STAGE 1
INTEGRATIVE
ACTIVITY BIOLOGY II Group 220
UNIVERSIDAD AUTÓNOMA DE NUEVO LEÓN
Preparatoria no. 9
Team: González Viera Natalia Daenna González Guajardo Luis Roberto Cantú Reyes Jorge Alberto Reyes Gómez Andrés Eduardo De León Ramírez Natividad Aron
Health is the level of functional and metabolic efficiency of a living organism. In humans it is the ability of individuals or communities to adapt and self-manage when facing physical, mental or social changes. There are several benefits of a healthy life. Your body becomes free from various forms of disorders and thus, you get a longer life. You can live a life without suffering from any aches, pain, or discomfort.
HEALTH IN ADOLESCENCE Adolescence represents a critical period of development during which personal lifestyle choices and behaviour patterns establish, including the choice to be physically active.
THE IMPORTANCE OF THE NUTRIMENTS’ ROLE IN THE ADOLESCENCE The phenomenal growth that occurs in adolescence, second only to that in the first year of life, creates increased demands for energy and nutrients. Total nutrient needs are higher during adolescence than any other time in the lifecycle. Nutrition and physical growth are integrally related; optimal nutrition is a requisite for achieving full growth potential. Failure to consume an adequate diet at this time can result in
delayed sexual maturation and can arrest or slow linear growth. Nutrition is also important during this time to help prevent adult diet-related chronic diseases, such as cardiovascular disease, cancer, and osteoporosis. Prior to puberty, nutrient needs are similar for boys and girls. It is during puberty that body composition and biologic changes emerge which affect genderspecific nutrient needs. Nutrient needs for both males and females increase sharply during ad olescence.1 Nutrient needs parallel the rate of growth, with the greatest nutrient demands occurring during the peak velocity of growth. At the peak of the adolescent growth spurt, the nutritional requirements may be twice as high as those of the remaining period of adolescence.
Nutrition:
The nutrients protein, carbohydrates, and fats in food serve as the body's energy sources. Calories are the measurement used to express the energy delivered by food. The body demands more calories during early adolescence than at any other time of life. Boys require an average of 2,800 calories per day. Girls require an average of 2,200 calories per day. Importance of diet: A balanced diet is one that gives your body the nutrients it needs to function correctly. In order to get the proper nutrition from your diet, you should obtain the majority of your daily calories.
Nutriments: Proteins: Of the three nutrients, we're least concerned about protein. Not because it isn't important of our body weight is made up of protein but because adolescents in the United States get twice as much protein as they need.
Carbohydrates: Found in starches and sugars, get converted into the body's main fuel: the simple sugar glucose. Not all carbs are created equal, however. In planning meals, we want to push complex-carbohydrate foods and go easy on simple carbohydrates. Complex carbs provide sustained energy. Fats: Fat should make up no more than 30% of the diet. Fat supplies energy and assists the body in absorbing the fat-soluble vitamins: A, D, E, and K. But these benefits must be considered next to its many adverse effects on health.
Vitamins and Minerals: A well-rounded diet based on the USDA guidelines should deliver sufficient amounts of all the essential vitamins and minerals. Adolescents tend to most often fall short of their daily quotas of calcium, iron, zinc, and vitamin D.
INFECTIOUS DISEASES An infectious disease is a disease resulting from the presence of pathogenic microbial agent. Infectious diseases are disorders caused by organisms — such as bacteria, viruses, fungi or parasites. Many organisms live in and on our bodies. They're normally harmless or even helpful, but under certain conditions, some organisms may cause disease. Some infectious diseases can be passed from person to person. Some are transmitted by bites from insects or animals. And others are acquired by ingesting contaminated food or water or being exposed to organisms in the environment. Signs and symptoms vary depending on the organism causing the infection, but often include fever and fatigue.
Causes of infectious diseases Infectious diseases are caused by: •Germs (bacteria, viruses, parasites, and fungi) which are tiny living things that are found everywhere, in the air, the soil, and water.
•Touching, eating, drinking or breathing something that contains a germ. •Food contamination.
•Direct contact (person to person, animal to person, and person to an object). Kissing, sexual contact.
•An insect bite.
How does infectious diseases spread? • Ø Ø • • • • • •
Germs spread in the air as: Small droplets. Tiny aerosol particles. Through the contact with faeces (poo) and then with the mouth. Skin or mucous membrane contact. Through the blood or other body fluids. Through contaminated food or water. Insects with viruses. From a mother to her unborn child.
Defenses for infections Nonspecific defenses
A nonspecific defense is a kind of defense that is not specialized for a particular kind of invade, it is a general defense against any germ. There are two levels:
1) First line of defense: Barriers • •
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Skin: Barrier on the outside of the body. Sweat glands produce oily acidic liquids that inhibit pathogens. Mucous membranes: Barriers on the inside of the body, secrete many kinds of fluids like: saliva, tears, nasal secretions, etc., which contain lysozyme, an enzyme that digest the cell walls of bacteria. Mucus can trap pathogens due to its viscosity. Cilia: Small hairs lining the respiratory system that beat away from the lungs. It moves mucus and trapped particles out of the body. Gastric Juice: The concentrated Hydrochloric acid (HCL) and proteases destroy pathogens in the stomach.
2) Second line of defense: Internal defenses If the pathogen penetrates the first line of defense, the barriers, the body uses its second line of defense, composed of three parts:
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Leukocytes (white blood cells): They are classified in phagocytes, the most important part in this line of defense, and lymphocytes that are part of the specific defense mechanism. • Antimicrobial proteins: Two different antimicrobial protein systems exist: Ø The complement system: Composed of twenty different proteins that help to activate the inflammatory response and attract phagocytes to the site of infection, they also attach to microbes, helping phagocytes destroy them and help lyse the cell membrane of microbes. Ø Interferons: When cells are infected by a virus, they produce small amounts of proteins called interferons, which increase the resistance of neighboring cells to infection by the same or other viruses. They seem to do this by inhibiting viral reproduction. •
The Inflammation response: Damage to tissue occurs, the White blood cells in the tissue are stimulated to release histamine. Histamine causes the capillaries to dilate and become leaky, this results in increased blood flow to the area. Blood plasma and phagocytes leak out of the capillaries and into the infected tissue, this causes the site of injury to swell, become red, warm, and tender.
Complement proteins are released to attract phagocytes which engulf microbes and infected/damaged cells.
Specific defenses: Immune System The specific defenses of the immune system kill any substance or rare cells that enter into the body. They respond to a certain kind of pathogen. The immune system recognize all the cells and proteins that are from our body and consider them as proper; the immune system also recognize strange organisms or cells that don’t are from our body, and it attack them to protect our body. The immune specific defenses are activated by molecules called antigens which stimulate any immune response. The lymphocytes B and the lymphocytes T are capable to recognize a certain antigen.
The immune system in action The cells B and T search antigens or signals of them in all the body. The immune specific response have principal actions: •
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The humoral immunity: It depend in the action of the antibodies that are in the blood. This response is activated when the antibodies that are in some B cells unite the antigens that are in the outside of the pathogen. The cell-mediated immunity: It defends the body against viruses, fungi and unicellular pathogens. The T cells also protects the body if its cells become carcinogenic.
HIV/AIDS The human immunodeficiency virus (HIV) is a lentivirus (a subgroup of retrovirus) that causes HIV infection and over time acquired immunodeficiency syndrome (AIDS.). AIDS is a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Without treatment, average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype. Infection with HIV occurs by the transfer of blood, semen, vaginal fluid, pre-ejaculate, or breast milk. Within these bodily fluids, HIV is present as both free virus particles and virus within infected immune cells. Human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS) is a spectrum of conditions caused by infection with the human immunodeficiency virus (HIV). Following initial infection, a person may not notice
any symptoms or may experience a brief period of influenza-like illness. Typically, this is followed by a prolonged period with no symptoms. As the infection progresses, it interferes more with the immune system, increasing the risk of common infections like tuberculosis, as well as other opportunistic infections, and tumors that rarely affect people who have working immune systems. These late symptoms of infection are referred to as AIDS. This stage is often also associated with weight loss.
HUMAN BODY ORGANIZATION Cells are the basic units of structure and function in the human body, as they are in all living things. Each cell carries out basic life processes that allow the body to survive. Many human cells are specialized in form and function.
After the cell, the tissue is the next level of organization in the human body. A tissue is a group of connected cells that have a similar function. There are four basic types of human tissues: epithelial, muscle, nervous, and connective tissues. These four tissue types. Make up all the organs of the human body.
An organ is an anatomically distinct structure of the body composed of two or more tissue types. Each organ performs one or more specific physiological functions.
Organs system
After tissues, organs are the next level of organization of the human body. An organ is a structure that consists of two or more types of tissues that work together to do the same job. An organ system is a group of organs that work together to carry out a complex overall function. Each organ of the system does part of the larger job.
DIGESTIVE SYSTEM The digestive system is responsible for taking whole foods and turning them into energy and nutrients to allow the body to function, grow, and repair itself. The six primary processes of the digestive system include: 1. 1. Ingestion of food 2. 2. Secretion of fluids and digestive enzymes 3. 3. Mixing and movement of food and wastes through the body 4. 4. Digestion of food into smaller pieces 5. 5. Absorption of nutrients 6. 6. Excretion of wastes
Ingestion The first function of the digestive system is ingestion, or the intake of food. The mouth is responsible for this function, as it is the orifice through which all food enters the body. The mouth and stomach are also responsible for the storage of food as it is waiting to be digested. This storage capacity allows the body to eat only a few times each day and to ingest more food than it can process at one time.
Secretion In the course of a day, the digestive system secretes around 7 liters of fluids. These fluids include saliva, mucus, hydrochloric acid, enzymes, and bile. Saliva moistens dry food and contains salivary amylase, a digestive enzyme that begins the digestion of carbohydrates. Mucus serves as a protective barrier and lubricant inside of the GI tract. Hydrochloric acid helps to digest food chemically and protects the body by killing bacteria present in our food. Enzymes are like tiny biochemical machines that disassemble large macromolecules like proteins, carbohydrates, and lipids into their smaller components. Finally, bile is used to emulsify large masses of lipids into tiny globules for easy digestion.
Mixing and Movement The digestive system uses 3 main processes to move and mix food: •
Swallowing. Swallowing is the process of using smooth and skeletal muscles in the mouth, tongue, and pharynx to push food out of the mouth, through the pharynx, and into the esophagus.
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Peristalsis. Peristalsis is a muscular wave that travels the length of the GI tract, moving partially digested food a short distance down the tract. It takes many waves of peristalsis for food to travel from the esophagus, through the stomach and intestines, and reach the end of the GI tract.
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Segmentation. Segmentation occurs only in the small intestine as short segments of intestine contract like hands squeezing a toothpaste tube. Segmentation helps to increase the absorption of nutrients by mixing food and increasing its contact with the walls of the intestine.
Digestion Digestion is the process of turning large pieces of food into its component chemicals. Mechanical digestion is the physical breakdown of large pieces of food into smaller pieces. This mode of digestion begins with the chewing of food by the teeth and is continued through the muscular mixing of food by the stomach and intestines. Bile produced by the liver is also used to mechanically break fats into smaller globules. While food is being mechanically digested it is also being chemically digested as larger and more complex molecules are being broken down into smaller molecules that are easier to absorb. Chemical digestion begins in the mouth with salivary amylase in saliva splitting complex carbohydrates into simple carbohydrates. The enzymes and acid in the stomach continue chemical digestion, but the bulk of chemical digestion takes place in the small intestine thanks to the action of the pancreas. The pancreas secretes an incredibly strong digestive cocktail known as pancreatic juice, which is capable of digesting lipids, carbohydrates, proteins and nucleic acids. By the time food has left
the duodenum, it has been reduced to its chemical building blocks—fatty acids, amino acids, monosaccharides, and nucleotides.
Absorption Once food has been reduced to its building blocks, it is ready for the body to absorb. Absorption begins in the stomach with simple molecules like water and alcohol being absorbed directly into the bloodstream. Most absorption takes place in the walls of the small intestine, which are densely folded to maximize the surface area in contact with digested food. Small blood and lymphatic vessels in the intestinal wall pick up the molecules and carry them to the rest of the body. The large intestine is also involved in the absorption of water and vitamins B and K before feces leave the body.
Excretion The final function of the digestive system is the excretion of waste in a process known as defecation. Defecation removes indigestible substances from the body so that they do not accumulate inside the gut. The timing of defecation is controlled voluntarily by the conscious part of the brain, but must be accomplished on a regular basis to prevent a backup of indigestible materials.