Lesson 3 Flashcards
The breakdown of food in the body in
preparation for absorption
Digestion
food is broken into
smaller pieces by teeth and moved along
the gastrointestinal tract by peristalsis.
Mechanical digestion
carbohydrates,
proteins, and fats are broken down with
the addition of water (hydrolysis) into
nutrients that tissues can absorb and use
Chemical digestion
act as a catalyst, which
speeds up the chemical reactions without
itself being changed in the process
enzyme
-Food travels through this
muscular tube.
-Connects mouth to stomach
- Peristalsis and gravity act to
move bolus
Esophagus
Chemical changes occur through?
hydrolysis
Enzyme that acts on starch.
(salivary amylase or ptyalin)
What symptom results when the cardiac
sphincter does not close properly? What is the name of the condition?
Indigestion or heartburn occurs as a result of
stomach acid flowing back into the
esophagus. This is called gastroesophageal reflux.
(food that is ready
to be swallowed
Bolus
It is the only organ that secretes the intrinsic factor for vitamin B12.
Stomach
funtion of intrinsic factor in the stomach
binds vitamin B12 so that it can be absorbed in the intestines
enzyme that breaks down proteins
pepsin
Temporary storage of food
Mixing of food with gastric juices
Regulation of a slow, controlled emptying
of food into the intestine
stomach
In children, ____ breaks down milk
proteins, and _____ breaks down
the butterfat molecules of milk.
rennin, gastric lipase
Identify the three parts of the stomach
fundus
body
pylorus
lack of intrinsic factors in the stomach can cause what disease
pernicious anemia
hormones that causes pancreas to release sodium bicarbonate to neutralize acidity of chyme.
secretin
Emulsifies fat after it is secreted into small
intestine
Produced in liver; stored in gallbladder
bile
pancreatic enzymes that split proteins
Pancreatic proteases (trypsin, chymotrypsin,
carboxypeptidases)
pancreatic enzymes that converts starches
(polysaccharides) to simple sugars
Pancreatic amylase
pancreatic enzymes that reduces fats to fatty acids and glycerol
Pancreatic lipase
enzyme found in SMALL INTESTINE that reduce proteins to amino acids
Peptidases
Prepares foods for absorption
Produces enzymes
Lactase, maltase, sucrase convert
lactose, maltose, sucrose to simple
sugars.
Small intestine
sections of small intestine
duodenum
jejunum
ilieum
Absorb water
Synthesize some B vitamins and vitamin K
Collect food residue
Large Intestine
why does large intestine do not get ulcer despite the acidity of chyme?
because colon walls secrete mucus to protect it
against acidic digestive juices in chyme.
it produces gastric acid
parietal cells
secretes hydrochloric acid
gastric pits
where does CARBOHYDRATE digestion starts?
mouth
where does FAT digestion starts?
small intestine
where does PROTEIN digestion starts?
stomach
The passage of nutrients into the blood or
lymphatic system.
Absorption
where does most absorption occurs?
small intestine
- a hairlike projections that increase surface
area for maximum absorption. - absorb nutrients from the chyme and
transfer them to the bloodstream.
Villi
type of metabolism that is also called oxidation, it combines nutrients WITH oxygen within each cell
Aerobic metabolism,
- The transformation of nutrients into energy
within the cell - Occurs after digestion and absorption;
- nutrients are carried by the blood to the cells
of the body
Metabolism
type of metabolism that reduces fats WITHOUT
the use of oxygen
Anaerobic metabolism
- Medical standard used to define obesity
- Used to determine whether a person is at
health risk from excess weight
Body Mass Index
The complete oxidation of carbohydrates,
proteins, and fats
Krebs cycle
the process of using energy
from oxidation to create new compounds.
Anabolism
is the breakdown of
compounds during metabolism
Catabolism
used to determine
the energy values of foods.
bomb calorimeter
- The rate at which energy is needed for
body maintenance - The energy necessary to carry on all
involuntary vital processes while the body
is at rest - Also known as resting energy expenditure
(REE)
Basal Metabolic Rate (BMR)
Basal Metabolic Rate (BMR)
-Factors that affect BMR: lean body mass,
body size, sex, age, heredity, physical
condition, and climate
-BMR is greater in men than women.
-BMR increases during growth and fever.
-BMR decreases with age and during
starvation.
Basal Metabolic Rate (BMR)
-Factors that affect BMR: lean body mass,
body size, sex, age, heredity, physical
condition, and climate
-BMR is greater in men than women.
-BMR increases during growth and fever.
-BMR decreases with age and during
starvation.
formula in calculating the BMR
Harris-Benedict equation
During metabolism, carbohydrates and
proteins are combined with oxygen in a
process called ___
oxidation
