DIGESTION, ABSORPTION AND METABOLISM Flashcards
refers to the mechanical and chemical processes that convert nutrients into a physically absorbable state
digestion
Process through which foods are broken down into smaller units to prepare nutrients for absorption
digestion
2 Types of Digestion
- Chemical Digestion
- Mechanical Digestion
Chemical altering effects of digestive secretions, gastric juices and enzymes on food substance consumption
Chemical Digestion
The crushing, twisting effects of teeth and peristalsis that divide foods into smaller pieces
Mechanical Digestion
Swallowing of food
Deglutition
Deglutition begins in the _____________ and continues in the _____________ and _______________
mouth; pharynx; esophagus
__________________ and _________________ move food down the _________________
Peristaltic waves; mucous secretions; esophagus
Relaxation of the _____________________________________________________________ allows food to enter the stomach; contraction of this sphincter muscle prevents _______________________________ of stomach contents.
lower esophageal sphincter (gastroesophageal constrictor muscle); regurgitation (reflux)
Digestion begins in the ____________ (for CHO) and ________________, and is completed in the ___________________. This is accomplished by specific substances entering the duodenum: _________________________ through the _______________ duct, ___________ through the ______________________, and _____________________ produced in the __________________.
mouth; stomach; small intestines; pancreatic enzymes; pancreatic; bile; common bile duct; intestinal enzymes; jejunum
Stomach is ________________ in nature and the _________________ are alkaline in nature
acidic; intestines
pH of saliva
7
pH of gastric juice
2
pH of pancreatic juice
8
Process whereby nutrients are absorbed into blood or lymph circulation
Absorption
Process by which the end products of digestion—monosaccharides (simple sugars), amino acids, glycerol, fatty acid chains, vitamins, minerals, and water—pass through the epithelial membranes in the small and large intestines into the blood or lymph systems.
Absorption
Most absorption occurs in the __________________ through the processes of ____________________________________________.
small intestines; osmosis, diffusion, and active transport
The main functions of the large intestines are to ___________________________________________________
absorb water and collect food residue (dietary fiber).
the part of food that body enzymes cannot digest and absorb
DIETARY FIBER
absorbs water in the large intestine, promoting the formation of a soft, bulky stool
DIETARY FIBER
Aggregate of all chemical reactions and processes in every body cell, such as growth, generation of energy, elimination of wastes, and other bodily functions as they relate to the distribution of nutrients in the blood after digestion
Metabolism
converts all monosaccharides to glucose and excess amino acids to urea, carbohydrates, or fats.
Liver
The liver converts all monosaccharides to _______________ and excess amino acids to __________________________________________
glucose; urea, carbohydrates, or fats.
Excess fats are converted in the liver to _______________ and fatty acids, then to ________________________________
glycerol; acetyl coenzyme A (acetyl-CoA)
breakdown of glucose by enzymes located inside the cell’s cytoplasm.
Glycolysis
This process produces adenosine triphosphate (ATP) and pyruvate, which provide the cell with energy
Glycolysis
Glycolysis produces __________________________ and _____________, which provide the cell with energy
adenosine triphosphate (ATP); pyruvate
lactate is produced in the cytoplasm by an enzyme (lactate dehydrogenase);
Anaerobic metabolism
this type of metabolism takes place when the oxygen supply is limited, as in the muscles and red blood cells, which lack mitochondria.
Anaerobic metabolism
pyruvate enters the cell’s mitochondria and in the presence of oxygen is converted to acetylCoA.
Aerobic metabolism
Digestive and metabolic waste products are excreted through the ________________ and _______________.
intestines; rectum
The skin and sweat glands remove ________________________________________________; the lungs remove _____________________________.
water, toxins, salts, and nitrogen wastes; carbon dioxide and water
Anabolism
- Glycogenesis
- Gluconeogenesis
when the body produces energy (in the form of ATP)
using oxygen.
Aerobic Metabolism
a series of chemical reactions used by all aerobic organisms to generate energy through the oxidization of acetate—derived from carbohydrates, fats, and proteins —into carbon dioxide
Krebs cycle
Krebs Cycle is a a series of chemical reactions
used by all aerobic organisms to __________________ through the oxidization of _________—derived from _________________________________ —into ____________________
generate energy; acetate; carbohydrates, fats, and proteins; carbon dioxide
Catabolism
- Glycolysis
-Glycogenolysis
