Nutrition Flashcards
Study of nutrients and how body uses them
Nutrition
Chemicals from the environment that organisms need for supply survival
Supplies energy to fuel metabolic processes, and for building blocks for producing the molecules the body needs
Nutrients
Getting big
Anabolic metabolism
Breaking down
Catabolic metabolism
Required in large quantities, such as carbohydrates, lipids, proteins; provide energy
Macronutrients
Required in small amounts, such as vitamins and minerals; help extract energy from macronutrients
Micronutrients
the body cannot synthesize or cannot synthesize in sufficient quantity
Must be obtained from the diet
Essential Nutrients
Units of heat used to express amount of energy in foods
Calories
Organic compounds, such as sugars and starches
Carbohydrates
Complex carbohydrates, such as starch from plant foods and glycogen from meats
Polysaccharides (carbohydrate sources)
milk sugar, cane sugar, beet sugar, molasses
Disaccharides (double sugars) (carbohydrate sources)
from honey and fruits
Monosaccharides (single sugars) (carbohydrate sources)
Three types of monosaccharides absorbed from digestive tract
fructose, galactose, and glucose
What does glucose get broken down into when needed
CO2, H2O, and energy
What happens to excess glucose?
converted into glycogen by glycogenesis, and stored in liver and muscle cells
If to much glucose is stored in the liver and muscle cells?
excess glucose is converted into fats by lipogenesis, and stored in the adipose tissue
Conversion of noncarbohydrates (amino acids, glycerol) to glucose, for cells that require glucose as energy source
Gluconeogenesis
Carbohydrate requirements
Primary source of fuel for cellular processes
carbohydrates varies with individual energy requirements intake of at least 125 to 175 grams/day is likely necessary
Average diet in the United States includes 200 to 300 grams/day
What are lipids?
Organic compounds that include fats, oils, phospholipids, and cholesterol
Supply energy for cellular processes
Serve as building blocks for structures such as cell membranes.
most commonly, fats/triglycerides
What are Triglycerides?
Composed of glycerol and 3 fatty acids
Most common dietary lipids
Also called “fats“
are found in plant-based and animal-based foods
What are Saturated fats?
Mainly in foods of animal origin, such as meat, eggs, milk, and lard
Also in palm and coconut oils
No double bonds between carbon atoms in fatty acids
Associated with increased risk of cardiovascular disease
What are unsaturated fats?
Found in seeds, nuts, and plant oils
Contain one or more double bonds between carbon atoms
What is the healthiest fat?
Monounsaturated
What is Cholesterol?
Abundant in liver and egg yolk
Some in whole milk, butter, cheese, and meats
Not found in foods of plant origin
What are some Functions of lipids? (TGE)
Mainly supply energy
Contain more than twice as much chemical energy per gram as carbohydrates or proteins
Triglycerides are broken down to glycerol and fatty acids, in order to release energy
Glycerol and fatty acids can be used to synthesize storage fats in adipose tissue
Excess glucose or amino acids can also be converted into fat molecules
these must be obtained from the diet
essential fatty acids
Lipids can combine with proteins to form what?
lipoproteins
high triglyceride content
VLDLs (very low density lipoproteins) these should be low
high cholesterol content
LDLs (low density lipoproteins) these should be low
high protein content
HDLs (high density lipoproteins) these should be high
Who controls cholesterol level?
The liver
stores and releases triglycerides as needed
Adipose tissue
What do proteins consist of?
Amino acid
removed through deamination; they react to form urea, which is excreted in urine
Amino groups (-NH2)