Unit 4 Digestive System Test

The primary role of the large intestine is _____________________________. As in nutrient absorption, water will pass from the lumen through the mucosa cells and into the bloodstream. The remaining dried out, indigestible waste is called ___________________. This process may take _______________!

The primary role of the large intestine is [water absorption]. As in nutrient absorption, water will pass from the lumen through the mucosa cells and into the bloodstream. The remaining dried out, indigestible waste is called [feces]. This process can take [12-24 hours].

The rectum is usually _______________, but when feces are forced in from the large intestine, the ________________________________ is initiated. The rectal wall contracts and both anal sphincters relax. However, if the timing is inconvenient, the brain can send a signal to the external anal sphincter (made of skeletal muscle) to constrict, temporarily delaying defecation

The rectum is usually [empty], but when feces are forced in from the large intestine, the [defecation reflex] is initiated. The rectal wall contracts and both anal sphincters relax. However, if the timing is inconvenient, the brain can send a signal to the external anal sphincter (made of skeletal muscle) to constrict, temporarily delaying defecation

The root is composed of dentin and contains extensions of the pulp called the _________________.

The root is composed of dentin and contains extensions of the pulp called the [root canal].

The root is the part of the tooth that is embedded in the ______________________

The root is the part of the tooth that is embedded in the [jaw bone].

The stomach is composed of _____ layers of _____________, each with muscle fibers that are oriented ____________________. This enables contractions to occur in many directions, allowing for the _____________ motions that contribute to mechanical digestion.

The stomach is composed of [3] layers of [smooth muscle], each with muscle fibers that are oriented [different directions]. This enables contractions to occur in many directions, allowing for the ["churning"] motions that contribute to mechanical digestion.

The surface of the mucosa and the top of each gastric pit contains cells that produce bicarbonate, an ___________________________. The bicarbonate mucus sticks to the stomach and prevents them from being digested by their own gastric juice by _____________ the acid.

The surface of the mucosa and the top of each gastric pit contains cells that produce bicarbonate, an [alkaline (basic) mucus]. The bicarbonate mucus sticks to the stomach and prevents them from being digested by their own gastric juice by [neutralizing] the acid.

The three muscle layers of the stomach are activated during chemical digestion when they are __________________________. As these three layers contract in various directions, the force compresses and mixes food until it has a uniform texture. As a result, the bolus will be turned into a thick-cream like fluid called _______________.

The three muscle layers of the stomach are activated during chemical digestion when they are [stretched by incoming food]. As these three layers contract in various directions, the force compresses and mixes food until it has a uniform texture. As a result, the bolus will be turned into a thick-cream like fluid called [chyme].

The wall of the GI Tract, from the esophagus to the large intestine, is made up of ___________ tissues layers (tunics).

The wall of the GI Tract, from the esophagus to the large intestine, is made up of [4] tissues layers (tunics).

The wall of the small intestine has 3 structures that enable it to perform the job of absorption: -__________________- folds of the wall of the small intestine -__________________-folds of mucosa -__________________-projections of the plasma membrane on each mucosal cell

The wall of the small intestine has 3 structures that enable it to perform the job of absorption: -[circular folds]- folds of the wall of the small intestine -[villi]-folds of mucosa -[microvilli]-projections of the plasma membrane on each mucosal cell

There are ____ total amino acids. The majority of amino acids can be made by the body, but __ of them cannot and therefore must be acquired from food. These 8 are called the _________________amino acids.

There are [20] total amino acids. The majority of amino acids can be made by the body, but [8] of them cannot and therefore must be acquired from food. These 8 are called the [essential dietary] amino acids.

Why are lipids essential to your health?

They provide and store energy, act as insulation, make up cell membranes, and help you absorb some vitamins and make hormones

Unsaturated fats are ________ and cannot pack closely together. As a result, usually ________________ at room temperatures

Unsaturated fats are [bent] and cannot pack closely together. As a result, usually [liquid (oil)] at room temperatures

Unsaturated fats are _______________ and important part of a balanced diet when consumed in moderation.

Unsaturated fats are [healthy fats] and important part of a balanced diet when consumed in moderation.

Unsaturated fats: fat molecules with _________________________.

Unsaturated fats: fat molecules with [1 or more double bonds].

What is the involuntary phase of swallowing?

Uvula blocks off nasal cavity, epiglottis folds over the trachea. Peristalsis moves the bolus into the esophagus.

What is the liver?

What is the liver? plays an important role in several different organ systems role in digestive system is to produce bile

When chewing, the _______________ and _____________ move food continuously between our teeth, which __________________ food into smaller fragments

When chewing, the [tongue] and [cheeks] move food continuously between our teeth, which [tear and grind] food into smaller fragments

What are the different categories of grains?

Whole grain Refined grains Enriched grains

___________ liters of gastric juice are produced each day! This production occurs in response to the sight, smell, and taste of food and the actual presence of food in the stomach.

[2-3] liters of gastric juice are produced each day! This production occurs in response to the sight, smell, and taste of food and the actual presence of food in the stomach.

________________ residing in the large intestine make their own enzymes, and they can break down some molecules that are indigestible to us.

[Bacteria] residing in the small intestine make their own enzymes, and they can break down some molecules that are indigestible to us.

_____________ is also secreted into the beginning portion of the small intestine where it will emulsify fat globules

[Bile] is also secreted into the beginning portion of the small intestine where it will emulsify fat globules

______________ is also a separate dietary nutrient which makes up ______________ of the food you eat.

[Water] is also a separate dietary nutrient which makes up [60%] of the food you eat.

What is the gallbladder?

a small green sac that is found on the inferior surface of the liver Bile made by the liver is stored here when digestion is not occurring

What is a nutrient?

a substance in food that the body uses to promote normal growth, maintenance, and repair

What is bile?

a yellow green salt solution that emulsifies fats (that is, breaks large fat globules into smaller ones) secreted from liver into small intestine through the bile duct

What are permanent teeth?

adult teeth -A full set of permanent (32 total*) is in place by the age 25 years old -The same number and arrangement of teeth exist in the upper and lower jaw

What is segmentation?

alternative contraction and relaxation of segments of the small intestine, resulting in mixing of the contents in each segment

What are deciduous teeth?

baby teeth -These teeth begin to erupt (break through the gums) around 6 months old -A full set of these teeth (20 total) is in place by age of 2 years old -These teeth fall out between ages of 6-12 years old

What is the voluntary phase of swallowing?

bolus is forced into the pharynx by the tongue

What is the pancreas?

gland that, in addition to its role in the endocrine system, also plays two important roles in digestion -produces enzymes that break down proteins, carbohydrates, and fats -produces alkaline fluid (basic) that neutralizes the acidic chyme coming from the stomach These substances are secreted from this into the small intestine through the pancreatic duct

What is peristalsis?

involuntary muscle contractions that propagate in a wave down the length of a tube

What is the gastrointestinal tract?

main organs of digestion; organs that process food through ingestion, propulsion, digestion, absorption, and defecation

What are the accessory organs?

organs that aid digestion but are not part of the gastrointestinal tract

How does the pharynx and esophagus propel food toward stomach?

peristalsis

What is the gingiva?

the gum

How does digestion in the mouth continue with chemical digestion?

via enzymes in saliva

Swallowing occurs in what 2 phases?

voluntary & involuntary phase

Factors to keep in mind when it coms to healthy proportions are ______________

-Exercise Regularly -Eat junk food sparingly

What are the major nutrients?

-carbohydrates -lipids -proteins

What are the processes which absorption occurs in the small intestine?

-diffusion -active transport

In what ways does form fit function in the small intestine?

-folding (circular folds, villi, microvilli) -length These things increase time and surface area for absorption

What does saliva contain?

-mucus: moistens and binds food -enzyme fluid: begins starch digestion in the mouth

Where are the enzymes that accomplish chemical digestion secreted from?

-pancreas -the mucosa cells lining the small intestine

What are minor nutrients?

-vitamins -minerals

To provide the body with adequate amounts of all the necessary nutrients, a variety of foods should be selected from each of the five major food groups:

1. Fruits 2. Vegetables 3. Grain products 4. Protein (meat + meat alternatives) 5. Dairy (milk and milk products

What are the functions of the digestive system?

1. Ingestion: to take in food from the environment 2. Propulsion: to move food from one organ to the next 3. Digestion: to break down food -Mechanical digestion: breaking down food by physical means, such as chewing, churning, or squeezing -Chemical digestion: breaking down food through the use of enzymes, acids, and bile 4. Absorption: to transport small particles from the lumen of the GI tract into the bloodstream 5. Defecation: elimination of indigestible waste from GI tract

What are the 4 categories of dietary lipids?

1. Saturated fat 2. unsaturated fat 3. trans fat 4. cholesterol

What are the five important accessory organs?

1. Teeth 2. Salivary glands 3. Pancreas 4. Liver 5. Gallbladder

What are the 2 sets of teeth that form throughout development?

1. deciduous teeth 2. permanent teeth

What are the 3 categories of all carbohydrates we digest from plants?

1. simple sugars 2. starches 3. fiber

What is the esophagus?

10 inch long, muscular tube that propel food from the pharynx, through the diaphragm and to the stomach

What is the appendix?

A vestigial organ, though to have played a role in digestion in our herbivorous evolutionary ancestors. This small pouch sometimes accumulates bacteria and becomes inflames (appendicitis), necessitating surgical removal

Why include fiber in the diet if it is indigestible?

Adds bulk to feces; this normalizes bowel movements Absorbs excess cholesterol, removing it from the body Station and weight control - fiber take up lots of volume but does not contain many calories, so you feel fuller longer without overconsumption of calories

Animal products contain the ______________, as they supply __________________________.

Animal products contain the [highest quality protein], as they supply [all eight essential amino acids the body requires].

At the bottom gastric pit contains a __________________. Cells in this gland secrete an enzyme that breaks down __________.

At the bottom gastric pit contains a [gastric gland]. Cells in this gland secrete an enzyme that breaks down [protein].

Avoid foods made with ________________.

Avoid foods made with [trans fat].

By-products that bacteria make from this process include ___________ such as methane and hydrogen sulfide (about 500 ml per day). These gases contribute to the _____________ of flatulence and feces.

By-products that bacteria make from this process include [gases] such as methane and hydrogen sulfide (about 500 ml per day). These gases contribute to the [odor] of flatulence and feces.

What is the stomach?

C shaped organ in the upper left region of the abdominal cavity Both types of digestion occur here: -mechanical digestion via squeezing and churning -chemical digestion via enzymes + acid ---> gastric juice

Carbohydrates are important as they are your body's main ___________________ and should contribute between 45-65% of your total calories.

Carbohydrates are important as they are your body's main [fuel source] and should contribute between 45-65% of your total calories

Chemical digestion of ________________________ occurs in the beginning portion of the small intestine.

Chemical digestion of [protein, carbohydrates, and fats] occurs in the beginning portion of the small intestine.

Cholesterol _____________ cell membranes.

Cholesterol [stablizes] cell membranes.

Cholesterol can build up in your arteries, causing _______________________.

Cholesterol can build up in your arteries, causing [atherosclerosis].

Cholesterol is the precursor for making important ________________.

Cholesterol is the precursor for making important [hormones].

Cholesterol is used by liver to make ______________.

Cholesterol is used by liver to make [bile].

Cholesterol: a waxy lipid formed from ____________________.

Cholesterol: a waxy lipid formed from [hyrdocarbon rings]

What is the muscularis layer of the GI tract?

Composed of two layers of smooth muscle, an inner circular layer and an outer longitudinal layer. As these two layers contract, they work together to propel food forward via a mechanism called peristalsis.

Consumption of trans fats increases risk of _________________________________.

Consumption of trans fats increases risk of [heart disease, stroke, diabetes, and inflammation].

What is the anus?

Distal opening of the GI tract. Contains two muscular sphincters to control the timing of defecation

During absorption, fully digested nutrients ___________________________________________ and then eventually into the ________________________, where they can then be delivered to cells around the body.

During absorption, fully digested nutrients [pass through the mucosal cells] and then eventually into the [bloodstream], where they can then be delivered to cells around the body.

What is the uvula?

During swallowing, closes off nasal cavity to prevent food from entering the nose

What is the epiglottis?

During swallowing, closes off the trachea to prevent food from entering the lungs

Why do you chew food?

Eases swallowing and makes the rest of digestion easier by exposing more surface area to be acted upon by digestive enzymes

Fiber is a complex carbohydrate made of long chains of sugars that are _____________________ to humans.

Fiber is a complex carbohydrate made of long chains of sugars that are [indigestible] to humans

Foods high in saturated fat should be consumed in ________________________.

Foods high in saturated fat should be consumed [in limited quantities]!

What are whole grains?

Foods that are made using the entire grain kernel (bran, germ, and endosperm) -Try to choose carbohydrates that are whole grain!

What are the refined grains?

Foods that are milled (removes the bran and the germ) -Results in a finer texture and longer shelf life -BUT also removes healthy fiber, iron, and B vitamins -Avoid these where possible-these are packed with calories but low on nutrients

What are enriched grains?

Foods that are milled but with the B vitamins and iron added back -Fiber is not added back

Fruits and Vegetables make up ______________ the plate (with more vegetables than fruit)

Fruits and Vegetables make up [half] the plate (with more vegetables than fruit)

What are the 2 main groups of organs of the digestive system?

Gastrointestinal tract and Accessory organs

Grains and protein make up ______________ the plate (with more grains, preferably whole grains)

Grains and protein make up [half] the plate (with more grains, preferably whole grains)

Humans produce about ____________ of saliva per day!

Humans produce about [1 liter] of saliva per day!

In addition to enzymes, the pancreatic juice arriving through the pancreatic duct into the small intestine contains bicarbonate ions (basic- pH 8) to ___________________ the acidic chyme coming from the stomach.

In addition to enzymes, the pancreatic juice arriving through the pancreatic duct into the small intestine contains bicarbonate ions (basic- pH 8) to [neutralize] the acidic chyme coming from the stomach

In addition to these dietary source, your own _________________ supplies your body with cholesterol.

In addition to these dietary source, your own [liver] supplies your body with cholesterol

In the process of making a trans fat, the healthy bend in the unsaturated fat becomes _______________________________. As a result, trans fats have properties more like _______________ fats than unsaturated fats

In the process of making a trans fat, the healthy bend in the unsaturated fat becomes [straightened out]. As a result, trans fats have properties more like [saturated] fats than unsaturated fats

It takes ________________ for absorption of a meal to occur along the length of the small intestine. At the end of the small intestine, all that remains is indigestible food, water, and bacteria

It takes [3-6 hours] for absorption of a meal to occur along the length of the small intestine. At the end of the small intestine, all that remains is indigestible food, water, and bacteria

Junk almost always comes in the form of ________________________.

Junk almost always comes in the form of [processed food].

Junk food typically contains a large amount of _______________________________________________________.

Junk food typically contains a large amount of [salt, sugar, high fructose corn syrup, saturated fat, refined flour and corn].

Junk food: foods that contribute a lot of ____________________ but little _________________ or _________________, which leads to ______________________.

Junk food: foods that contribute a lot of [calories] but little [nutritional value] or [satiation], which leads to [weight gain].

What is the large intestine?

Large diameter, 5ft long tube connected to the distal end of the small intestine -Water absorption occurs here. As a result, the indigestible chyme remaining in the large intestine dries out and solidifies into feces

Legumes, nuts, and grains are ___________________ sources of protein. However, by ________________ these foods together, the eight essential amino acids can be obtained

Legumes, nuts, and grains are [incomplete] sources of protein. However, by [combining] these foods together, the eight essential amino acids can be obtained

What is the mouth (oral cavity)?

Location of ingestion. Additionally both types of digestion start here: -mechanical digestion via chewing (mastication) -chemical digestion via enzymes in salivaLocation of ingestion.

What is the small intestines?

Longest section of the GI tract (7-13 ft) which receives chyme (partially digested food) from the stomach -mechanical digestion via squeezing + churning -chemical digestion via enzymes + bile -nearly all absorption of nutrients

What is the tongue?

Manipulate food within the mouth (also serves as a sensory function)

Mechanical digestion occurs in the small intestine through the process of ___________________________.

Mechanical digestion occurs in the small intestine through the process of segmentation.

Minerals are foods that are mineral rich including _______________________.

Minerals are foods that are mineral-rich including [vegetables, legumes, milk, and some meats].

No one food contains all the required vitamins- thus, ______________ is the best way to ensure adequate amounts of all essential vitamins

No one food contains all the required vitamins- thus, [a varied and balanced diet] is the best way to ensure adequate amounts of all essential vitamins

Once proteins, carbohydrates, and fats are digested down to their smallest particles, _____________________ must occur.

Once proteins, carbohydrates, and fats are digested down to their smallest particles, [Absorption] must occur.

Only a small amount of food can be processed by the small intestine at a time. The _________________________ controls the amount of chyme entering the small intestine and prevents it from being overwhelmed. It takes ______________ (or more) to empty the contents of the stomach into the small intestine

Only a small amount of food can be processed by the small intestine at a time. The [pyloric sphinctor] controls the amount of chyme entering the small intestine and prevents it from being overwhelmed. It takes [4 hours] (or more) to empty the contents of the stomach into the small intestine

Other cell in the gastric gland produce _______________ (pH 1-3) which by itself ____________________, but also ____________________________________________________.

Other cell in the gastric gland produce [hydrochloric] (pH 1-3) which by itself [aids digestion], but also [triggers activation of the enzyme pepsin].

What is the serosa layer of the GI tract?

Outermost layer of the GI tract. Composed of loose connective tissue covered by squamous epithelium.

Partially digested food (_______________) is released into small intestine in a controlled manner through the contraction and relaxation of a ring of muscle called the ___________________.

Partially digested food ([chyme]) is released into small intestine in a controlled manner through the contraction and relaxation of a ring of muscle called the [pyloric sphinctor]).

Proteins are primarily used by the body to ____________________________. They are long chains made of individual units called ______________.

Proteins are primarily used by the body to [build structures]. They are long chains made of individual units called [amino acids]

Rugae can be stretched out, allowing stomach to ____________________ to accommodate incoming food. A full stomach can hold up to 4 lets of food!

Rugae can be stretched out, allowing stomach to [increase its capacity] to accommodate incoming food. A full stomach can hold up to 4 lets of food!

Saturated fat: fat molecules with ________________________.

Saturated fat: fat molecules with [no double bonds].

Saturated fats are ___________and can pack closely together.As a result, usually ___________ at room temperature.

Saturated fats are [linear] and can pack closely together.As a result, usually [solid] at room temperature.

What are molars?

Shape: Broad, flat Function: Crushing, grinding Deciduous number: 4 upper 4 lower Permanent number 6 upper 6 lower

What are premolars?

Shape: Broad, flat Function: crushing, grinding Deciduous number: none Permanent number: 4 upper, 4 lower

What are incisors?

Shape: chisel Function: cutting Deciduous number: 4 upper, 4 lower Permanent number: 4 upper, 4 lower

What are canines?

Shape: fang Function: piercing, tearing Deciduous Number: 2 upper, 2 lower Permanent number: 2 upper, 2 lower

What is the rectum?

Short muscular canal attached to the distal end of the large intestine Contracts to expel feces during defecation

Simple sugars are __________________________, but they do not usually supply any other nutrients.

Simple sugars are [quick energy source] , but they do not usually supply any other nutrients

What are sources of saturated fat?

Sources: Animal fat, butter, margarine, shortening, cheese, coconut oil

What are the sources of protein?

Sources: Eggs, Milk, fish, meat

What are the sources of trans fats?

Sources: Foods that are battered and fried, packaged baked goods, processed snack foods (look for the terms "trans fat" or "partially hydrogenated vegetable oil" on the label

What are the sources of simple sugars?

Sources: Fruit, honey, milk ( lactose- milk sugar is the only non-plant sugar in the diet), sugar cane, high fructose corn syrup

What are the sources of starch?

Sources: Grains, root vegetables, legumes (beans, peas, and lentils)

What are the sources of fiber?

Sources: Vegetables of all types, whole fruit, whole grains, legumes

What are the sources of unsaturated fats?

Sources: fish, nuts and seeds, vegetable oils (olive, avocado, canola, safflower)

Starch is a complex carbohydrate made of ________________________________ that must be broken down before they can be used for energy.

Starch is a complex carbohydrate made of [long chains of sugars] that must be broken down before they can be used for energy

What is the submucosa layer of the GI tract?

Surrounds the mucosa. Composed of connective tissue and contains nerves and blood vessels

How and why do people cough?

Talking/laughing while swallowing may interfere with the action of the epiglottis or uvula, causing food to enter the respiratory passageways. This triggers a protective reflect to expel food: coughing.

The _____________ connects the stomach to its superiomedial side.

The [esophagus] connects to the stomach on its superiomedial side.

What does "You are what you eat" mean?

The building blocks used to make the cells, tissues, and organs of your body are acquired from food The metabolic fuel that powers each cell comes from the utilization of energy stored in food This is is used to make ATP in the process of cellular respiration.

The combination of HCI and enzymes secreted from the gastric glands is called ____________________.

The combination of HCI and enzymes secreted from the gastric glands is called [gastric juice].

What is the pharynx?

The common passageway for food, water, & air -It will divide inferiorly into the trachea (respiratory system) and the esophagus (digestive system)

What are the 2 main regions of the tooth?

The crown The root

What is the mucosa layer of the GI tract?

The deepest layer of the GI tract. The mucosa lines the lumen and is composed primarily of epithelium

The enzymes in the saliva that help digestion continue in the mouth with chemical digestion specifically target __________ and break them down into simple _________.

The enzymes in the saliva that help digestion continue in the mouth with chemical digestion specifically target [starches] and break them down into [simple sugars]

The main source of lipids in the diet are triglycerides (neutral fats). Fats are higher in calories than other foods, so fat intake needs to be ______________________ with other nutrient sources.

The main source of lipids in the diet are triglycerides (neutral fats). Fats are higher in calories than other foods, so fat intake needs to be [balanced] with other nutrient sources

The mixture of partially digested food and saliva leaves mouth is called ___________.

The mixture of partially digested food and saliva leaves mouth is called [bolus].

The mucosa (innermost layer) of the stomach is wrinkled into large folds called ______________.

The mucosa (innermost layer) of the stomach is wrinkled into large folds called [rugae].

The mucosa of the stomach is composed of _____________________. This epithelium is arranged so that it forms numerous ______________.

The mucosa of the stomach is composed of [simple columar epithelium]. This epithelium is arranged so that it forms numerous [gastric pits].

What does the gingiva consists of?

The outermost, hard ceramic-like layer: enamel -The underlying bone-like material: dentin -The soft, innermost pulp which contains blood vessels and nerves