Nutrition and Metabolism Flashcards
Metabolism
- body’s use of food after circulated to cells
- as an energy source or as building blocks
Nutrition
- food we eat and nutrients they contain
- proper requires carbs, proteins, fats, vitamins, minerals
Assimilation
-when food molecules enter cells and undergo chemical change
Catabolism
- breaks molecules down
- release energy in the process
Anabolism
-build molecules into more complex compounds
Liver
- bile–>mechanical digestion of lipids
- role in metabolism of all 3 kinds of food
- maintain normal glucose
- plasma proteins
- synthesized by liver
- prothrombin and fibrinogen (blood clotting)
- albumin (maintain blood volume)
- detoxify various poisons
- store several substances (iron, vitamins A&D)
Carb Metabolism
- glucose metabolism
- metabolic pathway aerobic (requires oxygen)
ATP
- each glucose can form 36 ATP
- reusable energy storage and source for cellular work
Glycogenesis
- glucose anabolism
- glycogen (built up glucose and stored)
Glycogenolysis
-breaks down glycogen to release individual glucose
Hormones Regulate
- insulin–>lowers blood glucose level
- GH, hydrocortison, epi, glucagon all increase blood glucose
Glucose Metabolism
1) Glycolysis
- releases small amount of energy
- Anaerobic
- breaks down glucose into 2 pyruvic acid
2) Citric Acid Cycle
- pyruvic broken down into 2-C acetyl
- release high-energy electrons
- broken down into CO2
3) Electron Transfer System
- most energy of glucose released
Fat Metabolism
- primarily energy foods
- broken down into fatty acids and glycerol
- then converted into chemicals that enter citric acid cycle
- happens naturally when not eating carbs
- fats not needed for catabolism are anabolized to form triglycerides
- stored in adipose tissue
Protein Metabolism
- catabolized to release energy to small extent
- when fat reserves low
- AA converted to form glucose and enters citric acid cycle
- more commonly builds AA into complex proteins
- essential AA–>needed in diet
- nonessential AA–>made by body
Vitamin Metabolism
- organic molecules needed in small quantities
- most attach to enzymbes/coenzymbes and help them work properly
- body can store fat-soluble in liver, can’t store water-soluble
Mineral Metabolism
- attach to enzymes to help them work
- nerve conduction and muscle contraction (Na, Ca)
Basal Metabolic Rate (BMR)
- rate at which food catabolized under basal (normal) conditions
- number of calories/hr by catabolism to keep body alive, awake and warm
Total Metabolic Rate (TMR)
- total amount of energy used by body per day
- constant weight–> #of calories=TMR
- gain weight–> #of calories>TMR
- lose weight–> # of calories < TMR
Body Temperature
- thermoregulation–>maintaining homeostasis of body temp.
- Hypothalamus
- negative feedback mechanism to keep body temp. w/in normal
Skin
- when overheated, blood flow to skin increases, blood cooled
- heat lost by
- radiation
- conduction
- convection
- evaporation
- heat-generating muscle activities (shivering)
- secretion of metabolism-regulating hormones
