RESPIRATORY SYSTEM - Responsible for taking in oxygen and taking out carbon dioxide - Made up of organs that help us breathe RESPIRATION Process of air exchange Happens in the alveoli FOUR PARTS OF RESPIRATION: Ventilation – movement of air between the atmosphere and alveoli Perfusion – blood flow through the lungs Diffusion – oxygen and carbon dioxide are transferred between the alveoli and blood Regulation – respiratory muscles and nervous system (regulates depth of respiration), breathing and heart rate and maintaining homeostasis RESPIRATORY TRACT - Nose, pharynx, larynx, trachea, bronchi - Series of tubes that function as airway passages - Filter, warm and humidify air Cilia and Mucus - Cilia moves mucus to the pharynx - Traps and removes dust and pathogens in the air - Filters unknown particles - Found in trachea and in the nasal cavity o Filtered air moves to the trachea Pharynx - Where air is gathered - Food and air meets up - Contains “tonsils”, which normal function is to fight infections Larynx - Voice box Epiglottis - Flexible cartilage - Flap that covers the opening of the trachea of glottis - Automatically closes the opening of the trachea during swallowing Heimlich Maneuver – used to pop out food Trachea - Lined with ciliated columnar epithelium and mucous cells Empty tube that serves as passageway of air into the lungs Composed of hyaline cartilage Bronchi - Small air passages - Composed of hyaline cartilage – glass-like translucent cartilage - Lines with mucous membrane -> secrete mucus and cilia that sweep the mucus and paricles up and out of the airways - Two branching tubes that connect the trachea to the lungs Brochioles - Hair-like tubes that connect to the alveoli Alveoli - Very thin membrane - Allows rapid diffusion of oxygen and carbon dioxide between capillary blood and alveolar air spaces - Lined with surfactant to prevent alveolar collapse o Surfactant – mixture of lipids and proteins and helps in reduction of surface tension o Lack of Surfactant – premature infants can have Respiratory Distress Syndrome due to immaturity of lungs and persons with Chronic Obstructive Pulmonary Disease (COPD) Lungs - 3 lobes (right); 2 lobes (left) - Contains bronchi, bronchioles, alveoli Diaphragm - One of the largest muscles - Used in the process of inspiration - Inhale, diaphragm contracts - Exhale, diaphragm relaxes Pleura - Thin membrane covering the lungs Intercostal Muscles - Found between ribs - Protects the lungs - Receives impulses from medulla, respiratory control center Chest Cavity (Thoracic Cavity) - Second larhest hollow space Abdominal Cavity - Largest hollow space Contiguous Basal Laminae - Helps in diffusion of gases - Layer of extracellular matrix secreted by the epithelial cells Lungs expand and contract in response to changes in pressure inside the chest cavity - Air in ; diaphragm contracts; lungs expand (inspiration) o Intrapulmonary volume increases, intrapulonary pressure decreases 759 mmHg Air out ; diaphragm relaxes ; lungs contract (expiration) o Intrapulmonary volume decreases, intrapulonary pressure increases 761 mmHg - Residual Volume - Leftover air inside the lungs Vital Capacity - Maximum amount of air Tidal Volume - Amount of air breathed in and out NERVOUS SYSTEM ROLE - Regulates the rate and depth of respiration - Medulla oblongata is the respiratory control system of the brain - Cough reflex is stimulated by nervous system Disorders of the Respiratory System - Infections: bronchiolitis or pneumonia - Allergic disorders - Inflammatory disorders - Obstructive airway disorders o Bronchial pulmonary dysplasia – premature infants o Asthma o Clinical - COPD Manifestation – Asthma Dyspnea- difficulty in breathing Wheezing Chest tightness Cough Sputum production Extrinsic Property - Something that is not essential or inherent - Ex. Weight Intrinsic Property - Something that has of itself, independent - Ex. Density CIRCULATORY SYSTEM the lungs or urinary system to be expelled from the body. The cardiovascular system works in conjunction with the respiratory system to deliver oxygen to the tissues of the body and remove carbon dioxide. In order to do this effectively the cardiovascular system is divided into two circuits, known as the pulmonary circuit and the systemic circuit. The pulmonary circuit is made up of the heart, lungs, pulmonary veins and pulmonary arteries. This circuit pumps deoxygenated (blue) blood from the heart to the lungs where it becomes oxygenated (red) and returns to the heart. Major Functions of the Cardiovascular System On this page we take a closer look at the four major functions of the cardiovascualr system transportation, protection, fluid balance and thermoregulation. The four major functions of the cardiovascular system are: 1. To transport nutrients, gases and waste products around the body 2. To protect the body from infection and blood loss 3. To help the body maintain a constant body temperature (‘thermoregulation’) 4. To help maintain fluid balance within the body The systemic circuit is made up of the heart and all the remaining arteries, arterioles, capillaries, venules, and veins in the body. 1. Transportation of nutrients, gases and waste products The cardiovascular system acts as an internal road network, linking all parts of the body via a system of highways (arteries and veins), main roads (arterioles and venules) and streets, avenues and lanes (capillaries). This circuit pumps oxygenated (red) blood from the heart to all the tissues, muscles and organs in the body, to provide them with the nutrients and gases they need in order to function. This network allows a non-stop courier system (the blood) to deliver and expel nutrients, gases, waste products and messages throughout the body. Nutrients such as glucose from digested carbohydrate are delivered from the digestive tract to the muscles and organs that require them for energy. Hormones (chemical messengers) from endocrine glands are transported by the cardiovascular system to their target organs, and waste products are transported to After the oxygen has been delivered the systemic circuit picks up the carbon dioxide and returns this in the now deoxygenated (blue) blood, to the lungs, where it enters the pulmonary circuit to become oxygenated again. 2. Protection from infection and blood loss Blood contains three types of cells as listed below and shown in the adjacent image. 1. Red blood cells 2. White blood cells 3. Platelets Red blood cells are responsible for transporting oxygen around the body to the tissues and organs that need it. As oxygen enters the blood stream through the alveoli of the lungs it binds to a special protein in the red blood cells called haemoglobin. This can be seen in the adjacent image. The job of white blood cells is to detect foreign bodies or infections and envelop and kill them, as seen in the below image. When they detect and kill an infection they create antibodies for that particular infection which enables the immune system to act more quickly against foreign bodies or infections it has come into contact with previously. Platelets are cells which are responsible for clotting the blood, they stick to foreign particles or objects such as the edges of a cut. Platelets connect to fibrinogen (a protein which is released in the site of the cut) producing a clump that blocks the hole in the broken blood vessel. On an external wound this would become a scab. If the core temperature drops below this range it is known as hypothermia and if it rises above this range it is known as hyperthermia. As temperatures move further into hypo or hyperthermia they become life threatening. Because of this the body works continuously to maintain its core temperature within the healthy range. This process of temperature regulation in known as thermoregulation and the cardiovascular system plays an integral part. Temperature changes within the body are detected by sensory receptors called thermoreceptors, which in turn relay information about these changes to the hypothalamus in the brain. When a deviation in temperature is recorded the hypothalamus reacts by initiating certain mechanisms in order to regain a safe temperature range. There are four sites where these adjustments in temperature can occur, they are: a. Sweat glands: These glands are instructed to secrete sweat onto the surface of the skin when either the blood or skin temperature is detected to be above a normal safe temperature. This allows heat to be lost through evaporation and cools the skin so blood that has been sent to the skin can in turn be cooled. If the body has a low level of platelets then clotting may not occur and bleeding can continue. Excessive blood loss can be fatal – this is why people with a condition known as haemophilia (low levels or absence of platelets) need medication otherwise even minor cuts can become fatal as bleeding continues without a scab being formed. Alternatively, if platelet levels are excessively high then clotting within blood vessels can occur, leading to a stroke and or heart attack. This is why people with a history of cardiac problems are often prescribed medication to keep their blood thin to minimise the risk of clotting within their blood vessels. b. Smooth muscle around arterioles: Increases in temperature result in the smooth muscle in the walls of arterioles being stimulated to relax causing vasodilation (increase in diameter of the vessel). 3. Maintenance of constant body temperature (thermoregulation) The core temperature range for a healthy adult is considered to be between 36.1°C and 37.8°C, with 37°C regarded as the average ‘normal’ temperature. This in turn increases the volume of blood flow to the skin, allowing cooling to occur. We see this is in the adjacent diagram where blood that is normally concentrated around the core organs is shunted to the skin to cool when the body is under heat stress. Hyperhydration on the other hand results from an excessive intake of water which pushes the normal balance of electrolytes outside of their safe limits. This can occur through long bouts of intensive exercise where electrolytes are not replenished and excessive amounts of water are consumed. If however the thermoreceptors detect a cooling of the blood or skin then the hypothalamus reacts by sending a message to the smooth muscle of the arteriole walls causing the arterioles to vasoconstrict (reduce their diameter), thus reducing the blood flow to the skin and therefore helping to maintain core body temperature. c. Skeletal muscle: When a drop in blood temperature is recorded the hypothalamus can also react by causing skeletal muscles to start shivering. Shivering is actually lots of very fast, small muscular contractions which produce heat to help warm the blood This can result in the recently consumed fluid rushing into the body’s cells, causing tissues to swell. If this swelling occurs in the brain it can put excessive pressure on the brain stem that may result in seizures, brain damage, coma or even death. Dehydration or a loss of body fluid (through sweat, urination, bleeding etc) results in an increase in ‘blood tonicity’ (the concentration of substances within the blood) and a decrease in blood volume. Where as hyperhydration or a gain in body fluid (intake of water) usually results in a reduction of blood tonicity and an increase in blood volume. d. Endocrine glands: The hypothalamus may trigger the release of hormones such as thyroxin, adrenalin and noradrenalin in response to drops in blood temperature. These hormones all contribute to increasing the bodies metabolic rate (rate at which the body burns fuel) and therefore increasing the production of heat. 4. Maintaining fluid balance within the body Any change in blood tonicity and volume is detected by the kidneys and osmoreceptors in the hypothalamus. The cardiovascular system works in conjunction with other body systems (nervous and endocrine) to balance the body’s fluid levels. Fluid balance is essential in order to ensure sufficient and efficient movement of electrolytes, nutrients and gases through the body’s cells. Osmoreceptors are specialist receptors that detect changes in the dilution of the blood. Essentially they detect if we are hydrated (diluted blood) or dehydrated (less diluted blood). When the fluid levels in the body do not balance a state of dehydration or hyperhydration can occur, both of which impede normal body function and if left unchecked can become dangerous or even fatal. Dehydration is the excessive loss of body fluid, usually accompanied by an excessive loss of electrolytes. The symptoms of dehydration include; headaches, cramps, dizziness, fainting and raised blood pressure (blood becomes thicker as its volume decreases requiring more force to pump it around the body). In response hormones are released and transported by the cardiovascular system (through the blood) to act on target tissues such as the kidneys to increase or decrease urine production. Another way the cardiovascular system maintains fluid balance is by either dilating (widening) or constricting (tightening) blood vessels to increase or decrease the amount of fluid that can be lost through sweat. TYPES OF CIRCULATION Pulmonary Circulation o Movement of blood from heart to lungs and back to heart Coronary Circulation Movement of blood throughout the tissues of the heart Systemic Circulation o Movement of blood from heart to the rest of the body excluding lungs o PARTS OF THE CIRCULATORY SYSTEM Heart - Pumps blood throughout the body 4 Chambers - Atrium – receiving chamber - Ventricle – forces blood out into the arteries or veins Valve - Between each atrium and ventricle Prevents blood from flowing backwards Control movement of blood into the heart chambers Blood Vessel - Carries blood throughout the body o Arteries – carry blood away from the heart o Veins – carry blood to the heart o Capillaries Smallest blood vessels Connects smalles arteries to smallest veins Site where gases and nutrients are exchanged Inferior vena cava - Blood from the lover body Superior vena cava - Blood from the upper body Deoxygenated Blood 1. Vena cava 2. R. atrium 3. Tricuspid valve 4. R. ventricle 5. Pulmonary valve 6. Pulmonary artery 7. Lungs Oxygenated Blood 1. Lungs 2. L & R pulmonary veins 3. 4. 5. 6. 7. L. atrium Bicuspid valve L. ventricle Aortic valve Aorta Heart Rate - Pulse per minute - BPM- beats per minute LYMPHATIC SYSTEM The lymphatic system consists of the following: Fluid, known as lymph Vessels that transport lymph Organs that contain lymphoid tissue (eg, lymph nodes, spleen, and thymus) Table 1. Key Components of Lymphatic System Organ Function Lymph Contains nutrients, oxygen, hormones, and fatty acids, as well as toxins and cellular waste products, that are transported to and from cellular tissues Lymphatic Transport lymph from peripheral vessels tissues to the veins of the cardiovascular system Lymph Monitors the composition of lymph, the nodes location of pathogen engulfment and Spleen Thymus eradication, the immunologic response, and the regulation site Monitors the composition of blood components, the location of pathogen engulfment and eradication, the immunologic response, and the regulation site Serves as the site of T-lymphocyte maturation, development, and control The lymphatic system’s main functions are as follows: Restoration of excess interstitial fluid and proteins to the blood Absorption of fats and fat-soluble vitamins from the digestive system and transport of these elements to the venous circulation Defense against invading organisms Genetics: Mendelian Inheritance & Heredity - Genetics – study of genes and inheritance (passing genetic information through genes). - Father of Genetics: Gregor Mendel, Austrian Monk. - Heredity – passing of charateristics from parents to their offspring. Two view points of heredity: “Blending” hypothesis is the idea that genetic material from two parents blends together. example: blue + yellow = green “Particulate” hypothesis is the idea that parents pass on discrete heritable units (genes) How does heredity work? Genes - functional units of DNA that code for specific traits. Example: plant height example: pea color Peyer’s patches: These patches of lymphoid tissue are located in the mucosa and submucosa throughout the small intestine, although they’re more concentrated in the ileum. Peyer’s patches contain mostly B cells. Lamina propria lymphocytes: This type of GALT is located in the mucosa of the small intestine. It also contains mostly B cells. Intraepithelial lymphocytes: These tissues are located between the cells of the epithelial layer of the small intestine, between the tight junctions. Traits – are specific characteristics that vary from individual to individual as coded by the DNA. Example: short/tall example: yellow/green DNA- important molecule where all living things are based through which the genetic code are coded. Genetics Terminology: Chromosomes & Genes • • • Genome - Complete complement of organism’s DNA. Cellular DNA in organized chromosome. Gene have specific places on chromosomes. an So who was Mendel? • Once upon a time (1860's), in an Austrian monastery, there lived a monk named Gregor Mendel. • Mendel spent his spare time breeding pea plants. • He did this over & over & over again, and noticed patterns to the inheritance of traits, from one set of pea plants to the next. • By carefully analyzing his pea plant numbers, he discovered three laws of inheritance. Mendel's Laws are as follows: 1. 2. 3. 4. • Law of Dominance Law of Segregation Law of Independent Assortment We label the different generations of a cross as: • P generation (parents) • F1 generation (1st filial generation) • F2 generation (2nd filial generation) In his work, the words "chromosomes" or "genes" are nowhere to be found. The role of these things in relation to inheritance & heredity had not been discovered yet. What makes Mendel's contributions so impressive is that he described the basic patterns of inheritance before the mechanism for inheritance (namely genes) was even discovered! • First, a little more genetics terminology. Mendel's Laws 1. Law of Dominance 2. Law of Segregation 3. Law of Independent Assortment Genetics Terminology Has functional unit of DNA coded in it: the genes of an organism (all your genes) Characteristics: an organism’s (expression of your genes) 1. Mendel’s Law of Dominance • Genes and Dominance A single gene can have one or more factors for a particular trait. Alleles are the variations of a gene. Example: Gene for flower color Alleles: purple allele and white allele Alleles can be dominant or recessive. Mendel’s Principle of Dominance, “ some alleles are dominant and others are recessive.” In complete dominance, if the dominant allele is present the dominant trait will be expressed. The recessive trait will only be present if the two recessive alleles are in the gene. The alleles of a gene are usually represented by the dominant trait. Example: Gene flower color (purple is dominant) Alleles: P (purple) p (white) traits allele: variations of a gene o Represented with letters for the different types of alleles (PP, Pp, pp) – genes genotype homozygous: pair of identical alleles for a character (PP, pp) heterozygous: two different alleles for a gene (Pp) Character: heritable feature (i.e., fur color) Trait: variant for a character (i.e. brown) True-bred: all offspring of same variety Hybridization: crossing of 2 different truebreds 2. Mendel’s Law of Segragation • The alleles for each character segregate (separate) during gamete production (formation). • Alleles for a trait are recombined at fertilization, becoming genotype for the traits of the offspring. Alleles for different traits are distributed to sex cells (& offspring) independently of one another. Each set of alleles segragate independently. Mendel’s Laws: 1. Law of Dominance: - In a cross of parents that are pure for contrasting traits, only one form of the trait will appear in the next generation. - Offspring that are hybrid for a trait will have only the dominant trait in the phenotype. 2. Law of Segregations: - During the formation of gametes (eggs or sperm), the two alleles (hereditary units) responsible for a trait separate from each other. Examples: - eye color - human blood types (ABO) - Alleles for a trait are then "recombined" at fertilization, producing the genotype for the traits of the offspring. 3. Law of Independent Assortment: - Alleles for different traits are distributed to sex cells (& offspring) independently of one another. Beyond Simple Inheritance: multiple alleles Two alleles affect the phenotype in separate, distinguishable ways. Example: AB Blood Type - has three alleles: A, B FIGURING OUT PATTERNS OF INHERITANCE &O A Punnett square is a tool for diagramming the possible genotypes of offspring. - AB co-dominant, O recessive - genotype represented So far, we’ve discussed Simple Inheritance & Punnett Squares… But, of course, genetic is much more complicated than that. Let’s explore: • Incomplete dominance • Multiple alleles/ polygenic • Co-dominance • Sex-related genes (sex-linked, sex-limited and sex-influenced traits) • Beyond Simple Inheritance: Incomplete Dominance • Patterns of dominance often go beyond simple dominant or recessive traits. • Incomplete dominance has “degrees”. It is not complete. F1 generation’s appearance between the phenotypes of the 2 parents. Ex: snapdragons Beyond Simple Inheritance: multiple alleles When there are more than two possible alleles for a gene. using IA, IB & i • Co-dominance : multiple alleles - Has three alleles: A, B & O - AB co-dominant, O recessive - Genotype represented using IA, IB & i ABO Blood Type You make antibodies against the antigens of other blood types. . – Q: Which blood type can accept anyone's blood. – Q: Which blood type is known as the “universal donor. Why? • ABO Blood Type If you are infused with incompatible blood, clump occurs. The antigens in your blood bind to the antibodies of the donor blood and cause the blood to clump. • Sex-Linked Inheritance • Review • Males have an X and a Y chromosome • Females have two X chromosomes • These chromosomes determine sex, so genes located on these chromosomes are known as sexlinked genes. • Hypertrichosis Pinnae Auris • Example of Y-linked trait (found in Y chromosome) • Genetic disorder in humans that causes hairy ears • Only males can have the trait • Sex-Limited Traits • Autosomal which mean that they are not found on the X and Y chromosomes. • • • Expressed only in one gender The genes are expressed in the phenotype of an individual Expression in Lactation in Cattle (expressed only in female) Female Genotypes XXLL XXLI XXII Male Genotypes XYLL XYLI XYII • • • Female Phenotypes Female lactating Female lactating Female not lactating Male Phenotypes Male not lactating Male not lactating Male not lactating Sex-Influenced Traits Autosomal meaning their genes are not carried on the sex chromosomes. The trait of the phenotype is expressed unusually through the difference in the ways the two genders express the genes. Pattern Baldness • Not restricted to male • Has 2 alleles “bald and non-bald” • The products of the genes are highly influenced by the hormones (testosterone) • Males has much higher level of testosterone than females. • Baldness behaves as dominant allele for male and recessive for females. Extinction occurs when the last existing member of a given species dies In other words…there aren’t any more left! It is a scientific certainty when there are not any surviving individuals left to reproduce Functional Extinction Only a handful of individuals are left Odds of reproduction are slim Causes of Extinction Genetics and Demographics Small populations = increased risk Mutations Causes a flux in natural selection Beneficial genetic traits are overruled Loss of Genetic Diversity Shallow gene pools promote massive inbreeding Causes Con’t. Habitat Degradation One of the most influential Has many causes Some due to humans Some due to other factors Habitat Degradation Expression of Pattern Baldness in Humans Male Genotypes Male Phenotypes XYBB Male Bald XYBb Male Bald XYbb Male nonbald Female Genotypes Female Genotypes XXBB Female bald XXBb Female nonbald XXbb Female nonbald Toxicity Kills off species food/water directly Can occur in short spans (a single generation) Can occur over several generations • Increasing toxicity • Increasing competition habitat resources • Habitat Degradation through Destruction of Habitat “Save the Rainforests!” EXTINCTION Elimination of living space What is Extinction? Change in habitat for • Leads to diminishing resources • Rainforest to pasture lands A sharp decrease in the number of species on Earth in a short period of time Coincides with a sharp drop in speciation Predation Competition Disease The process by which new biological species arise There have been at least 5 Last one was 65M years ago Mass Extinction Coextinction Mass Extinction Planned Extinction Introduction of predators Invasive alien species Transported by humans • Cattle, rats, zebra muscles, etc… • Sometimes on sometimes not Can eat other species Eat food sources Introduce diseases Nearly 2/3rds (or more) of all animal species that ever existed on the planet are now gone. • Predation Volcanoes, floods, drought, etc… Causes Con’t. Aka: an extinction event Increases competition Can be caused by natural processes • purpose, With contemporary extinction being attributed to HUMAN activity. Numerous factors go into the extinction of a specific species. • Though all point the finger to climate change. • Mass Extinction Began about three-million years ago (Continental Glaciations). Hypotheses for initial extinction: • Sea level depletion Temperature decrease Though these hypotheses aren’t mutually exclusive, they may have conspired together. Coextinction Mass Extinctions The loss of one species leads to the loss of another 1. Chain of extinction 2. End Triassic Extinction (200). Can be caused by small impacts in the beginning 3. Permian Triassic Extinction (250). A predator looses its food source 4. Late Devonian Extinction (364). Affected by interconnectedness in nature 5. Ordovician-Silurian Extinction (440). 6. Mass Extinction vs. Cretaceous-Tertiary Extinction (65). (#= millions of years ago) Planned Extinction Human controlled Thought of to help humans Deadly viruses Smallpox • Extinct in the wild Polio • Near extinct (only in small parts of the world) Asteroids Causes complete devastation Flattening and crater at or around impact sitehundreds of miles wide Reverberations felt around the world Acid Rain • In the Americas—80% of large animals became extinct around the same time as first human presence there Based on these, and other studies done by The international Union for Conservation of Nature and Natural Resources (IUCN), human induced extinctions are not necessarily a new phenomena. However, extinction by humans today is becoming much more rapid. The rapid loss of species today is estimated by some experts to be between 100 and 1,000 times higher than the natural extinction rate, while others estimate rates as high as 1,000-11,000 times higher. Habitat Degradation Habitat loss and degradation affect 86% of all threatened birds, 86% of mammals and 88% of threatened amphibians Kills acid intolerant species Climate change/Global Warming Disease/Epidemics Can wipe out entire species Frog with fungus disease Killing frogs and other amphibians Top Human Causes of Extinction: Increased human population Destruction/Fragmentation of habitat Pollution John W. Williams from UW-Madison suggests that changes in regions such as the Peruvian Andes, portions of the Himalayas and southern Australia could have a profound impact on indigenous plants and animals Williams and his research partners used computer models to estimate how various parts of the world would be affected by regional changes consistent with the IPCC's climate models. Their findings indicated that “By the end of the 21st century, large portions of the Earth’s surface may experience climates not found at present and some 20th century climates may disappear.” Climate change/Global warming Extinctions caused by humans are generally considered to be a recent phenomena. HOWEVER: • In Australia—earliest humans: 64,000 years ago extinction—30,000-60,000 years ago Their studies also suggest isolated climates such as the Peruvian Andes could change drastically enough to lead to species extinctions. The climate change might also create new climates, providing new opportunities for other species to thrive, Williams said. Regions where novel climates are expected to form in tropical and subtropical regions include the western Sahara, southeastern U.S. and eastern India. Food and drink Medicines Where and what are hotspots? Industrial materials Ecological services Leisurely, cultural, and aesthetic values “The concept of biodiversity hotspots was penned by British ecologist Norman Myers in 1988 as a means to address the dilemma of identifying the areas most important for preserving species.” (national geographic) Hotspots are included in 6 continents excluding Antarctica. Hotspots are heavily distributed along shore lines and near the equator. Hotspots including are affected Logging Agriculture Hunting Climate change Government by many factors Hotspots can be added and removed from the classification of “hotspot” by what recovery or lack of prevention is taking place in each area. What is required to be considered a hotspot “The region must support at least 1,500 plant species found nowhere else in the world, and it must have lost at least 70 percent of its original habitat.” Biodiversity Causes of Biodiversity Loss Pollution Loss of tropical forest Spread of urban areas Warfare Large dam construction Road building Tourism Loss of traditional lifestyles Consequences of Biodiversity Loss Loss of food Collapse of food web Loss of keystone species Reduction of ecosystem community productivity Loss of medicinal supplies Increased vulnerability of species to disease and predation efficiency and Population Biodiversity is the variation of taxonomic life forms for a given biome or ecosystem Pertains to the number of organisms of the same species living in a certain place. Boosts Ecosystem productivity Communities with many different species Measure of the health of a biological system (a high index of diversity) will be able to withstand environmental changes better than communities with only a few species Benefits of Biodiversity ( a low index of diversity). Particular species that decline so fast that it becomes endangered In a study conducted by field of biologist on population size and distribution of Philippine fauna, they reported that as of 1991, 89 species of birds, 44 species of mammals, and eight species of reptiles are internationally recognized as threatened. Population Density Number of individual per unit area. Factors affecting the population growth and size: Members moving and out the ecosystem Death and birth rates Extinction Limiting Factors Anything that limits the size of a population from increasing and help balance an ecosystem. The disappearance of a species when the last of its members die. Changes to habitats Availability of foods Increase in population of people Water Living conditions Impact of growth and development altering face of the earth Light Clearing of natural vegetation Soil nutrients Concrete structures Natural disasters Human activities Replacement of a new community or development of a new environment Help determines the type of organisms that can live in an ecosystem Carrying Capacity The maximum population size an environment can support. Organisms die if population size rises above their carrying capacity because it cannot meet their needs. Local and global environmental issues that contributed to species extinction: Deforestation – rapid rate at which trees are cut down. Major causes: Endangered When a species, population become so low that only a few remain and will possibly extinct kaingin farming Illegal logging Conversion of agricultural lands to housing projects Tamaraw in Mindoro Mouse deer in Palawan (Philippine deer) Forest fires Monkey-eating eagle Typhoons Aquatic species (dugong in Negros, Batangas, and Leyte) Threatened Consequences, Soil erosion Floods Decrease in wildlife resources that will eventually lead to extinction Wildlife depletion – as human population gets bigger, huge space is needed for shelter, for growing crops and for industries. Supposed to be slow process but man’s activities hasten its depletion Process: PCBs are dumped into water Algae have 100 times more PCBs than water as they feed on it. Small fish feeds on algae. They have 100 times more PCBs than algae but were not killed yet store them in their tissues. As salmon feed on small fish they took PCBs in their bodies. The concentration of PCB in salmon rise to 5000 times the concentration of PCB in the water in which they feed. Other pollutant found in water are heavy metals lead, mercury, cadmium – comes from factories that dumped their wastes into the rivers or lakes. Major cause Euthrophication – effects of water pollution process: deforestation sewage carries chemicals into young lakes. These chemicals speed up growth of algae (algal bloom and aquatic plants) Algae die and settle to the bottom. They begin to decompose. Bacteria that cause decomposition use up oxygen in water. major causes As a result, aquatic animals die due to lack of oxygen (fish kills). Biological Magnification – build up of pollutants in organisms at higher trophic levels in a food chain. Bodies of water are polluted with toxic wastes, untreated sewage, and fertilizer run offs from farm lands. One class of chemical present in water is PCB (polychlorinated biphenyl). PCBs – toxic wastes produced in the making of paints, inks, and electrical insulators. That causes major effect in the food chain. - at each food chain, the amount of PCB in each organism increases. They are unable to excrete PCB from their bodies. Through biological magnification, PCB becomes concentrated in the body of water organisms. Air Pollution - contaminated ecosystems contain built up high concentration of PCB. cars factories industries power plants Process: nitrogen oxides and hydrocarbons from car exhausts react with water vapour or dust particles and produce new irritating chemicals. Burning of coal. Coal contains sulfur. When coal burns, sulfur combine with oxygen in the air to form sulfur dioxide with choking odor. Burning coal gives off particulates into the air. Particulates are tiny particles of soot, and dust. These particulates block sunlight and get into our system when we breathe. Global warming – is an increase in the earth’s temperature from the rapid build up of carbon dioxide and other gases. This, in turn, could change the world climate patterns. -carbon dioxide acts like a blanket over the earth, holding in the heat that would otherwise radiate back into space. Greenhouse effect – the trapping of heat by gases in the earth’s atmosphere. - greenhouse effect is a natural process. But as carbon dioxide in the atmosphere increases, greenhouse effect also intensifies – this will lead to global warming. Tropical Forest Cutting Cover 13% of Earth Home to 50% of all known plant and animal species FAO reports 15.4 million hectares are destroyed annually -global The Convention on Biological Diversity Mission Statement Destruction of Coastal Resources “The objectives of this convention are the conservation of biological diversity, sustainable use of its components and the fair and equitable sharing of the benefits arising out of the utilization of genetic resources.” major causes deforestation, agricultural activities and mining activities Dynamite fishing and muro-ami Coastal areas conversion to beach resorts, residential areas Overharvesting --man’s activities areas through the years. destroyed coastal --coral reefs and coastal mangroves forests serves as a breeding grounds and nurseries of marine fishes. Acid precipitation/rain - CO2 makes rainwater acidic. - presence of other pollutants from emissions from factories and from exhaust of motor vehicles contains sulfur and nitrogen oxides which makes rainwater more acidic, with pH 5.6 or lower. Effects of acid yellowing and falling off of leaves. rain are Crops Monoculture of crops lets the yield become susceptible to pests or viruses 75% of crop varieties are extinct Due to the spread of modern agriculture Since it was adopted at the Earth Summit in Rio de Janeiro in 1992, 189 countries have signed and implemented it. The United States signed it in 1993 but has yet to put it into action still today 2010 Biodiversity Target Members adopted a plan to significantly reduce the present rate of biodiversity loss at the global, regional and national level by the year 2010.
