Nutritional Biochem 1 Flashcards
powerhouse
Mitochondrion
DNA and RNA synthesis
Nucleus
protein synthesis
Ribosomes
Rough ER
protein synthesis
Smooth ER
lipid synthesis
Smooth ER in muscle cells;
site of Ca pump (muscle contraction)
Sarcoplasmic reticulum
Secretory vesicles; packaging of proteins
Golgi apparatus
catabolic functions:
◦Phagocytosis
◦Autolysis
◦Bone resorption
Lysosomes
oxidation and detoxification reactions
Peroxisomes
cell reproduction
Centrioles
___ is made up of nutrients.
Food
___ are the very essence of food.
Nutrients
Breaking down of food into absorbable form
Digestion
Absorbable form of Carbohydrates
Glucose (Sugars)
Absorbable form of Protein
Amino acids
Absorbable form of Fats
Fatty acids and glycerol
A continuous, coiled, hollow, muscular tube between the mouth and the anus, including the organs through which food passes for digestion and elimination as waste
Gastro Intestinal Tract (GIT)/ Alimentary Canal
Primary Roles of the GI Tract
- Receipt, maceration, & transport of ingested substances
- Secretion of digestive enzymes, acid, mucus, bile and other materials
- Digestion of ingested foodstuffs
- Absorption and transport of products of digestion
- Transport, storage and excretion of waste products
also called PHYSICAL change
Chewing/ Mastication
Swallowing
Elimination
MECHANICAL CHANGE
- Breakdown to simpler components with action of enzymes
- Absorption, metabolism and utilization
CHEMICAL CHANGE
Oral cavity; a mucous
membrane-lined cavity
Mouth
- muscular tube located in the neck, lined with mucous membrane.
- connects the nose and mouth with trachea (windpipe) and esophagus
- serves as a passageway for both air and food
Pharynx
Gullet; runs from the pharynx to the stomach (25 cm)
A passageway that conducts food to the stomach
Esophagus
C-shaped organ on the left side of the abdominal cavity (25 cm long)
Acts as a temporary storage tank for food and site for food breakdown
Stomach
result when the normal defense and repair system that protect mucosa of GI tract is disrupted.
Peptic Ulcers
Body’s major digestive and absorptive organ. extending from the pyloric sphincter to the ileocecal valve.
Small Intestine
what is the length of the small intestines?
2-4 m
what are the 3 subdivisions of he small intestines?
duodenum, jejunum, ileum
what is the length of the duodenum?
25 cm
what is the length of the jejuum?
2.5 m
what is the length of the ileum?
3.6 m
Wrinkled into hundreds of folds
VILLI
A villus-composed of hundred of cells covered with
MICROVILLI/brushborder
Ileocecal sphincter regulates the flow of material from the ileum, the last segment of the small intestine, into the \_\_\_\_.
cecum
The duodenum receives secretions from the gallbladder via the _____.
common bile duct.
The pancreas releases its secretions into the _____ _____, which eventually joins the
common bile duct.
pancreatic duct
regulates the flow of these secretions into the duodenum.
sphincter of Oddi
A tube which extends from the ileocecal sphincter to the anus.
Dry out indigestible food residue by absorbing water, and to eliminate residues as feces
Large Intestines/ Colon
what is the length of the Large Intestines?
1.5 m
Involved in the mastication (chewing) of food
Teeth
incisors
biting
canines
tearing
molars
grinding/ mashing
A soft triangular gland that extends across the abdomen from the spleen to the duodenum
Pancreas
where do the pancreas release digestive enzymes and juices
duodenum (exocrine)
Produces insulin and glucagon
(endocrine)
Largest gland in the body which overlies the stomach
-Functions include synthesis of bile salts, detoxification, excretion, and energy metabolism
Liver
A small, pear-shaped thin-walled green sac that stores and concentrates the bile
Gallbladder
gallbladder releases ____ when it receives a signal that ___ is present in the duodenum
bile,
fat
voluntary process of placing the food into the mouth before it can be acted on
Ingestion
movement of food form one digestive organ to the next
◦example: peristalsis, and mass movement
Propulsion
A periodic squeezing or partitioning of the intestine at intervals along its length by its circular muscle
Segmentation
Opens in response to swallowing
Upper Esophageal Sphincter
- a.k.a. cardiac sphincter
* Prevents gastric reflux
Lower Esophageal Sphincter
- Found at the bottom of the stomach
* Prevents intestinal contents from backing up into the stomach
Pyloric Sphincter
- Found at the end of the small intestine
* Empties the contents of the small intestine
Ileocecal Valve
Prevents elimination until you choose to perform
Anus
Transport of digested end products from the lumen of the GI tract to the blood or lymph
Absorption
(nucleoplasmand cytosol)-a solution composed of small amounts of gases, nutrients and dissolved water
Intracellular Fluid
(fluid that bathes the cell’s exterior)-a solution composed of rich amounts of nutrients, hormones, neurotransmitters, salts and waste products
Interstitial fluid
Substances are transported across the membrane without any energy input from the cell
PASSIVE TRANSPORT PROCESSES
Particles move from areas where they are most concentrated to regions where they are less concentrated to become evenly distributed
example: osmosis of water
Diffusion
Unassisted diffusion of solutes through the plasma membrane
◦small ions
◦small molecules of lipids
◦water
Simple Diffusion
A protein carrier is needed to allow the substances to move down their concentration gradient
◦water soluble vitamins
◦fructose
Facilitated Diffusion
The cells provides the metabolic energy (ATP) that drives the transport process
have to move uphill (against the concentration gradient) large molecules
non-fat soluble
glucose and amino acid
ACTIVE TRANSPORT PROCESSES
Some large molecules are
moved into the cell via engulfment by
the cell membrane
Pinocytosis.
soft, rounded chewed food
BOLUS
thick fluid mass, partially digested
CHYME
body’s solid waste matter
FECES
a coordinated activity of the tongue, soft palate, pharynx and esophagus
Deglutition or swallowing
Presence of food & pH releases
GASTRIN
It takes ___ hours for the stomach to move its contents to the small intestine
4 hours
Pylorus holds ___ mL of chyme and squirts _. __ mL of into the small intestine at a time. This is to allow for the intestines to process the contents
30 mL
3 mL
stimulates liver & pancreas
Secretin
stimulates gallbladder & pancreas
CCK (cholecystokinin)
inhibits stomach activity
GIP (gastric inhibitory peptide)
Water and end products of digestion are absorbed along the length of the ____ ____
small intestines
contain undigested food residues, mucus, bacteria and water
FECES-
Large intestines is limited to the absorption of vitamins, some ions & remaining water
True or False.
True
Entire network of chemical processes involved in maintaining life; encompasses all of the sequences of chemical reactions that occur in the body
METABOLISM
Used to indicate chemical changes which take place in the cells and tissues which are necessary for the fulfillment of vital functions of a living organisms
METABOLISM
building compounds: uses energy
Anabolic
breaking down compounds (releases energy)
Catabolic
Accomplished by the kidney, the colon, the skin and the lungs
EXCRETION
The elimination of indigestible substances from the body via the anus in the form of feces
Defecation
foods that contain live/active cultures of specific strains of bacteria
Probiotics
Capacity to do work
Measured in units known as calories (amount of energy required to raise the temperature of 1 mL of water at 15 OC by 1 OC)
Energy
kcal= calories?
1kcal= 4.184 kJ~ 4.2 kJ
Body building nutrients
Water Proteins Fats Carbohydrates Minerals
Nutrients that Regulate body processes
Carbohydrates Fats Proteins Vitamins Minerals Water
Organic (carbon-containing) nutrients
Carbohydrates
Proteins
Fats(Lipids)
Vitamins
Inorganic nutrients
Minerals
Water
Nutrients a person must obtain from food because the body cannot make them for itself in sufficient quantity to meet physiological needs
“indispensable nutrients”
ESSENTIAL NUTRIENTS
can be synthesized endogenously by the body
NON-ESSENTIAL NUTRIENTS
present in relatively high amounts in the body: 0.005% of body weight or above
MACRONUTRIENT
The Macronutrients
Carbohydrates Fats Proteins Water Major Minerals (> 5 grams): calcium, phosphorus, potassium, sulfur, sodium, chloride, magnesium
present in the body in amounts less than <0.005% of body weight
MICRONUTRIENT
