Anatomy (digestive): Quiz 3 Flashcards
(25 cards)
6 nutrients that humans need
- Protein
- Fats (lipids)
- Carbs
- Water
- Vitamins
- Minerals
Define metabolism
All the chemical reactions that occur in living organisms needed to maintain life
Define catabolism
metabolic reactions that break down larger molecules into smaller subunits
Define anabolism
metabolic reactions that us energy to produce larger molecules from smaller substances
Define metabolic rate
rate at which body converts stored energy into working energy.
Depends on body size, physical activity, sex, age, hereditary
Function of carbs
main energy source for body
Composition of carbs
molecules containing atoms of CARBON, HYDROGEN + OXYGEN in a 1:2:1 ratio
Types of carbs
MONOSACCHARIDE: single sugar molecule (veggies/fruit/honey)
DISACCHARIDE: 2 sugar molecules joined together (milk+sugars)
POLYSACCHARIDE- complex carb made of many linked single sugars (rice/corn/wheat)
Carbs make up how much of our daily energy needs?
55%
Can humans digest fibre?
NO, but fibre helps in the elimination process
How are carbs stored?
carbs stored in liver and muscle tissue as glycogen. If too much glycogen, stored as body fat
Function of proteins
Key building blocks of cells. They do lots of things like…
- make up hormones
- help create bodily structures
- build hair, skin and nails
Composition of proteins
Long chains of AMINO ACIDS
Types of proteins
- 20 different types of amino acids
- human body can make 12
- 8 obtained from food (aka the ESSENTIAL AMINO ACIDS)
Proteins make up how much of our daily energy needs?
10-30%
How are proteins stored?
-when eaten, body separates proteins into individual amino acids so they can be rearranged for use
- humans unable to store excess protein
- EXCESS stripped of nitrogen base + converted into glycogen ——> glucose for energy (excess glucose stored as body fat)
Function of lipids
Concentrated energy source.
- helps absorb vitamins
- component of cell membrane
- insulation
- certain hormones are fats
Composition of lipids
made of 3 FATTY ACID CHAINS bonded to GLYCEROL
whole molecule called a TRYGLYCERIDE
Typed of lipids
SATURATED: usually solid @ room temp. Every carbon bonded to hydrogens, single bonds.
UNSATURATED: oils, usually liquid @ room temp. Some Cs not filled with Hs. Have carbon double bonds.
STEROID: sex hormones and cholesterol (essential for structure of cell membrane)
Tell me about cholesterol
- good and bad types
- essential substance for body
- too much is harmful
- this lipid structure is essential for structure of cell membrane
Lipids make up how much of our daily energy needs?
no more than 30%
How are lipids stored?
as fat in body (adipose tissue)
Digestion in mouth
Physical
-chewing
Chemical
-salivary glands release AMYLASE (digests carbs)
Digestion in esophagus
Physical only
-peristalsis