Food and Nutrition Chapter 4
Process by which substances are taken up from the GI tract and enter the bloodstream or the lymph
Absorption
The teeth, tongue, salivary glands, liver, gallbladder, and pancreas are _____ of the digestive system that assist the GI tract in food digestion, nutrient absorption and distribution, and waste elimination.
Accessory organs
Substances that donate hydrogen ions
Acids
_____ are substances that lose H+ when dissolved in water; _____ are substances that remove and accept H+ when dissolved in water
Acids, bases
The normal pH of blood is slightly
Alkaline
_____ is a group of organ that work together for a similar purpose. The urinary system, for example, includes the kidneys and the bladder
An organ system
Scientific study of cells and other body structures
Anatomy
Vessels that carry blood away from the heart
Arteries (動脈)
Substances that accept hydrogen ions
Bases
Substance that is produced by the liver to prepare fat and fat-soluble vitamins for digestion and absorption
Bile
Extent to which the digestive tract absorbs a nutrient and how well the body uses it
Bioavailability
Plasma, red blood cells, and white blood cells are components of
Blood
Smallest blood vessels
Capillaries
The _____ system is an example of an organ system
Cardiovascular
Two systems responsible for circulating fluids through the body
Cardiovascular system, lymphatic system
Humans are a mixture of chemicals which are organized into
Cells
Attraction that holds atoms together
Chemical bond
Process that change the atomic arrangements or molecules
Chemical reactions
Particles formed by small intestinal cells that transports lipids in the bloodstream
Chylomicron
Mixture of gastric juice and partially digested food
Chyme
Molecules that contain two or more different elements in specific proportions
Compounds
Molecule that contains coded instructions for synthesizing proteins
DNA
Process by which large food molecules are mechanically and chemically broken down
Digestion
The primary roles of the _____ system are the breakdown of large food molecules into smaller components (nutrients) and the absorption of nutrients into the bloodstream or lymphatic system.
Digestive
The mouth, esophagus, stomach, and small and large intestines are the major structures of the
Digestive system
Bicarbonate secreted here
Duodenum
First segment of the small intestine
Duodenum
The small intestine has three sections
Duodenum, jejunum, ileum
Ions of minerals that conduct electricity when they are dissolved in water
Electrolytes
Small, negatively charged particles that surround the nucleus of an atom
Electrons(電子)
Each type of atom; substance that cannot be separated into simpler substances by ordinary chemical or physical means
Element
_____ is comprised of organs and tissues, including the thyroid gland and pancreas that produce a variety of chemical messengers called hormones.
Endocrine System
An _____ is a molecule (usually a protein) that catalyzes (speeds up) a particular chemical reaction.
Enzyme
Molecule (usually a protein) that speeds up a particular chemical reaction
Enzyme
_____ are recyclable; they do not become part of the products of a reaction, as a result, one _____ molecule can catalyze many reactions
Enzyme
Flap of tissue that folds down over the windpipe to keep food from entering the respiratory system during swallowing
Epiglottis
The _____ is a flap of tissue that prevents food from entering the larynx and trachea during food consumption
Epiglottis
Tubular structure of the GI tract that connects the pharynx with the stomach
Esophagus
Condition that can result when acid reflux damages the wall of the lower esophagus and causes ulcers
Gastro esophageal reflux disease (GERD)
Muscular tube that extends from the mouth to the anus
Gastrointestinal tract
Chemical symbol for hydrogen ion
H+
Backflow of irritating stomach contents into the esophagus
Heartburn
If the gastroesophageal sphincter does not function properly and relaxes while food is still in the stomach, reflux, the backflow of irritating stomach contents into the esophagus, can occur and cause
Heartburn
Maintenance of an internal chemical and physical environment that is critical for good health and survival
Homeostasis
_____ is the relatively constant internal environment in the body that is critical for good health and survival
Homeostasis
When released into the bloodstream, a _____ conveys information to cells that are specially equipped to respond (target cells)
Hormones
_____ regulate a variety of physiological activities, including metabolism, digestion, maintenance of fluid balance, and the maturation of reproductive organs that occurs during puberty
Hormones
Last segment of the small intestine
Ileum
The villi facilitate absorption of nutrients in the small intestine by
Increasing the surface area
Hair, nails, and skin, the largest organ of your body, are structures of the _____
Integumentary System
What can metabolize food, make vitamins K and biotin, and produce substances that the colon can use for energy
Intestinal bacteria
Atom or group of atoms that has a positive or negative charge
Ion
Middle segment of the small intestine
Jejunum
Most digestion and absorption occurs here
Jejunum
Lymph vessel in villus that absorbs most lipids
Lacteal
The _____ intestine doesn't have villi
Large
Minimal absorption occurs here
Lieum
The _____ uses cholesterol to make bile
Liver
Section of esophagus next to the stomach that controls the opening to the stomach
Lower gastroesophageal sphincter
A _____ is a hollow space in an organ or structure that is surrounded by walls, such as the lumen of the small and large intestines
Lumen
Open space within a structure such as the small intestine
Lumen
_____, the primary structures of the respiratory system, enable the body to exchange gases, particularly oxygen and carbon dioxide
Lungs
Organs that work together to maintain the acid-base balance of the blood
Lungs, kidneys
Fluid in the lymphatic system
Lymph
_____ vessels empty their contents (including chylomicrons) into the cardiovascular system through a duct neat the heart
Lymphatic
Fat-soluble nutrients are absorbed into the
Lymphatic system
Elements that are found in the Earth's crust
Minerals
A typical human cell contains certain structures and various organelles, including
Mitochondria, ribosomes, and a nucleus
Matter that forms when two or more atoms interact and are held together by a chemical bond
Molecule (分子・微分子)
Fluid that lubricates and protects certain cells
Mucus
_____ is a slippery, alkaline substance that protects the stomach from its acid and digestive enzymes
Mucus
_____ are the main organs of the muscular system.
Muscles
_____ enable movement to occur, and they also provide stability for the body, Furthermore, muscles generate heat that helps maintain normal body tempratura.
Muscles
When an atom gains one electron, it has a ____ charge
Negative
The brain produces a variety of intellectual functions and emotional responses, including thoughts, memories, and emotions. The brain also controls and regulates many body functions, including hunger, muscle contractions, and physical responses to danger
Nervous System
The brain, spinal cord, and nerves throughout the rest of the body make up the
Nervous system
Identify the part of the cell responsible for genetically controlling the actions that occur in the cell
Nucleus
What is the name for the cellular structure that stores the genetic material that directs protein synthesis in the cell?
Nucleus
A human being is an _____, an organism that can digest and absorb nutrients from plants, animals, fungi, and even bacteria
Omnivore
Organism that can digest and absorb nutrients from plants, animals, fungi, and bacteria
Omnivore
Collection of tissues that function in a related fashion
Organ
Group of organs that work together for a similar purpose
Organ system
Structures in cells that have specific functions
Organelles
Two organs that produce most of the digestive enzymes
Pancreas, small intestine
Swallowing signals the GI tract that food is being eaten and stimulates _____, waves of muscular activity that help propel material through the digestive tract
Peristalsis
The contraction of muscles in the esophagus is called
Peristalsis
Type of muscular contraction of the gastrointestinal tract
Peristalsis
Scientific study of the functioning of cells and other body structures
Physiology
Positively charged particles in the nucleus(細胞核・核心) of an atom
Protons(陽子)
Lower section of the large intestine
Rectum
The main function of the _____ is to produce children
Reproductive System
_____ enables a minor amount of starch digestion to occur in the mouth
Salivary amylase
Saliva contains the enzymes _____ and _____.
Salivary amylase, lingual lipase
Substance that forms when an acid combines with a base
Salt
_____ involves ringlike muscular contractions followed by relaxation of a small region of the small intestine
Segmentation
These structures provide support, movement, and protection for the body. Additionally, bones store excesses of several minerals and produce blood cells
Skeletal System
Almost all of the macronutrients are digested and absorbed in the _____ intestine
Small
Describes a substance's ability to dissolve and form a solution
Solubility
Lesser component of a solution that dissolves in solvent
Solute
Evenly distributed mixture of two or more compounds
Solution
Primary component of a solution
Solvent
A cell is the smallest functional unit of an organism and is specialized to perform a particular function
T
Functions of the liver 1) Manufactures bile 2) Makes cholesterol
T
Functions of the lymphatic system 1) defense of the body against invading pathogens 2) Transport of absorbed dietary fats 3) Returns fluid that collects between cells back to the bloodstream
T
Segmentation differs from peristalsis in that segmentation mixes chime through a back and forth movement
T
The absorptive cells of the villus 1) move nutrients from chime into intestinal blood 2) move nutrients from chime into lacteals
T
The acidic environment of the stomach is beneficial in 1) partially digesting protein 2) killing disease causing microorganisms 3) activating some digestive enzymes
T
_____ have specialized cells that help you distinguish sweet, sour, salty, bitter, and umami tastes
Taste buds
The major components of the cardiovascular system are _____, _____, and _____.
The heart, blood, blood vessels
Bones, tendons, and ligaments are the principal organs of
The skeletal system
Cells that have similar characteristics and functions are usually joined together into large masses called
Tissues
Masses of cells that have similar characteristics and functions
Tissues
Vessels that return blood to heart
Veins
Under normal circumstances, _____ carbohydrate, protein, and fat escape digestion and absorption in the small intestine
Very little
(singular, villus) tiny, fingerlike projections of the small intestinal lining that participate in digesting and absorbing food
Villi
The main function of the gastroesphageal sphincter is to
close the opening between the esophagus and the stomach
Measure of the acidity or alkalinity of a solution
pH