Chapter 4- HN
Bicarbonate
Neutralizes stomach acid which it reaches the small intestine, thereby protecting the small intestine from damage by acid
What cells are responsible for smell?
Olfactory cells in nose- stimulated with chewing
Digestion
Process of breaking down foods into a form the body can use
organ system level
Several organs work together to perform a specific function (ex. digestive system)
An example of a probiotic is ________.
The bacteria in yogurt
Organ level
different tissues combine to form organs
lower esophageal sphincter
prevent backflow (reflux) of stomach contents into the esophagus
Bicarbonate is a base with an alkaline pH that neutralizes the acidity of chyme as it moves from the _______ to the _______.
stomach, small intestine
Excretion
the process by which wastes are removed from the body
Lymph ________.
transports fat-soluble particles from the intestinal tract to the general circulation
In the cells, chemical reactions convert the energy in glucose, fatty acids, and amino acids into
ATP
muscle tissue
Contract and relax and permits movement
In a type of transport called _______, absorptive engulf nutrients from the lumen of the GI tract and form a vesicle around the substance to bring it into the cell
Endocytosis
nervous tissue
Found in the brain and spinal cord. Transmits nerve impulses
The most common forms of ____________ are ulcerative colitis and Crohn's disease.
Inflammatory bowel disease
The stomach also produces an important substance called ___ that is important for the absorption of vitamin B-12.
Intrinsic factor
Bile storage is concentrated in the ____________ .
gallbladder
Bile is necessary for some nutrient digestion and absorption; bile is produced in the ____________ .
liver
The hepatic portal system delivers nutrients from the digestive tract to the ________.
liver
anal sphincter
prevent defecation until person desires to do so
With _________, the inflammation and ulceration can extend throughout the GI tract and the ulcer can form fistulae between areas intestine or even to organs outside the GI tract
Crohn's disease
Bile
Helps fat digestion by suspending tiny fat droplets in watery chyme in the small intestine known as micelles
Swollen veins of the rectum and anus are known as ____________ .
Hemorrhoids
Phagocytosis
Immune substances from human milk
Proteins are made of amino acids. T/F
True
With _______, recurring inflammation and ulceration occur in the innermost layer of the large intestine.
Ulcerative colitis
Gluten is best described as ________.
a protein found in wheat and related grains
Amylase
breaks down starch
Located near the throat, the ____________ is the flap of tissue that prevents food from entering the trachea.
epiglottis
In the process of swallowing, food cannot normally enter the trachea because the ________.
epiglottis covers the larynx
The primary nutrient that bile is responsible for digesting and absorbing is ____________ .
fat
Lipids are broken down into
fatty acids and glycerol
how does digestion begin?
food preparation (cutting), cooking, food is easier to chew & swallow and breakdown during digestion
A term that refers to the stomach is ____________ .
gastric
Gastrin, secretin, CCK, and gastric inhibitory peptide are examples of ________.
hormones
Functions of the large intestine include ________.
housing bacterial flora that keep the GI tract healthy, absorption of water and electrolytes, especially sodium and potassium, and the defecation of feces
An example of a prebiotic is ________.
inulin, a poorly-digested carbohydrate found in foods such as onions, garlic, and asparagus.
All absorbed nutrients eventually travel to the
liver
Organism level
organ systems make up an organism
The free movement of a nutrient from an area of higher concentration (in the lumen) to an area of lower concentration (in the absorptive cell) is called ______
passive diffusion
The primary site of nutrient absorption from the gastrointestinal tract is the
small intestine
The ______ layer of the GI tract wall contains glands, blood vessels, and nerves, whereas the ________ layer is the outermost layer that protects the GI tract.
submucosa; serosa
Most dietary fats will ________.
Enter the lymphatic system
Sphincter of Oddi
control the flow of bile from common bile duct into the small intestine
pyloric sphincter
control the flow of stomach contents into the small intestine
Epithilial tissue
covers outside and inside the body. Absorb nutrients, secrete important substances, excrete waste, and protect underlying tissues
The pancreas secretes lipase, amylase and proteases, which are all ____________ used to breakdown macronutrients.
enzymes
Located near the throat, the ____________ is the flap of tissue that prevents food from entering the trachea.
esophagus
Which of the following correctly traces the path of food through the gastrointestinal tract?
esophagus, stomach, small intestine
The movement of a nutrient down a concentration gradient into the absorptive cells with the help of a protein carrier is ______.
facilitated diffusion
Carbohydrates are broken down into
glucose
Experiencing ____________ two or more times per week may signal the more serious gastroesophageal reflux disease ( ____________ ).
heartburn, gerd
Muscular contractions occurring throughout the GI tract that move food along are collectively called
peristalsis
______ refers to the muscular contractions that move food along the gastrointestinal tract.
peristalsis
Hydrochloric acid is secreted in the
stomach
The villi found in the gastrointestinal tract ________.
Are fingerlike projections into the lumen of the small intestine Are covered with the brush border (microvilli) Contain cells that produce mucus, hormones, and enzymes Produce a large surface area for nutrient absorption
facilitated diffusion
Fructose
The gastric secretion pepsin is necessary for ________.
Protein digestion
The throat is otherwise known as the ____________ , an organ that is located at the back of the oral and nasal cavities.
pharynx
immune system function
protects the body from disease
At the base of the stomach is the ______ which controls the rate at which food leaves the stomach and enters the small intestine
pyloric sphincter
Digestive system overview
Digestion, absorption, exception, immune system function
At the beginning of a meal, the hormone _______ is secreted from the stomach; this hormone controls the release of _______.
Gastrin; HCI
active diffusion
Glucose and amino acids
connective tissue
Holding structures together, stores fat, and produces blood cells (ex. tendons and cartilage)
A mixture of carbon dioxide, oxygen, nitrogen, hydrogen, methane, and small amounts of sulfur can cause bloating and abdominal pain, also known as ____________ .
Internal gas
mucus
Lubricates and hold bolus together
Saliva
Lubricates food in preparation for swallowing
Enzymes
Promotes breakdowns of nutrients into components that are small enough for absorption
What cells are on the tongue?
Taste buds on the tongue and soft palate- contain taste-receptor cells (ex. Salty, sour, sweet...)
Absorption
Uptake of nutrients from the GI tract into the blood or lymph
Mucus
a thick fluid that protects body cells and lubricates digesting food to help it move smoothly down the GI tract
Transport of a nutrient against a concentration gradient requires both a protein carrier and the input of energy. This type of transport is called _______.
active absorption
A moistened mass of food swallowed from the oral cavity into the pharynx is called a(n) ____________ .
bolus
Lysozyme
breaks down bacteria
In the stomach, food becomes a very acidic, watery mixture containing enzymes that leaves the stomach a teaspoon at a time into the small intestine and is called _____
chyme
Passive diffusion
fat and water
lleocecal valve
prevents food from moving back into the small intestine once it has entered the large intestine