Nutrition chapter 3

DNA is the _________ _________ that contains directions for making substances, specifically proteins, the cell needs. This code book remains in the nucleus of the cell but sends its information to other cell organelles by way of a "messenger" molecule called ribonucleic acid (RNA).

"code book"

After initial exposure to an antigen, a __________ is created such that a second exposure to the substance will produce a more vigorous and rapid attack

"memory"

As an organ of the digestive system, it produces_________________ __________ a mixture of water, bicarbonate, and a variety of digestive enzymes capable of breaking apart carbohydrates, proteins, and fats into small fragments.

"pancreatic juice,"

Under normal circumstances, only a minor amount _____% of carbohydrate, protein, and fat escapes absorption to reach the large intestine

(5%)

Sphincter that is Under voluntary control

(external sphincter).

Following a meal, the stomach contents are emptied into the small intestine over the course of __to____ hours.

1 to 4

The body contains about _____ billion neurons.

100

Type __ diabetes is the most common form of diabetes (90% of all cases) and also has a strong link to obesity. Typically, a genetic tendency for type ___ diabetes is expressed once a person becomes obese but often not before, again illustrating that nurture affects nature.

2

The heart is a muscular pump that normally contracts and relaxes______ -______ times per minute when the body is at rest.

50 to 90

About one of every _________ people in North America has a defective gene that greatly delays cholesterol removal from the bloodstream.

500

The combined folds, villi, and microvilli in the small intestine increase its surface area ______ times beyond that of a simple tube

600

Some water remains in the material that enters the large intestine because the small intestine absorbs only ___% to ____% of the fluid it receives, which includes large amounts of GI-tract secretions produced during digestion.

70% to 90%

What are the substances that cells need to enable the tissues, made of individual cells, to function properly.

A big supply of energy derived from dietary carbohydrate, protein, fat, water, protein, minerals, vitamins, and oxygen.

_ _______ _____________ is a regulatory compound that has a specific site of synthesis from which it then enters the bloodstream to reach target cells, they are messengers of the body. They can be permissive (turn on), antagonistic (turn off), or synergistic (work in cooperation with another hormone) in performing a task. Some compounds must undergo chemical changes before they can be this.

A true hormone

a base that neutralizes the acidic chyme as it moves from the stomach into the duodenum.

Bicarbonate

____________ flows through the cardiovascular system, while __________ flows through the lymphatic system.

Blood lymph

A microscopic blood vessel that connects the smallest arteries and veins; site of nutrient, oxygen, and waste exchange between body cells and the blood.

Capillary

The body system consisting of the heart, blood vessels, and blood. This system transports nutrients, waste products, gases, and hormones throughout the body and plays an important role in immune responses and regulation of body temperature.

Cardiovascular system

_____________ digestion refers to the chemical breakdown of foods by acid and enzymes secreted into the GI tract.

Chemical

_______________ __________ (reactions) occur constantly in every living cell: The production of new substances is balanced by the breaking down of older ones.

Chemical processes

Protein tissue that holds different structures in the body together. Some body structures are made up of tendons and cartilage and forms part of bone and the nonmuscular structures of arteries and veins.

Connective

The fluid and organelles (except the nucleus) in a cell this is anaerobic.

Cytoplasm

The site of hereditary information in cells, directs the synthesis of cell proteins.

DNA

a complex disease with more than 200 genes identified as possible causes. Only sensitive and expensive testing can determine who is at risk.

Diabetes

System consisting of the GI tract and accessory structures (liver, gallbladder, and pancreas). This system performs the mechanical and chemical processes of digestion, absorption of nutrients, and elimination of wastes.

Digestive system

The body system consisting of the various glands and the hormones these glands secrete. This system has major regulatory functions in the body, such as reproduction and cell metabolism.

Endocrine system

how does the stomach prevents itself from being digested by the acid and enzymes it produces.

First, the stomach has a thick layer of mucus that lines and protects it. The production of acid and enzymes also requires the release of a specific hormone (gastrin). This release happens primarily when we are eating or thinking about eating. Last, as the concentration of acid in the stomach increases, hormonal control causes acid production to taper off.

During times of fasting, the kidneys even produce _______from certain amino acids. Thus, the kidneys perform many important functions related to nutrition and are a vital component of the body.

Glucose

The cell organelle near the nucleus that processes newly synthesized protein for secretion or distribution to other organelles.

Golgi complex

A hormone produced by the pancreas. Among other processes, insulin increases the synthesis of glycogen in the liver and the movement of glucose from the bloodstream into body cells.

Insulin

what are Parts of the endoplasmic reticulum are also involved in?

Lipid synthesis, detoxification of toxic substances, and calcium storage and release in the cell.

A clear fluid that flows through lymph vessels; carries most forms of fat after their absorption by the small intestine.

Lymph

A system of vessels and lymph that accepts fluid surrounding cells and large particles, such as products of fat absorption. Lymph eventually passes into the bloodstream from the this system.

Lymphatic system

_______________ digestion takes place as soon as you begin chewing your food and continues as muscular contractions simultaneously mix and move food through the length of the GI tract

Mechanical

Organelles that are the main sites of energy production in a cell. They contain the pathway for oxidizing fat for fuel, among other metabolic pathways this is aerobic.

Mitochondria

Generally, the ability to move spontaneously. It also refers to movement of food through the GI tract

Motility

The digestive system is composed of six separate organs

Mouth Esophagus Stomach Small intestine Large intestine

A type of tissue adapted to contract to cause movement.

Muscle tissue

Tissue composed of highly branched, elongated cells that transport nerve impulses from one part of the body to another.

Nervous tissue

A group of tissues designed to perform a specific function; for example, the heart, which contains muscle tissue, nerve tissue, and so on.

Organ

Compartments, particles, or filaments that perform specialized functions within a cell.

Organelles

absorptive cells literally engulf compounds (phagocytosis) or liquids (pinocytosis). A cell membrane can form an indentation of itself so that when particles or fluids move into the indentation, the cell membrane surrounds and engulfs them.

Phagocytosis and pinocytosis

The fluid, extracellular portion of the circulating blood. This includes the blood serum plus all blood-clotting factors. In contrast, serum is the fluid that remains after clotting factors have been removed from __________.

Plasma

The blood that flows through the cardiovascular system is composed of what ...............

Plasma, red blood cells, white blood cells, platelets, and many other substances.

______________ on the outside surface of the membrane act as receptors, snagging essential substances that the cell needs and drawing them into the cell. Others act as gates that open and close to control the flow of various particles into and out of the cell.

Proteins

What does the brain do?

Stores information, reacts to incoming information, solves problems, and generates thoughts.

the primary taste sensations we experience are

Sweet, sour, salty, bitter, and umami comprise

Name an example of how the production of new substances is balanced by the breaking down of older ones.

The constant formation and degradation of bone.

___________ and _____________ we consume, for the most part, must undergo extensive alteration by the digestive system to provide us with usable nutrients.

The foods and beverages

The ___________ and the ________________, the way the genome is marked and packaged inside a cell's nucleus, control the expression of individual traits, such as height, eye color, and susceptibility to many diseases.

The genome and the epigenome

What is directed by genes present in the cells?

The growth, development, and maintenance of cells, and ultimately of the entire organism

These organs secrete digestive fluids into the GI tract and enable the process of converting food into absorbable nutrients.

The liver, gallbladder, and pancreas

__________, _______________,_____________ work with the GI tract and are considered accessory organs to the process of digestion

The liver, gallbladder, and pancreas

__________ hormones, help to control the body's rate of metabolism.

Thyroid

what kinds of things are harmful to the kidneys.

Uncontrolled diabetes, hypertension, and drug abuse

What do neurons allow us to perceive ?

What is occurring in our environment, engage in learning, store vital information in memory, and control the body's voluntary (and involuntary) actions.

One of the formed elements of the circulating blood system these cells are able to squeeze through intracellular spaces and migrate. They phagocytize bacteria, fungi, and viruses, as well as detoxify proteins that may result from allergic reactions, cellular injury, and other immune system cells.

White blood cells

The proper function of the kidneys is closely tied to the strength of the cardiovascular system, particularly its ..........................

ability to maintain adequate blood pressure, and the consumption of sufficient fluid.

The enzymes of the digestive system work together to hasten the breakdown of ingested food into ______________ ______________.

absorbable nutrients

Nutrients from the food we eat must pass through the walls of the GI tract—from the lumen through the cells lining the GI tract—to be ................

absorbed into the bloodstream.

The process by which substances are taken up from the GI tract and enter the bloodstream or the lymph.

absorption

intestinal cells that line the villi and participate in nutrient absorption.

absorptive cells

Besides working on only specific types of chemicals, enzymes are sensitive to ..................................... they require to function.

acidic and alkaline conditions, temperature, and the types of vitamins and mineral

The primary function of the lower esophageal sphincter is to prevent the__________ _____________of the stomach from flowing back up into the esophagus.

acidic contents

As chyme moves from the stomach into the first part of the small intestine, it is still very _________

acidic.

In addition to the need for a carrier protein, some nutrients also require energy input to move from the lumen of the small intestine into the absorptive cells. This mechanism makes it possible for cells to take up nutrients even when they are consumed in low concentrations (i.e., against a concentration gradient). Some sugars, such as glucose, are actively absorbed, as are amino acids.

active absorption

The main energy currency for cells. ATP energy is used to promote ion pumping, enzyme activity, and muscular contraction.

adenosine triphosphate (ATP)

Most fat is stored in ______________ ________, made up of cells designed specifically for this.

adipose tissue

Requiring oxygen.

aerobic

Peroxisomes also play a minor role in metabolizing one possible source of energy for cells which is.........

alcohol

Digestive enzymes that work in the acidic environment of the stomach do not work well in the ___________ _______________of the small intestine.

alkaline environment

____ cells contain mitochondria; only the size, shape, and quantity vary.

all

In the second route, the oxygenated blood circulates from the left side of the heart to ________ ________ ________ ________, eventually returning back to the right side of the heart. After blood has circulated throughout the body, it is ___________________.

all other body cells deoxygenated.

Each gene essentially represents a recipe, noting the ingredients (_________ _______) and how those ingredients should be put together (___ ________ ________).

amino acids to make proteins

A starch-digesting enzyme produced by salivary glands and the pancreas

amylase

Not requiring oxygen

anaerobic

A group of two sphincters (inner and outer) that help control expulsion of feces from the body.

anal sphincters

Blood protein that binds foreign proteins found in the body

antibody

Any substance that induces a state of sensitivity and/or resistance to microorganisms or toxic substances after a lag period; foreign substance that stimulates a specific aspect of the immune system.

antigen

Last portion of the GI tract; serves as an outlet for the digestive system.

anus

A blood vessel that carries blood away from the heart.

artery

Most of the processes of digestion and absorption are under ...........................................

autonomic control, and are involuntary.

The large intestine is home to a large population of ___________ (over _____ different species). While the stomach and small intestine have some bacterial activity, the large intestine is the organ most heavily colonized with bacteria.

bacteria 500

obtaining your nutrients primarily (or exclusively) from a ___________ ________ is the safest means to acquire the building blocks you need to maintain the good health of all organ systems.

balanced diet

A liver secretion stored in the gallbladder and released through the common bile duct into the first segment of the small intestine. It is essential for the digestion and absorption of fat.

bile

In addition to bile, the liver releases many other unwanted substances that travel with the bile to the gallbladder and end up in the small intestine and eventually in the large intestine for excretion. The liver functions in this manner to remove unwanted substances from the __________.

blood

The gene-diet interactions being discovered for cardiovascular disease, particularly the cases of high _______ ____________ levels, will likely be the first to lead to nutrition plans personalized to decrease cardiovascular disease risk

blood lipid

Unlike most veins in the body—which carry blood back to the heart—this portal vein leads directly to the liver. This enables the liver to process absorbed nutrients before they enter the general circulation of the ______________.

bloodstream

Chemical and mechanical digestive processes alter food so that the nutrients can be released and absorbed into the body for distribution to ________ __________.

body tissues

Most obese North Americans have at least one obese parent. This strongly suggests a genetic link. Findings from many human studies suggest that a variety of genes (likely 60 or more) are involved in the regulation of _________ ___________.

body weight

A moistened mass of food swallowed from the oral cavity into the pharynx.

bolus

Because obesity increases the risk of several forms of __________, a long- standing excess calorie intake is also a risk factor.

cancer

Undigested food ___________ be absorbed into cells of the small intestine

cannot

Once absorbed, water-soluble compounds such as glucose and amino acids are transported by the ______________ to the __________ _____.

capillaries to the portal vein

Membrane contains __________________ that mark the exterior of the cell. They are combined with either protein or fat, and they help send messages to the cell's organelles and act as identification markers for the cell. They detect invaders and initiate defensive actions. They important to cellular identity and interaction.

carbohydrates

The chyme is moved through the small intestine by peristaltic contractions so that it can be well mixed with the digestive juices of the small intestine. They contain many enzymes that function in the breakdown of ..........................for absorption.

carbohydrates, protein, and fat, as well as in the preparation of vitamins and minerals

The body has two separate organ systems that circulate fluids in the body and they are...............

cardiovascular system and the lymphatic system

a protective enzyme called _________ prevents excessive accumulation of hydrogen peroxide in the cell, which would be very damaging.

catalase

The large intestine (sometimes called the colon) can be subdivided into five main segments

cecum, ascending colon, transverse colon, descending colon, and sigmoid colon

a self-contained, living entity

cell

The ____ _____________ itself is not an organelle, but it holds the cellular contents (cytoplasm and organelles) together and regulates the flow of substances into and out of the cell. Cell-to-cell communication also occurs by way of this membrane.

cell membrane

Hormones are not taken up by all cells in the body but only by those with the correct receptor protein. These binding sites, which generally are found on the _______ __________, are highly specific for a ________ _________.

cell membrane certain hormone

An organelle bound by its own double membrane and containing chromosomes, the genetic information for cell protein synthesis and cell replication.

cell nucleus

Living organisms are made of many different kinds of _________ specialized to perform particular functions, and all cells are derived from preexisting cells.

cells

If food instead travels down the trachea, ______________ may occur

choking

Another component of the cell membrane that is fat soluble, so it is embedded within the bilayer and provides rigidity and thus stability to the membrane.

cholesterol

A single, large DNA molecule and its associated proteins; contains many genes to store and transmit genetic information.

chromosome

The genetic material in a cell nucleus includes many .......

chromosomes

The causes of__________ ___________are complex and include a significant genetic component. Fortunately, scientific breakthroughs in our understanding of the links between nutrition and genetics are beginning to touch our lives

chronic diseases

A mixture of stomach secretions and partially digested food.

chyme

Water-soluble nutrients are transferred to the _____________ ________ through capillary beds. Once absorbed through the stomach or intestinal wall, nutrients reach one of two destinations. Some __________ are taken up by cells in the intestines and portions of the stomach to nourish those organs.

circulatory system nutrients

The strains bifidobacteria and lactobacilli are typically associated with health, whereas ______________ are considered problematic.

clostridia

While our genome contains the _______ for the proteins that can be made by our bodies, our epigenome is an extra layer of instructions that influences gene activity.

code

The absorptive cells have a short life. New intestinal absorptive cells are constantly produced in the .............. and appear daily along the surface of each villus "finger."

crypts of the small intestinal lining

The metabolism of energy production begins in the ___________ with the initial anaerobic breakdown of glucose. The remaining aerobic steps of energy production take place in the mitochondria.

cytoplasm

A small amount of energy for use by the cell can be produced by chemical processes that occur in the ____________. This contributes to the survival of all cells and is the sole source of energy production in _____ _______ cells.

cytoplasm red blood

Starting at infancy, the_______plays a major part in determining the type of bacteria in our digestive tracts.

diet

Process by which large ingested molecules are mechanically and chemically broken down to produce basic nutrients that can be absorbed across the wall of the GI tract.

digestion

These vessels pick up and transport the majority of products of fat __________and fat ___________. These fat-related products are too large to enter the bloodstream directly and therefore are generally emptied into the bloodstream only after passing through the lymphatic system.

digestion absorption

Most of the ______________and______________ of food occurs in the small intestine.

digestion and absorption

No _____________ or ____________ occurs in the esophagus; it serves merely to transport food from the mouth to the stomach.

digestion or absorption

The health of the cells is further enhanced by various hormones and other substances that participate in or are produced as part of the ____________ _________.

digestive process

continual waves of muscle contractions, followed by muscle relaxation, force the food along the _______________ _______from the esophagus onward

digestive tract

In the near future, the accessibility of genetic information will enhance the ability of health professionals to personalize nutrition recommendations that can optimize nutritional status and improve the outcomes of nutrition-related __________.

diseases

Studies of families, including those with twins and adopted children, provide strong support for the effects of genetics in various _____________. In fact, family history is considered to be an important risk factor in the development of many nutrition-related ____________.

disorders diseases

Genetic discoveries are leading to new___________that disrupt disease processes at the molecular level and to tests that predict our risk for disease.

drugs

The three parts of the small intestine are

duodenum (first 10 inches), the jejunum (second 4 feet), and the ileum (last 5 feet).

The human body must maintain reserves of nutrients; otherwise, we would need to _______ ________________.

eat continuously

Neurons respond to ___________ and _____________ signals, conduct electrical impulses, and release chemical regulators.

electrical and chemical

The presence of feces in the rectum stimulates ______________.

elimination

An organelle composed of a network of canals running through the cytoplasm. Part of the ER contains ribosomes.

endoplasmic reticulum (ER)

A continual recycling of compounds such as bile acids between the small intestine and the liver

enterohepatic circulation

A compound that speeds the rate of a chemical reaction but is not altered by the reaction these all are proteins (some are made of genetic material).

enzyme

__________ are a key part of digestion. Each is specific to one type of chemical process.

enzyme

Changes in gene function that are independent of DNA sequence. For example, malnutrition during pregnancy may modify gene expression in the fetus and affect long-term body weight regulation in the offspring.

epigenetics

The way that the genome is marked and packaged inside the cell nucleus.

epigenome

The flap that folds down over the trachea during swallowing.

epiglottis

A hormone released by the adrenal glands (located on each kidney) and various nerve endings in the body. It acts to increase glycogen breakdown in the liver, among other functions.

epinephrine

The hormones .........................have just the opposite effect on blood glucose. They all cause an increase in blood glucose through a variety of actions.

epinephrine, norepinephrine, glucagon, and growth hormone

The surface cells that line the outside of the body and all external passages within it.

epithelial tissue

Humans are composed of four primary types of tissue:

epithelial, connective, muscle, and nervous.

A hormone secreted mostly by the kidneys that enhances red blood cell synthesis and stimulates red blood cell release from bone marrow.

erythropoietin

A tube in the GI tract that connects the pharynx with the stomach.

esophagus

Capillaries service _________ __________of the body via individual capillary beds that are only one cell layer thick.

every region

The body has many receptors that receive information about what is happening within the body and in the outside environment. For the most part, these receptors are found in our _____________________________. We act on information from these receptors via the nervous system.

eyes, ears, skin, nose, and stomach

Some compounds require a carrier protein to follow a concentration gradient into absorptive cells. This type of absorption is called faciliated diffusion. Fructose is one example of a compound that makes use of such a carrier to allow for this.

facilitated diffusion

Merely eating food will nourish you. (T/F)

false

This signal is induced by the presence of_______in the small intestine. Bile is released and delivered to the duodenum via a tube called the bile duct

fat

Mass of water, fiber, tough connective tissues, bacterial cells, and sloughed intestinal cells that passes through the large intestine and is excreted through the anus

feces

The turnover of many cells of the immune system is quite rapid—only a __________ or_________. The constant resynthesis of cells requires steady nutrient intake.

few hours or days

When the contents of the small intestine enter the large intestine, the material left bears little resemblance to the ...............

food originally eaten

An organ attached to the underside of the liver; site of bile storage, concentration, and eventual secretion.

gallbladder

The bile is stored and concentrated in the _______________ until the ______________ receives a hormonal signal to release the bile.

gallbladder

The main sites in the body used for digestion and absorption of nutrients. It consists of the mouth, esophagus, stomach, small intestine, large intestine, rectum, and anus.

gastrointestinal (GI) tract

Once nutrients and other dietary components are taken up by cells, they may interact with our genes and have an effect on _________ ____________.

gene expression

Use of DNA information on a gene to produce a protein. Thought to be a major determination of cell development.

gene expression

There is strong evidence that cardiovascular disease is the result of _______-___________interactions. As discussed in Chapter 1, elevated __________ ______________ is one major risk factor for development of cardiovascular disease.

gene-environment blood cholesterol

Each new DNA contains one new strand of DNA and one strand from the original DNA. In this way, the genetic code is preserved from one cell __________ to the next.

generation

A specific segment on a chromosome and provide the blueprints for the production of all body proteins.

genes

Chromosomes contain several ________ made up of __________________ _____________.

genes deoxyribonucleic acid (DNA).

Both of the two common types of diabetes—type 1 and type 2—have ____________ ________. Evidence for these genetic links comes from studies of families, including twins, and from the high incidence of diabetes among certain population groups

genetic links

The blood maintains a small reserve of _________ and ____________ ____________.

glucose and amino acids.

Large dosages of other nutrients frequently found in supplements, such as vitamin A and iron, can cause ___________ _______ _________because they are not readily excreted.

harmful side effects

The portion of the circulatory system that uses a large vein (portal vein) to carry nutrient-rich blood from capillaries in the intestines and portions of the stomach to the liver.

hepatic portal circulation

Large vein leaving the intestine and stomach and connecting to the liver.

hepatic portal vein

This rapid cell turnover leads to ______ nutrient needs for the small intestine. Fortunately, many of the old cells can be _________ ________ and have their component parts reused.

high broken down

When people do not meet certain nutrient needs, these nutrients are obtained by breaking down a tissue that contains..............

high concentrations of the nutrient.

Another genetic variation can cause abnormally high levels of an amino acid called _______________, which increases cardiovascular disease risk.

homocysteine

The term ____________ comes from the Greek word for "to stir or excite."

hormone

common concept in nutrition is that nurture—....................—to be expressed.

how people live and the environmental factors that influence them—allows nature—each person's genetic potential

Peroxisomes get their name from the fact that _______________ _____________ is formed as a result of such enzyme action.

hydrogen peroxide (H2O2)

The tongue, through the use of its taste buds, ...................

identifies foods on the basis of their specific flavor(s).

If the body's nonspecific immune defenses are unable to block a microorganism's entry into the bloodstream, cells and chemicals involved in specific (or adaptive) immunity will_________ and ___________the invading pathogen.

identify and destroy

The ring of smooth muscle between the end of the small intestine and the beginning of the large intestine.

ileocecal sphincter

The mechanical and chemical digestion begins..........

in the mouth

In developing nations, where food shortages are common, malnutrition increases susceptibility to___________ ____________, such as diarrheal disease.

infectious diseases

The pancreas has both endocrine and digestive functions. As a gland of the endocrine system, the pancreas manufactures hormones—_________ and _____________—that are secreted into the blood to regulate blood glucose levels

insulin and glucagon

The anus contains two anal sphincters

internal and external

Research has shown that _____________ ___________play a significant role in the maintenance of health, especially health of the colon. It is speculated that higher levels of beneficial organisms can reduce the activity of disease-causing bacteria.

intestinal bacteria

A proteinlike compound produced by the stomach that enhances vitamin B-12 absorption in the ileum.

intrinsic factor

The main function of the _____________ is to remove waste from the body. They constantly filtering blood to control its composition. This results in the formation of urine,

kidneys

The organs that make up the GI tract, as well as some additional accessory organs located nearby, are collectively .........

known as the digestive system.

As food moves along the GI tract, nutrients are absorbed and the waste products reach the____________ ______________.

large intestine

if the small intestine were coated with mucus, digestion and absorption would be very ___________. Therefore, the pancreas and intestinal cells secrete bicarbonate to neutralize the acid.

limited

Fat-digesting enzyme produced by the salivary glands, stomach, and pancreas.

lipase

Many vitamins and minerals are stored in the _________, whereas other nutrient stores are found in other sites in the body.

liver

The ________ produces a substance called bile.

liver

A circular muscle that constricts the opening of the esophagus to the stomach.

lower esophageal sphincter

The cells of the esophagus secrete mucus to ___________the passage of food, but no digestive enzymes are produced.

lubricate

The hollow opening inside a tube, such as the GI tract

lumen

Most fats are absorbed into the _________ _________, which eventually empty into the bloodstream

lymph vessels

A cellular organelle that contains digestive enzymes for use inside the cell for turnover of cell parts. (suicide bags)

lysosome

In the digestive system, food is broken down ___________ and ________________.

mechanically and chemically.

Diet changes can help these people, but______________and even __________ are needed to address these problems

medications and even surgery

Two common features in all cells

membranes and organelles (15 different kinds)

Refers to the entire collection of chemical processes involved in maintaining life.

metabolism

endocrine system plays a major role in the regulation of .................................... and subsequently releasing them into the blood

metabolism, reproduction, water balance, and many other functions by producing hormones in the endocrine glands of the body

The skin and the intestinal cells support the immune system by forming an important barrier against invading ____________. If the integrity of either one of these barriers is compromised, microorganisms can invade the body and cause ___________. Substances secreted by the skin and intestinal cells can also destroy pathogens.

microorganisms illness

Extensive folds on the muscosal surface of the absorptive cells.

microvilli

Bacteria in the large intestine are able to break down some of the remaining food products that enter the large intestine, such as the ................... Some of the products of bacterial metabolism in the large intestine, which include various fatty acids and gases, can then be absorbed.

milk sugar lactose (in lactose intolerant people), and some components of fiber

The processes of digestion and absorption take place in a long tube that is open at both ends and extends from the __________ to the __________.

mouth to the anus

The information stored on the DNA in the nucleus is copied onto RNA through the process of transcription and then ................

moves out to the cytoplasm through pores in the nuclear membrane.

The lining of the small intestine is called the

mucosa

A thick fluid secreted by many cells throughout the body. It contains a compound that has both carbohydrate and protein parts. It acts as a lubricant and means of protection for cells.

mucus

Unlike the small intestine, the large intestine has a number of ____________-producing cells. The_________secreted by these cells functions to hold the feces together and protect the large intestine from the bacterial activity within it.

mucus

Insulin allows for the movement of glucose from the blood into ..................

muscle and adipose cells

Short-term storage of carbohydrate occurs in ____________ and _____________ in the form of glycogen.

muscle and liver

The lymphatic system does not have a pump its flow is driven by ..................................

muscle contractions arising from normal body movements.

The feces or stool remains in the last portion of the large intestine, the rectum, until ______________ ______________push it into the anus to be eliminated.

muscular movements

Still, although some individuals may be genetically predisposed to store body fat, whether they do so depends on how many calories they consume relative to their ___________.

needs

At the top of the esophagus,________ _______release signals to tell the GI tract that food has been consumed.

nerve fibers

The body system consisting of the brain, spinal cord, nerves, and sensory receptors. This system detects sensations, directs movements, and controls physiological and intellectual functions.

nervous system

The structural and functional unit of the nervous system. Consists of a cell body, dendrites, and an axon.

neuron

Defenses that stop the invasion of pathogens; requires no previous encounter with a pathogen

nonspecific immunity

A neurotransmitter from nerve endings and a hormone from the adrenal gland. It is released in times of stress and is involved in hunger regulation, blood glucose regulation, and other body processes.

norepinephrine

A genetic variation can directly affect the proteins encoded by our genes and result in different:

nutrient requirements among individuals. •susceptibilities to diseases. •effects of environmental factors (such as our diet) on our genes and the proteins they make.

You must first digest the food by breaking it down into usable forms of the essential _______ that can be absorbed into the bloodstream. Once __________ are taken up by the bloodstream, they can be distributed to and used by body cells.

nutrients

Study of the effects of genes on nutritional health, such as variations in nutrient requirements and responsiveness to dietary modifications.

nutrigenetics

Study of how food impacts health through its interaction with our genes and its subsequent effect on gene expression.

nutrigenomics

Study of interactions between nutrition and genetics

nutritional genomics

The everyday function of the human body relies on the coordination of many highly structured __________systems

organ

A collection of organs that work together to perform an overall function. Example is digestion system

organ system

The cardiovascular system facilitates the exchange of ............................. between the body's internal and external environments.

oxygen, nutrients, and wastes

A measure of relative acidity or alkalinity of a solution. The ____ scale is 0 to 14. A_____of 7 is neutral; a _____ below 7 is acidic; and a _____ above 7 is alkaline.

pH

The ____________ and __________ ___________produce most of the digestive enzymes; however, the mouth and the stomach also contribute their own enzymes to the process of digestion

pancreas and small intestine

When the nutrient concentration is higher in the lumen of the small intestine than in the absorptive cells, the difference in nutrient concentration drives the nutrient into the absorptive cells by diffusion. Fats, water, and some minerals are examples of nutrients that move down a concentration gradient to be absorbed

passive diffusion

The small intestine absorbs nutrients through the intestinal wall through various means and processes

passive diffusion, facilitated diffusion, active absorption, Phagocytosis and pinocytosis

A coordinated muscular contraction used to propel food down the GI tract.

peristalsis

A cell organelle that destroys toxic products within the cell.

peroxisome

Process in which a cell forms an indentation, and particles or fluids enter the indentation and are engulfed by the cell.

phagocytosis

The organ of the digestive tract and respiratory tract located at the back of the oral and nasal cavities, commonly known as the throat.

pharynx

Any of a class of fat-related substances that contain phosphorus, fatty acids, and a nitrogen-containing base. These are an essential part of every cell.

phospholipids

We are born with some aspects of immune function, such as ...................

physical and chemical barriers against infection, the inflammatory response, and the ability of some white blood cells to engulf microorganisms by phagocytosis.

Substance that stimulates bacterial growth in the large intestines. Ex:fructooligosaccharides

prebiotic

The main function of sphincters is to ............

prevent the backflow of GI tract contents

Product that contains specific types of bacteria. Use is intended to colonize the large intestine with the specific bacteria in the product. An example is yogurt.

probiotic

few types of cancer (e.g., some forms of colon and breast cancer) have a strong genetic link, and genetics may play a role in others, such as ____________ ___________.

prostate cancer

Nutrients that are important for the health of the immune system include................

protein, essential fatty acids, iron, copper, zinc, vitamins A, C, and D, and some B vitamins.

The products (________) of all the recipes in the cookbook (_____ ___________ ________) would then make up the human organism.

proteins the human genome

Ring of smooth muscle between stomach and small intestine.

pyloric sphincter

A site in a cell at which compounds (such as hormones) bind. Cells that contain ________ for a specific compound are partially controlled by that compound.

receptor

Terminal portion of the large intestine.

rectum

Stomach size varies individually and can be ___________ _____________ as a radical treatment for obesity

reduced surgically

Metabolism and other biochemical reactions take place in the cell cytoplasm and organelles and They enable us to ................

release and use energy from foods, synthesize one substance from another, and prepare waste products for excretion.

The single-stranded nucleic acid involved in the transcription of genetic information and translation of that information into protein structure.

ribonucleic acid (RNA)

Cytoplasmic particles that mediate the linking together of amino acids to form proteins; may exist freely in the cytoplasm or attached to endoplasmic reticulum.

ribosomes

Blood travels two basic routes. In the first route, blood circulates from the_________side of the heart, through the lungs, and then back to the heart. In the lungs, blood picks up oxygen and releases carbon dioxide. After this exchange of gases has taken place, blood is said to be oxygenated and returns to the left side of your heart.

right

Watery fluid, produced by the salivary glands in the mouth, that contains lubricants, enzymes, and other substances.

saliva

The binding of hormones activates additional compounds called _________ ____________within the cell to carry out the assigned task. This is true of insulin. A few hormones can penetrate the cell membrane and eventually bind to receptors on the DNA in the nucleus

second messengers

Membrane-bound vesicles produced by the Golgi complex; contain protein and other compounds to be secreted by the cell.

secretory vesicles

The mouth performs many functions in the digestion of food. Besides chewing food to reduce it to smaller particles, the mouth also ............

senses the taste of the foods we consume.

The neurotransmitters used in this process are often made from common nutrients found in foods, such as amino acids. The amino acid tryptophan is converted to the neurotransmitter _________, and the amino acid tyrosine is converted to the neurotransmitters norepinephrine and epinephrine (also called adrenaline).

serotonin

Almost all of the functions involved in digestion and absorption are controlled by.............. Many common ailments arise from problems with the digestive system.

signals from the nervous system, hormones from the endocrine system, and hormonelike compounds

Sphincters respond to various stimuli, such as .............

signals from the nervous system, hormones, acidic versus alkaline conditions, and pressure that builds up around the sphincter.

The taste of food, or the anticipation of it, ....................... to prepare for the digestion of food

signals the rest of the GI tract

the nervous system receives information through stimulation of various receptors, processes this information, and sends out ............

signals through its various branches for an action that needs to be taken

Cells throughout the body—______ and ____________ cells—work in concert with the cells and tissues of the immune system to defend the body against infection.

skin and intestinal cells

The_________ _____________is considered "small" because of its narrow (1 inch [2.5 centimeters]) diameter. It is actually quite long—about 10 feet (3 meters), beginning at the stomach and extending to the large intestine

small intestine

transmission of the signal occurs through a change in the concentration of two nutrients, _____________ and ___________, in the neuron.

sodium and potassium

There is very little absorption of nutrients from the stomach, except for____________ and ___________.

some water and alcohol

Function of white blood cells directed at specific antigens

specific immunity

The esophagus is a long tube that connects the pharynx with the____________.

stomach

a large sac that can hold up to 4 cups (or 1 quart) of food for several hours until all of the food is able to enter the small intestine

stomach

During_____________, food lands on the epiglottis, folding it down to cover the opening of the trachea. ________________also stops automatically.

swallowing breathing

The space between one neuron and another neuron (or cell).

synapse

chyme, which slowly leaves the stomach a _______________ at a time and enters the small intestine.

teaspoon (5 milliliters)

The acid in the gastric juice destroys _____ _______________ __________of proteins, converts inactive digestive enzymes to their active form, partially digests food protein, and makes dietary minerals soluble so that they can be absorbed.

the biological activity

The nose and our sense of smell greatly contribute to our ability to sense _____________food. When we have a cold and our noses are stuffed up and congested, even our favorite foods will not taste as good as they normally do.

the taste of

Collections of cells adapted to perform a specific function.

tissues

Near the pharynx is a flap of tissue (called the epiglottis) that prevents the bolus of swallowed food from entering the _____________.

trachea (wind pipe)

Process by which genetic information stored as DNA within the nucleus is copied to RNA during protein synthesis.

transcription

Endoplasmic reticulum contains the ribosomes, where the RNA code is ......................Many of these proteins play a central role in human nutrition.

translated into proteins during protein synthesis.

Process by which genetic information copied onto RNA dictates the amino acid sequence to form a protein.

translation

(t/f) The physical structure of the small intestine is very important to the body's ability to digest and absorb the nutrients it needs.

true

The remnants of a meal also contain some minerals and some fiber. Because water is removed from the large intestine, its contents become semisolid by the time they have passed through the first __________-_______of it.

two-thirds

A brothy, meaty, savory flavor in some foods. Monosodium glutamate enhances this flavor when added to foods.

umami

Nitrogenous waste product of protein metabolism; major source of nitrogen in the urine, chemically.

urea

Tube that transports urine from the kidney to the urinary bladder.

ureter

Tube that transports urine from the urinary bladder to the outside of the body.

urethra

The body system consisting of the kidneys, urinary bladder, and the ducts that carry urine. This system removes waste products from the circulatory system and regulates blood acid-base balance, overall chemical balance, and water balance in the body.

urinary system

A blood vessel that carries blood to the heart.

vein

The fingerlike protrusions into the small intestine that participate in digestion and absorption of food.

villi

large intestine differs from the small intestine in that there are no _______or___________ ____________. The absence of villi means that little absorption takes place in the large intestine in comparison to the small intestine.

villi or digestive enzymes

The bacteria that live in the large intestine produce some ______________ that can be absorbed.

vitamins (vitamin K and biotin)

The final role of the digestive system is elimination of _________.

wastes

Components of the bile enable large portions of fat to break into smaller bits so that they can be suspended in _________

water

While in the stomach, the food is mixed with gastric juice, which contains................

water, hydrochloric acid, and enzymes.

Nutrients absorbed from the large intestine include

water, some vitamins, some fatty acids, and the minerals sodium and potassium.

Cell membrane is a lipid bilayer (or double membrane) of phospholipids with their______________ _____________ heads facing both the interior of the cell and the exterior of the cell. Their ______________ _____________ tails are tucked into the interior of the cell membrane.

water-soluble