Chapter 3-Body Basics and Digestion

State the 3 Requirements for a healthy cardiovascular and lymphatic circulatory systems

1. Drinking sufficient water to replace the water lost each day 2. Cardiovascular fitness-nutrition and physical activity *Healthy red blood cells are constantly manufactured and require many essential nutrients 3. The blood is very sensitive to malnutrition that can be caused by dietary deficiencies or imbalance of vitamins and minerals

List in order of the components of the digestive tract

1. Mouth 2. Esophagus 3. Stomach 4. Small Intestine 5. Large Intestine -Rectum -Anus

Fight or Flight reaction/Stress Response and the body response by the: 1. Nerves 2. Hormonal Systems 3. Metabolism 4. Digestive System 5. Liver 6. Fat Cells

1. Nerves: Release Neurotransmitters 2. Hormonal System: Glands release epinephrine (adrenaline) and norepinephrine 3. Metabolism: Speeds up 4. Digestive System: Shuts down 5. Liver: Pours forth glucose from its stores for energy (muscle) 6. Fat Cells: Release Fat

Describe secretions the digestive system (Secretion, Organ and Role)

1. Saliva: Mouth, Starch and Fat digesting enzymes 2. Gastric Juice: Stomach, A mix of water, enzymes, and HCL (HCL activates the protein digesting enzyme) 3. Bile: Produced in the Liver, Stored in the Gallbladder, and Released into the Small Intestine as an emulsifier: Disperses Fat and Oils in the watery liquids getting it ready for enzymes 4. Pancreatic Juice: Released into the Small Intestine, Produced in the Pancreas, contains alkaline compound bicarbonate to Neutralize Stomach Acid

Bile

A cholesterol containing digestive fluid made by the liver, stored in the gallbladder, and released into the small intestine when needed It emulsifies fats and oils to ready them for enzymatic digestion

Sphincter/Valve

A circular muscle surrounding and able to close a body opening EX: Cardiac Sphincter at the base of the esophagus where it meets the stomach Pyloric Valve regulates the flow of the chyme from the stomach to the small intestine

Digestive Tract

A flexible, muscular tube that digests food and absorbs its nutrients and some non nutrients

Insulin

A hormone from the pancreas that helps glucose enter cells from the blood

Glucagon

A hormone from the pancreas that stimulates the liver to release glucose into the blood stream

Probiotic

A live microorganism which, when administered in adequate amounts, alters the bacterial colonies of the body in ways believed to confer a health benefit EX: Yogurt

Mucus

A slippery coating of the digestive tract lining (and other body linings) that protects the cells from exposure to digestive juices (and other destructive agents) Mucous Membrane

Bolus

A small rounded mass of chewed food prepared for swallowing

Prebiotic

A substance that may not be digestible by the host, such as FIBER, but that serves as food for probiotic bacteria and thus promotes their growth

Cytoplasm

A thick solution that fills each cell and is enclosed by the cell membrane. In eukaryotic cells, the cytoplasm includes all material inside the cell and outside the nucleus

Main Digestive Function of the Stomach

Adds Acids, Enzymes, and Fluid Churns, mixes and grinds food into a liquid mass (Chyme) Peristalsis

Digestive System

After you have eaten, your brain directs the many organs of the digestive system to digest and absorb the complex mixture of chewed and swallowed food (Chyme) The digestive tract and alimentary canal are names for the tubular organs that extend from mouth to anus The whole system including the pancreas, liver, and gallbladder=Gastrointestinal or GI system Mechanical and Chemical Digestion

Pancreas

An organ with 2 main functions 1. An Endocrine Function: the making of hormones such as insulin, which it releases directly into the blood stream 2. An Exocrine Function: The making of digestive enzymes which it releases through a duct into the small intestine to assist with digestion

Mitochondria

An organelle found in large numbers in most cells, in which biochemical processes of respiration and energy production occur

Enzyme

Any of a great number of working proteins that speed up a specific chemical reaction without changing themselves. EX: Breaking the bonds of a nutrient

Gallbladder

Attached to the liver and stores bile until it is needed for digestion

Chemical digestion

Begins in the mouth where food is mixed with an enzyme in the saliva that acts on starch and some fat Digestion continues in the stomach where stomach acids and enzymes break down protein Digestive processes in the small intestine continue where the liver and gallbladder contribute the bile to emulsify fat, and the pancreas and small intestine donate enzyme that break down food to nutrients Bacteria in the colon break down certain fibers

Artery

Blood vessels that carry blood containing fresh oxygen from the Heart to the Tissues

Veins

Blood vessels that carry blood, with the carbon dioxide is has collected, from the tissues back to the heart

Excretory System

Cells generate a number of wastes and all of them must be eliminated. Many of the body's organs play roles in removing wastes The kidneys adjust the blood's composition in response to the body's needs, disposing of everyday wastes and removing toxins

Storage Systems

Cells need Nutrients around the clock. Providing the cells with a constant flow of the needed nutrients requires the cooperation of many body systems. These systems store/release nutrients to meet the cells needs btw meals Among the major storage sites are the Liver and Muscles which store carbs, and the Fat cells storing Fat

Hormones

Chemicals that are secreted by glands into the blood in response to conditions in the body that require regulation. These chemicals serve as messengers, acting on other organs to maintain constant conditions

Mechanical Digestion

Chewing mashes up the food in the mouth The stomach and intestines liquify food through mashing and squeezing actions Fluid is added to the bolus in the mouth, stomach and intestines

Main Digestive Function of the Mouth

Chews and mixes food with saliva to form bolus *Saliva: Coats food, Starch/Fat digesting enzymes

Bile Duct

Conducts bile to the small intestine from the Gallbaldder

Organs

Discrete structural units made of tissues that perform specific jobs EX: Heart, Liver, Brain

Nuclear Membrane

Double lipid binary membrane which surrounds the genetic material and nucleolus in eukaryotic cells

Villi

Finger like projections of the sheets of cells lining the digestive tracts The villi make the surface area much larger than it would be otherwise Singular=Villus

Mass Movement

Forcible peristaltic movements of short duration, occurring only 3 or 4 times a day, which move the contents of the large intestine from one division to the next EX: from the ascending to the transverse colon

Anus

Holds rectum closed Opens to allow elimination

Hormonal System

Hormones are secreted and released directly into the blood by glands Each gland monitors a condition and produces one or more hormones to regulate it. Each hormone acts as a messenger that stimulates growth Fasting, Feeding, and Exercise alter Hormones and Balance EX: Pancreas releases Insulin (removes glucose from blood)

Identify the 3 organs and general processes involved in excretion of wastes

Lungs: Carbon dioxide travels in the blood to the lungs where it is exchanged for oxygen Liver: Other wastes are pulled out of the blood by the liver. The liver processes wastes and either tosses them into the digestive tract with bile (disposed of in feces) or prepares them to be sent to the kidneys for disposal in urine Kidneys: Straddle the Cardiovascular system and filter the passing blood. *Waste and Water Removal Specialists.* Waste materials dissolved in water are collected by the nephrons. The wastes become concentrated as urine and travels to the urinary bladder Bladder: The bladder collects urine continuously and empties periodically, removing waste from the body

Immune System

Many of the body's tissues cooperate to maintain defenses against infection, and all these tissues depend on ample supply of nutrients to function properly EX: the skin acts as a physical barrier, and the body's cavities are lined by membranes that resist microbes *These membranes are highly sensitive to vitamin and other nutrient deficiencies

Chewing

Mastication; the FIRST step in mechanical digestion where solid food pieces are torn into shreds that can be swallowed without choking

Basics of Digestion for Fat

Mouth: A small amount of fat (especially milk fat) is digested by a fat digesting saliva enzyme Stomach: Fat tends to rise from the watery stomach fluid and foods and floats on top of the mixture. Only a small amount of fat is digested and fat is the last to leave the stomach Small Intestine: The liver secretes bile; the gallbladder stores it and releases it into the small intestine. Bile Emulsifies the fat and readies it for enzyme action. The pancreas produces fat digesting enzymes and releases them into the small intestine to split fats into their component parts (Fatty Acids). Small Fatty Acids are absorbed into the blood stream, but longer fatty acid chains are form chylomicrons and travel through lymph, to blood, to the liver. Large Intestine: Some fatty materials escape absorption are are carried out of the body with other wastes

Basics of Digestion for protein

Mouth: Chewing crushes and softens protein rich foods and mixes them with saliva Stomach: Stomach acid (HCL) works to uncoil protein strands and to activate the stomach's protein digesting enzyme. Then the enzyme breaks the protein strand into smaller fragments Small Intestine: Enzymes of the small intestine and pancreas split protein fragments into smaller ones or amino acids. Enzymes on the cells of the intestinal wall break some protein fragments into free amino acids and both are absorbed Large Intestine: Carries undigested protein residue out of the body (almost all is digested)

Basics of Digestion for Carbohydrates (Starch and Sugars)

Mouth: Saliva moistens and lubricates food; chewing crushes and mixes it with a salivary enzyme that initiates starch digestion Stomach: Digestion continues in the upper storage areas and stops once it gets into the stomach where the salivary enzyme (protein) is destroyed by HCL Small intestine: Digestion continues by a strong starch digesting enzyme produced by the pancreas. Cells in the intestinal lining have enzymes on their surface that break down sugar and starch fragments into simple sugars which are then absorbed Large Intestine: Undigested carbs (Fiber) are partly broken down by intestinal bacteria

Segmentation

Muscular contractions (circular) that mash up food (NOT MOVE IT) Often occur in the small intestine

Recall how nutrients are transported in the body

Nutrients are absorbed through cells lining the intestines (villi) and deposit the water soluble compounds in the blood, and the fat soluble ones lymph. Blood and lymph vessels transport nutrients to the body cells. Lymph vessels initially transport most of the products of fat digestion and the fat soluble vitamins to a large blood vessel near the heart. The blood vessels directly transport the products of carb and protein digestion, most vitamins and the minerals from the digestive tract to the liver.

Main Digestive Function of the Esophagus

Passes food to Stomach

Main Digestive Functions of the Large Intestine (colon)

Reabsorbs water and minerals Passes waste (fiber, bacteria, any unabsorbed nutrients) and some water to rectum

Nervous System

Receives and integrates info from sensory receptors all over the body Hunger regulation and fight or flight response is controlled by the Hormonal and Nervous Systems Sensations of hunger and appetite are perceived by the brains cortex Hypothalamus monitors many body conditions including Availability of Nutrients and Water and Metabolism The digestive tract signals hunger to the brain by way of Hormones and Nerves

Ribosome

Responsible for protein production in all living cells

Main Digestive Functions of the Small Intestine

Secretes enzymes that digest carbs, fats, and protein Bile Duct: Conducts bile from gall bladder (made in liver) to the small intestine Pancreatic Duct: Conducts pancreatic juices Cells lining the small intestine absorb nutrients into blood and lymph

Saliva

Softens rough or sharp foods to prevent them from harming the esophagus Also moistens and coats each bite of food making it slippery Aids in chemical digestion (Starch and small amount of fat digestion)

Rectum

Stores waste prior to elimination

Kidneys

Straddle the cardiovascular system and filter the passing blood. Waste materials, dissolved in water, are collected by the kidneys working units, nephrons Waste becomes concentrated as urine and exits to the urinary bladder Excretory system function too

Tissues

Systems of cells working together to perform specialized tasks EX: Muscles, Nerves, Blood, and Bone

Basic Tastes

Taste buds contain surface structures that can detect 5 basic chemical tastes from the Amino Acids in foods 1. Sweet 2. Sour 3. Bitter 4. Salty 5. Umami ("Savory" in Japanese)

Identify the two organs involved in storage of carbohydrate and the type of tissue that stores fat within the body

The body stores limited amounts of carbs as glycogen in muscle and liver cells. Muscle cells reserve their glycogen for their own use and if no food is available the livers glycogen supply dwindles quickly Adipose tissue stores fat in fat cells

Circulatory and Lymphatic Systems

The body's circulating fluids are the blood and lymph Circulatory System=Cardiovascular+Lymphatic Distributes Nutrients and Removes Waste

Adipose

The body's fat tissue, consisting of masses of fat-storing cells and blood vessels to nourish them

Plasma

The cell free fluid part of blood and lymph

Nucleus

The central and most important dense organelle present in most eukaryotic cells, typically a structure bound by a double membrane, containing the genetic material

Gastric Juices

The digestive secretion of the stomach

Blood

The fluid of the cardiovascular system Composed of water, red and white blood cells, other formed particles, nutrients, oxygen, and other constituents

Chyme

The fluid resulting from the actions the stomach upon a meal

Lymph

The fluid that moves from the blood stream into tissue spaces and then travels into its own vessels which eventually drain back into the bloodstream Carries Fat

Cell Membrane

The semipermeable membrane surrounding the cytoplasm of a cell

Describe the process of regulation of hunger by the brain

The sensations of hunger and appetite are perceived by the brain's cortex (thinking outer layer). Deep inside the brain, the Hypothalamus monitors conditions like metabolism and the availability of nutrients and water To signal hunger, the digestive tract sends messages to the hypothalamus through hormones and nerves making you want to eat. The conscious brain (Cortex) can override signals and make you not eat when you're hungry or eat when you are not hungry

Cell

The smallest unit in which independent life can exist All living things are single cell organisms or organisms made of cells

Stomach Muscles

The stomach is an elastic, pouch like muscular organ of the digestive tract that grinds and churns swallowed food and mixes it with acid and enzymes forming chyme

Glycogen

The storage form of carbohydrate energy (glucose) in animals

Peristalisis

The wavelike muscular squeezing of the esophagus, stomach, and small intestine that pushes their contents along Circular and Longitudinal Muscle layer contractions