K
vitamin are essential for
metabolism
what do antioxidants do
defend against harmful free radicals
defend against aging and disease.
we can metabolize how much pure alcohol/hr
1/2 ounce
alcohol is rapidly absorbed through
stomach and small intestine
alcohol is detoxified by the
liver
food allergies involve the
immune system
food sensitivities are adverse reactions to specific foods and could be a result of what 2 things
-result of enzyme deficiency
-GI symptoms
Contributing factors of malnutrition include
poverty, old age, chronic illness, anorexia, poor dental health and drug and alcohol use
protein-energy malnutrition (PEM) reflects
reflects an overall dietary deficiency
Marasmus is
severe PEM in infancy and childhood
what is kwashiorkor
protein insufficiency common in toddlers.
weaned toddlers in poor countries (bulging tummy) Loss of intestinal villi
what is normal BMI range
18.5-24.9
Why is BMI not a fair indication of overweight/obesity in people
It does not account for muscle and fat composition in the body
Eating disorders stress the body. What can result?
Lack of estrogen in women
Loss of bone (osteoporosis)
Degeneration of myocardium
What happens with nutrition when we age
Metabolism slows down
Sense of taste and smell decreases
Vitamin d synthesis and calcium absorption declines
What is a byproduct of the reactions in our bodies (hint cellular respiration)
Heat
Asking if heat produced by the body depends on
Exercise
Hormone production
Food intake
Age
How much heat do we lose through the respiratory system, urine and feces
15-20%
How much heat is lost through the skin
80%
How do we prevent heat loss
Clothing (artificial)
Layer of fat under the skin (natural)
What does thermoregulation refer to
Body temperature remains fairly constant even when the conditions outside change
What regulates body temp by maintaining a balance between heat production and heat loss
The hypothalamus
What happens when there is too much heat loss (environment is too cold)
Shivering
Constriction of blood vessels
Who have a greater challenge regulating their body temperature
Very young and very old individuals
What is normal body temp
36.2-37.6°
How can fever be beneficial
Promotes phagocytosis
Inhibits growth of organisms
Increases metabolism
Fever terminology: lysis
Gradual drop in temp
Fever terminology: febrile
Having or showing signs of a fever
Fever terminology: pyrogens
Substances that produce fevers
Fever terminology: antipyretic drugs
Drugs that reduce fever
Not being able to maintain a constant body temp can be
Fatal
Heat associated disorders from least serious to most serious
Heat cramps
Heat exhaustion
Heat stroke
Hypothermia is an
Abnormally low body temp can be fatal
What results in local tissue damage
Frostbite
