Introductory Biology II Final Exam Study Guide (BIOL 104)

Biology 104 Final Exam Chapter 21 Classify an animal into its nutritional category (herbivore, carnivore, or omnivore) based on examples of their diets “An animal whose diet consists of green vegetables and spider falls into what nutritional category?” Omnivore Herbivores eat mainly autotrophs (plants and algae) Carnivores eat other animals Omnivores regularly consume animals as well as plants or algal matter Understand what defines a nutrient as either essential or non-essential “An essential nutrient does not have which of the following characteristics? Can be synthesized from molecules in the diet” Essential nutrients are required by cells and must be obtained from dietary sources: Essential amino acids, Essential fatty acids, Vitamins & Minerals Animals require 20 amino acids and can synthesize about half from molecules in their diet. The remaining amino acids, the essential amino acids, must be obtained from food in preassembled form Nonessential nutrients are those nutrients that can be made by the body; they may often also be absorbed from consumed food. Distinguish between undernourishment and malnourishment, know what the problem is under both conditions “A person who is overweight and has an iron deficiency falls into what general nourishment deficiency category?” Malnourishment Undernourishment is the result of a diet that consistently supplies less chemical energy than the body requires An undernourished individual will: Use up stored fat and carbohydrates Break down its own proteins Lose muscle mass Suffer protein deficiency of the brain Die or suffer irreversible damage Malnourishment is the long-term absence from the diet of one or more essential nutrients Malnourishment can cause deformities, disease, and death Malnourishment can be corrected by changes to a diet Understand the three needs of a healthy diet “Which of the following is not a requirement for a healthy diet?” Water to maintain temperature homeostasis Fuel to power the body Organic molecules to build molecules Essential nutrients—raw materials that animals cannot make for themselves Understand the different ways the body deals with fats and sugars “Fats are best used for energy storage, as:” sugars are quickly broken down directly from the bloodstream Nearly all of an animal’s ATP generation is based on oxidation of energy-rich molecules: carbohydrates, proteins, and fats Animals store excess calories primarily as glycogen in the liver and muscles Energy is secondarily stored as adipose, or fat, cells Know the role of insulin in maintaining homeostasis “The role of insulin is to signal cells in the body to uptake what molecule into the bloodstream?” Glucose The human body mandates that blood glucose is maintained at a very narrow range Homeostasis is regulated by two hormones: insulin and glucagon, which are both secreted by the pancreas Insulin is secreted by beta cells of the pancreas in response to high blood sugar, although a low level is always secreted by the pancreas After a meal, the amount of insulin in the blood increases as the blood glucose rises As blood glucose falls, insulin secretion from the pancreas decreases In response to insulin, red blood, muscle, and fat cells take glucose from the blood, which ultimately lowers the high blood glucose levels back to normal Understand the relationship between Ghrelin and antibiotics “H. pylori infections that are treated with antibiotics sometimes lead to weight gain because of the interruption of what molecular interaction” Ghrelin & H. pylori In a study, antibiotics for H pylori bacteria increased blood levels of the “hunger hormone” ghrelin by 6 times, and the hormone stayed high for 18 months. Made by stomach cells (and normally suppressed by H Pylori), ghrelin is a strong appetite stimulant and promoter of belly fat. Why did evolution lead us to become a fat gorging society? “Our survival instinct leads to a general preference within the human population for:” Fats Understand the main stages of food processing and where they occur within the human body “The primary site for absorption of nutrients into the body is what organ?” Small Intestine “The hallmark of a simple digestive tract is the presence of a single location for the digestion of food as well as what?” Distribution of nutrients “This organ is involved in ingestion and formation of the bolus.” Tongue “This regulatory mechanism allows for the one-way movement of objects through the digestive system.” Sphincter “This organ serves as a storage place for secretions from an accessory digestive organ.” Gall Bladder “This is the largest internal organ, and is the major organ of digestion and absorption.” Small Intestine “This organ serves as a storage place for microflora.” Appendix Absorption= large intestine (the colon of the large intestine is connected to small intestine) Appendix= extension of human cecum, plays very minor role in immunity Colon= recover water that has entered alimentary canal Know the four types of feeding systems and what the diet of each system consists of. “An animal that is a fluid feeder will get most of its nutrient-rich fluid from what source? Living Organisms Suspension Feeders: sift small food particles from the water (many aquatic animals) Substrate feeders: animals that live in or on their food source (ex. A caterpillar) Fluid feeders: suck nutrient-rich fluid from a living host (ex. A mosquito) Bulk feeders eat relatively large pieces of food (ex. A boa constrictor) Chapter 22&23 Know the roles of arteries, veins, and capillaries along with the composition of the blood in each vessel “This circulatory vessel is responsible for the movement of blood against gravity and towards the heart” Vein “Arteries have thicker walls than veins in order to accommodate what?” Increased Pressure “Carbon dioxide concentration is highest in which blood vessel?” Veins Arteries branch into arterioles and carry blood to capillaries Networks of capillaries called capillary beds are the sites of chemical exchange between the blood and interstitial fluid Venules converge into veins and return blood from capillaries to the heart “Veins that are blue in color have blood that is what?” Darker Red than Arteries “In a single circulation the blood in the heart is” Dark Red Know what the pulmocutaneous circuit is and understand its role in amphibians “The frog is able to breathe underwater by closing blood flow to the lungs and redirecting it to the skin as a part of what system?” Pulmocutaneous circuit In amphibians, oxygen-poor blood flows through a pulmocutaneous circuit to pick up oxygen through the lungs and skin In reptiles and mammals, oxygen-poor blood flows through the pulmonary circuit to pick up oxygen through the lungs Know why humans need oxygen, what molecular reaction does oxygen aid in? “Humans breathe oxygen because cells use this molecule during the breakdown of what molecule?” Sugar Understand the difference between the atrium and the ventricles “This region of the heart is where blood is pushed out during systolic contraction.” Ventricle Blood enters through an atrium and is pumped out through a ventricle Know the difference between pulmonary and systemic capillaries “The exchange of carbon dioxide from lymph fluid and blood occurs at what group of capillaries” Systemic Capillaries Differentiate between systole and diastole. Why is systolic pressure higher than diastolic? “The region of the heart where blood is pushed out during systolic contraction.” Ventricle Systolic pressure is the pressure in the arteries during ventricular systole; it is the highest pressure in the arteries Diastolic pressure is the pressure in the arteries during diastole; it is lower than systolic pressure Differentiate between a heart attack and stroke “This event occurs when blood flow to the brain is blocked and may result in permanent brain damage” Stroke A heart attack is the death of cardiac muscle tissue resulting from blockage of one or more coronary arteries A stroke is the death of nervous tissue in the brain, usually resulting from rupture or blockage of arteries in the head Know the cause of atherosclerosis, differentiate between HDL and LDL “The buildup of plaque in blood vessels leads to a condition known as what?” Atherosclerosis “The cholesterol molecule when not properly regulated is a major contributor to the buildup of plaques within the circulatory system” LDL Low-density lipoproteins (LDLs) are associated with plaque formation; these are “bad cholesterol” High-density lipoproteins (HDLs) reduce the deposition of cholesterol; these are “good cholesterol” The proportion of LDL relative to HDL can be decreased by exercise, not smoking, and avoiding foods with trans fats Understand the structural differences between veins, capillaries, and arteries. General characteristics rather than specific layers “Arteries have thicker walls than veins in order to accommodate what?” Increased Pressure Capillaries have thin walls, the endothelium plus its basement membrane, to facilitate the exchange of materials Arteries have thicker walls than veins to accommodate the high pressure of blood pumped from the heart In the thinner-walled veins, blood flows back to the heart mainly as a result of muscle action Know where and why blood flow velocities change, know where they are greatest and where they are the slowest “The velocity of blood at the capillaries is slower than both arteries and veins because of what capillary structural feature and function?” Increased surface area and gas exchange Physical laws governing movement of fluids through pipes affect blood flow and blood pressure Velocity of blood flow is slowest in the capillary beds, as a result of the high resistance and large total cross-sectional area Blood flow in capillaries is necessarily slow for exchange of materials Understand the role of vasodilation and constriction in blood pressure “Blood pressure can be regulated by both the pumping of the heart and the smooth muscle regulated response.” Vasoconstriction “When the weather is cold and you start to shiver, your blood vessels undergo which of the following to maintain heat?” Vasoconstriction Blood pressure is determined by cardiac output and peripheral resistance due to constriction of arterioles Vasoconstriction is the contraction of smooth muscle in arteriole walls; it increases blood pressure Vasodilation is the relaxation of smooth muscles in the arterioles; it causes blood pressure to fall Understand the causes of hypertension and the effect that it can have on an economy “Hypertension can be defined as what?” Increased blood pressure for a sustained period of time Hypertension causes: heart to work harder, weakening it over time; increased plaque formation from tiny ruptures; increased risk of blood clot formation, heart attacks, strokes, kidney failure Hypertension costs totaled at $73.4 Billion in 2009; prescription drugs, physician visits, hospital care, nursing home care, home health care, lost productivity due to mortality or morbidity Know why animal feint and what may lead to this event “Feinting is primarily caused by what event?” The lack of blood flow to the brain Understand how blood moves against gravity in veins Pressure from muscle contractions Between two muscles, between muscles and bone or skin—Squeezes veins One-way valves in veins prevent backflow of blood Understand the role of osmotic pressure in the movement of molecules at capillaries and know why it is important to maintain the correct mineral concentration in your body “The brain aids in the regulation of breathing rate by the measuring of what molecular concentration?” Carbon Dioxide “Carbon dioxide concentration is highest in which blood vessel?” Veins “The red blood cell is the primary oxygen carrier within our bodies, what molecule is an essential element of this blood cell that allows it to perform its functions?” Iron Osmotic pressure drives fluids out of capillaries at the arteriole end and into capillaries at the venule end Ions/ blood electrolytes help regulate Osmotic balance, pH buffering, and regulation of membrane permeability Understand what lymph fluid is and what role the lymph nodes play The lymphatic system returns fluid that leaks out in the capillary beds This system aids in body defense Fluid, called lymph, reenters the circulation directly at the venous end of the capillary bed and indirectly through the lymphatic system; the lymphatic system drains into veins in the neck Lymph nodes are organs that filter lymph and play an important role in the body’s defense Know the three major components of blood and their roles Blood consists of several kinds of cells suspended in a liquid matrix called Plasma; various plasma proteins function in lipid transport, immunity, and blood clotting Red blood cells (erythrocytes) transport oxygen White blood cells (leukocytes) function in defense Understand what a platelet is and what its role is. Know that it is NOT a cell. Platelets, a third cellular element, are fragments of cells that are involved in clotting Know how partial pressure helps move gases through the circulatory system “The movement of oxygen in and out of the blood stream at the capillaries is regulated by what gradient?” Partial Pressure of Oxygen Gases diffuse down pressure gradients in the lungs and other organs as a result of differences in partial pressure Partial pressure is the pressure exerted by a particular gas in a mixture of gases A gas diffuses from a region of higher partial pressure to a region of lower partial pressure In the lungs and tissues, O2 and CO2 diffuse from where their partial pressures are higher to where they are lower Understand why gills are more efficient than lungs “Gills must be extremely effective at the exchange of gasses primarily due to what characteristic of water as compared to air?” Water has a lower oxygen content than air “The flow of blood in the opposite direction of water along the gill exchange surface is referred to as what?” Counter Current Exchange Gills are out-foldings of the body that create a large surface area for gas exchange Chapter 24 Be able to define and distinguish between innate and acquired immunity “This type of immunity is gained after exposure to antigens and found only in vertebrates” Acquired Innate immunity is present before any exposure to pathogens and is effective from the time of birth (involves nonspecific responses to pathogens) Acquired immunity, or adaptive immunity, develops after exposure to agents such as microbes, toxins, or other foreign substances (It involves a very specific response to pathogens) Understand the role of skin and mucous membrane in innate immunity “External barriers such as the skin and mucous membrane are considered part of innate immune system because of what following concept” They are present before any exposure to pathogens and effective from birth Innate defenses include barrier defenses, phagocytosis, antimicrobial peptides Mucus traps and allows for the removal of microbes Many body fluids including saliva, mucus, and tears are hostile to microbes The low pH of skin and the digestive system prevents growth of microbes Know what a hemocyte is and the two mechanisms it uses to defend the host “The hemocyte uses these two mechanisms to defend a host from microbial challenge” Phagocytosis and antimicrobial peptide release Define the MHC and the role that it plays in NK cell protection All cells in the body (except red blood cells) have a class 1 MHC (major histocompatibility complex) protein on their surface Cancerous or infected cells no longer express this protein; natural killer (NK) cells attack these damaged cells T cells bind to antigen fragments presented on a host cell NK cell detects normal MCH expression and spares the healthy epithelial cell NK cell detects loss of MHC and kills the virus infected epithelial cell Differentiate between B-cells, T-cells, and cytokines B cells- attack invaders outside the cell, mature in the bone marrow T cells- attack invaders insider the cell, mature in the thymus Cytokines are secreted by macrophages and dendritic cells to recruit and activate lymphocytes “This molecular family is released by dendritic cells and aids to recruit and activate lymphocytes” Cytokines Know the role of the variable region in the TCR and BCR “The variable region is termed variable because of what primary characteristic?” The region varies based on specificity to the antigen it binds Variable region, composed of 110-130 amino acids, give the antibody its specificity for binding antigen. Each T cell receptor consists of two different polypeptide chains; can bind to an antigen that is free or on the surface of a pathogen The tips of the chain form a variable (V) region; the rest is a constant (C) region B cell receptors bind to specific, intact antigens The B cell receptor consists of two identical heavy chains and two identical light chains Amino acid sequence varies extensively from one B cell to another Define a plasma cell and the role that it has in long term immunity “The major role that plasma cells play in the long term memory of the immune system is the production of what molecule family?” Antibodies The first exposure to a specific antigen represents the primary immune response During this time, effector B cells called plasma cells are generated, and T cells are activated to their effector forms Plasma cells help maintain antibody production Distinguish between antibodies and BCRs “A B-cell receptor can be distinguished from an antibody primarily by what physical characteristic?” The Transmembrane Domain “During the generation of new B-cells all variable regions are tested for what important characteristic?” Reactivity Against Host Cells “The humoral immune response is considered an acquired immunity because of the involvement of what family of molecules?” Antibodies B cell receptors bind to specific, intact antigens, contain transmembrane region, light chains, and heavy chains Antibodies/immunoglobulins are structurally similar to B cell receptors but lack transmembrane regions that anchor receptors in the plasma membrane Distinguish between class I and class II MHC molecules “This surface receptor is part of a system that protects cells of the body from the immune system’s natural killer cells” MHC1 “This molecule is primarily expressed on the surface of B-cells and dendritic cells, it is used to recruit T-Helper cells” MHC 2 “A class I MHC molecule is recognized by what cellular member of the immune system?” Cytotoxic T cells Understand how clonal collection results in long term immunity and understand how the body protects against self-reactivity “The increase in local blood supply after an inflammatory response has which of the following beneficial results?” Decrease of antimicrobial proteins to the site of the injury Distinguish between humoral and cell-mediated immune responses “The humoral immune response is considered an acquired immunity because of the involvement of what family of molecules?” Antibodies Humoral immune response involves activation and clonal selection of B cells, resulting in production of secreted antibodies Cell-mediated immune response involves activation and clonal selection of cytotoxic T cells Helper T cells aid both responses Know the difference between active and passive immunity, understand the role this plays in immunization Active immunity develops naturally in response to an infection, can develop following immunization Passive immunity provides immediate, short-term protection, it is conferred naturally when IgG crosses the placenta from mother to fetus or when IgA passes from mother to infant in breast milk It can be conferred artificially by injecting antibodies into a non-immune person “The short term immunity that is passed when IgG crosses the placenta is an example of what?” Passive Immunity Chapter 26 Define a hormone and distinguish between endocrine and paracrine signaling Hormones are chemical signals that are secreted into the circulatory system and communicate regulatory messages within the body Hormones reach all parts of the body, but only target cells are equipped to respond “A chemical signal that is released from a cell to communicate in a nearby (local communication) cells cluster is involved in what kind of signaling?” Paracrine “Long-term developmental processes are primarily regulated by what system?” Endocrine Distinguish between pheromones and all other hormones “A pheromone differs greatly from other hormones because of its role in communication with what?” Cells within nearby animal bodies Know where the receptors for lipid soluble molecules are and why it is different for the water soluble receptors “A water soluble hormone searches for target cell receptor proteins on what organelle of the cell?” The Plasma Membrane Water-soluble hormones are secreted by exocytosis, travel freely in the bloodstream, and bind to cell-surface receptors Lipid-soluble hormones diffuse across cell membranes, travel in the bloodstream bound to transport proteins, and diffuse through the membrane of target cells The solubility of a hormone correlates with the location of receptors inside or on the surface of target cells Understand the concept of the signal transduction pathway and what role the second messenger plays “The secondary messenger in signal transduction is termed secondary because of what function?” The transfer of surface initiated signal into the nucleus Signal transduction pathway leading to responses in the cytoplasm, enzyme activation, or a change in gene expression This triggers the release of messenger molecules that activate enzymes and result in the release of glucose into the bloodstream Know how one hormone can have a different effect on different cell types and on the same cell type “A hormone may affect two different cells in two different ways due to the presence of what?” Different hormone receptors Be able to identify and distinguish between positive and negative feedback “Bicarbonate release from the pancreas results in the increase of pH within the duodenum. This release is initiated by a low pH within the duodenum. This system is an example of what kind of feedback?” Negative A negative feedback loop inhibits a response by reducing the initial stimulus Negative feedback regulates many hormonal pathways involved in homeostasis In a positive feedback system, the output enhances the original stimulus. A good example of a positive feedback system is child birth. During labor, a hormone called oxytocin is released that intensifies and speeds up contractions. The increase in contractions causes more oxytocin to be released and the cycle goes on until the baby is born. The birth ends the release of oxytocin and ends the positive feedback mechanism. Know the role of insulin and glucagon in glucose homeostasis “Glucose homeostasis results from the balance between the balance of insulin and what alpha cell regulated molecule?” Glucagon Insulin and glucagon are antagonistic hormones that help maintain glucose homeostasis Insulin reduces blood glucose levels by promoting the cellular uptake of glucose, slowing glycogen breakdown in the liver, promoting fat storage Glucagon increases blood glucose levels by stimulating conversion of glycogen to glucose in the liver, stimulating breakdown of fat and protein into glucose Understand why Type I diabetes is most often seen in children It is an autoimmune disease of the pancreatic beta cells Know how a hormone such as ecdysone can induce both the development of the juvenile body and the adult body “The hormone ecdynsone stimulates what developmental stage in the absence of juvenile hormone?” Adult In insects, molting and development are controlled by a combination of hormones: A brain hormone stimulates release of ecdysone from the prothoracic glands Juvenile hormone promotes retention of larval characteristics Ecdysone promotes molting (in the presence of juvenile hormone) and development (in the absence of juvenile hormone) of adult characteristics Understand the primary differences between the anterior and posterior pituitary “The anterior pituitary differs primarily from the posterior as it is able to do in what regards to hormones?” Produce its own The posterior pituitary stores and secretes hormones that are made in the hypothalamus The anterior pituitary makes and releases hormones under regulation of the hypothalamus Why is oxytocin called the love drug? “The bond that occurs between a mother and her child is strengthened within the brain of the mother during nursing because of the effect of what positive feedback loop?” Oxytocin release after suckling Understand the concept of a hormone cascade pathway and why the anterior pituitary is a good example of this concept “The anterior pituitary is able to produce many hormones that further regulate other organs such as the thyroid. These hormones are controlled by the release of other hormones within the hypothalamus. This system is an example of what?” A cascade pathway Distinguish between tropic and non-tropic hormones, be able to classify a hormone into these categories “A tropic hormone regulates the function of what types of cells directly?” Endocrine Non-tropic hormones target non-endocrine tissues Non-tropic hormones produced by the anterior pituitary are Prolactin (PRL)- stimulates lactation in mammals Melanocyte-stimulating hormone (MSH)- skin pigmentation, fat metabolism A tropic hormone regulates the function of endocrine cells or glands The four strictly tropic hormones are Thyroid-stimulating hormone (TSH) Follicle-stimulating hormone (FSH) Luteinizing hormone (LH) Adrenocorticotropic hormone (ACTH) Chapter 27 Understand the way a cell establishes a resting membrane potential “The resting potential of the cell results from which of the following internal to external cellular gradients?” Higher external conc. of Na and lower external conc. of K Know in what location, inside or outside, concentration of Na and K are greater The concentration of K+ is greater inside the cell, while the concentration of Na+ is greater outside the cell “The flow of this molecule into the nerve cell leads to the depolarization of the membrane” Na “The flow of this molecule out of the nerve cell leads to the falling phase of the action potential” K Differentiate between a voltage gated ion pump and an ATP driven pump, know how these play roles in establishing membrane potentials of neurons “This voltage gated channel is responsible for the unidirectional flow of the action potential” Na Pump Understand the stages of the action potential At resting potential: Most voltage-gated Na+ and K+ channels are closed, but some K+ channels (not voltage-gated) are open When an action potential is generated, voltage-gated Na+ channels open first and Na+ flows into the cell During the rising phase, the threshold is crossed, and the membrane potential increases During the falling phase, voltage-gated Na+ channels become inactivated; voltage-gated K+ channels open, and K+ flows out of the cell Know what role the voltage gated pumps play in the term all or none depolarization Depolarization occurs if gated Na+ channels open and Na+ diffuses into the cell Understand how the voltage gated pumps allow for single directional flow of an action potential “This voltage gated channel is responsible for the unidirectional flow of the action potential” Na Pump Understand why the myelin sheath is important and how a squid is able to have axons with no myelin “The myelin sheath insulates axons to prevent the loss of electrical potential, how then does a squid have a nervous system that contains no myelin?” It compensates with wide axons Define the Nodes of Ranvier and their role in the propagation of the action potential “This property of the Nodes of Ranvier allows for the skipping of the action potential along the axon” It is not myelinated Chapter 34 Define ecology and the ecosystem Ecology is the scientific study of the interactions between organisms and the environment An ecosystem is the community of organisms in an area and the physical factors with which they interact Distinguish between populations, communities, individuals, and landscapes A population is a group of individuals of the same species living in an area A community is a group of populations of different species in an area A landscape is a mosaic of connected ecosystems The biosphere is the global ecosystem, the sum of all the planet’s ecosystems Distinguish between biotic and abiotic factors Biotic: predation, parasitism, competition, disease Abiotic: chemical factors (water, oxygen, salinity, pH, soil nutrients) , physical factors (temperature, light, soil structure, fire, moisture) Understand the effect that species transplant and invasive species may play on a local ecosystem Dispersal is movement of individuals away from centers of high population density or from their area of origin Dispersal contributes to global distribution of organisms Species transplants include organisms that are intentionally or accidentally relocated from their original distribution Species transplants can disrupt the communities or ecosystems to which they have been introduced Know what DDT is and what Rachel Carson did to change US policy DDT, the most powerful pesticide the world had ever known, exposed nature's vulnerability. Unlike most pesticides, whose effectiveness is limited to destroying one or two types of insects, DDT was capable of killing hundreds of different kinds at once.  Rachel Carson is credited with starting the modern environmental movement with the publication of Silent Spring in 1962 What two factors have the greatest impact on regional climate? Global climate patterns are determined largely by solar energy and the planet’s movement in space Be able to identify all terrestrial biomes based on a description of the biome Oligotrophic lakes are nutrient-poor and generally oxygen-rich Eutrophic lakes are nutrient-rich and often depleted of oxygen if ice covered in winter Rooted and floating aquatic plants live in the shallow and well-lighted littoral zone Water is too deep in the limnetic zone to support rooted aquatic plants; small drifting animals called zooplankton graze on the phytoplankton A wetland is a habitat that is inundated by water at least some of the time and that supports plants adapted to water-saturated soil Wetlands can develop in shallow basins, along flooded river banks, or on the coasts of large lakes and seas Streams and Rivers The most prominent physical characteristic of streams and rivers is current A diversity of fishes and invertebrates inhabit unpolluted rivers and streams Damming and flood control impair natural functioning of stream and river ecosystems Estuaries: a transition area between river and sea Salinity varies with the rise and fall of the tides Estuaries are nutrient rich and highly productive An abundant supply of food attracts marine invertebrates and fish Tropical Forest In tropical rain forests, rainfall is relatively constant, while in tropical dry forests precipitation is highly seasonal Tropical forests are vertically layered and competition for light is intense Tropical forests are home to millions of animal species, including an estimated 5–30 million still undescribed species of insects, spiders, and other arthropod Desert Precipitation is low and highly variable, generally less than 30 cm per year; deserts may be hot or cold Desert plants are adapted for heat and desiccation tolerance, water storage, and reduced leaf surface area Common desert animals include many kinds of snakes and lizards, scorpions, ants, beetles, migratory and resident birds, and seed-eating rodents; many are nocturnal Savanna Savanna precipitation and temperature are seasonal Grasses and forbs make up most of the ground cover Common inhabitants include insects and mammals such as wildebeests, zebras, lions, and hyenas Chaparral Chaparral climate is highly seasonal, with cool and rainy winters and hot dry summers The chaparral is dominated by shrubs, small trees, grasses, and herbs; many plants are adapted to fire and drought Animals include amphibians, birds and other reptiles, insects, small mammals and browsing mammals Temperate Grassland Temperate grasslands are found on many continents Winters are cold and dry, while summers are wet and hot The dominant plants, grasses and forbs, are adapted to droughts and fire Native mammals include large grazers and small burrowers Northern Coniferous Forest The northern coniferous forest, or taiga, extends across northern North America and Eurasia and is the largest terrestrial biome on Earth Winters are cold and long while summers may be hot The conical shape of conifers prevents too much snow from accumulating and breaking their branches Animals include migratory and resident birds, and large mammals Temperate Broadleaf Forest Winters are cool, while summers are hot and humid; significant precipitation falls year round as rain and snow A mature temperate broadleaf forest has vertical layers dominated by deciduous trees in the Northern Hemisphere and evergreen eucalyptus in Australia Mammals, birds, and insects make use of all vertical layers in the forest In the Northern Hemisphere, many mammals hibernate in the winter Tundra Tundra covers expansive areas of the Arctic; alpine tundra exists on high mountaintops at all latitudes Winters are long and cold while summers are relatively cool; precipitation varies Permafrost, a permanently frozen layer of soil, prevents water infiltration Vegetation is herbaceous (mosses, grasses, forbs, dwarf shrubs and trees, and lichen) and supports birds, grazers, and their predators Be able to distinguish between the layers of he aquatic biome The upper photic zone has sufficient light for photosynthesis Lower aphotic zone receives little light The organic and inorganic sediment at the bottom of all aquatic zones is called the benthic zone The communities of organisms in the benthic zone are collectively called the benthos Detritus, dead organic matter, falls from the productive surface water and is an important source of food The most extensive part of the ocean is the abyssal zone with a depth of 2,000 to 6,000 m Understand the effects of salt, water, sunlight, and temperature on the distribution of organisms Environmental temperature is an important factor in distribution of organisms because of its effects on biological processes Cells may freeze and rupture below 0°C, while most proteins denature above 45°C Mammals and birds expend energy to regulate their internal temperature Water availability in habitats is another important factor in species distribution Desert organisms exhibit adaptations for water conservation Salt concentration affects water balance of organisms through osmosis Few terrestrial organisms are adapted to high-salinity habitats Light intensity and quality affect photosynthesis Water absorbs light, thus in aquatic environments most photosynthesis occurs near the surface In deserts, high light levels increase temperature and can stress plants and animals Chapter 35 Define behavior on a biological level The basic biological definition here is an action carried out by muscles or glands under the control of the nervous system in response to the environment Behavior collectively is the sum of the animals responses to internal and external environmental cues Be able to identify a proximate and ultimate question for a given situation Proximate question address the immediate reason for a behavior Proximate Causes define how a stimuli causes an response in the organism An important proximate question involves how behavior develops during the life span of an organism Ultimate Questions address why a particular behavior occurred Ultimate Causes are evolutionary explanations, they lie in the adaptive value of the behavior Understand what role FAPs played in the understanding of innate behavior Innate behavior is behavior that is under strong genetic control and is performed the same way in all individuals of the species This subject was studied by looking at fixed action patterns: an unchangeable series of actions triggered by a specific stimulus Be able to distinguish between a genetically controlled behavior and an environmentally driven behavior Experiments in drosophila have lead to a number of identified genes that control mating and courtship Some genes control sexual differentiation, some genes control courtship Genes are regulated by environmental stimulus as well as through inherited mechanisms What is epigenetics? In mice the release of serotonin is induced by maternal licking, this results in the prevention of early methylation of the GR regulatory region Be able to distinguish between the 6 major forms of learning given examples Habituation: The simplest form of learning is really just an ignored stimuli An animal will learn to ignore a repeated stimulus that conveys little or no information Habituation may increase fitness by allowing an animal’s nervous system to focus on stimuli that matter Imprinting: Learning that is limited to a certain time period in an animals life The limited time is termed the sensitive period Geese at a young age will attach themselves to the object that is close by making noise and moving. Salmon are imprinted at birth with the unique chemical signature of their home stream Operation Migration: Endangered species pose a special problem when parents are not around to imprint behavior While animals will imprint on any species, many imprinting species will only mate with the species they imprint with Two protected sites in Wisconsin and Florida are setup as migratory targets for the whooping crane. Spatial Learning: Moving in a directional way enables animals to avoid predators, migrate to favorable environments, obtain food, and find mates or nests Spatial learning involves the establishment of memories of landmarks in the environment to home in on a specific location Movement of those landmarks by a secondary organism or event can confuse these species Migration Patterns: Many animals move from one part of the world on a seasonal basis, like the gray whale Gray whales stay close to the coast and use a behavior known as spyhopping to obtain visual reference points on land Whales may also use land marks under the ocean or magnetic cues This phenomenon is known as taxis, a response directed towards or away from a stimulus Trial and Error Learning: Associative learning is the ability to associate one environmental feature with another. In trial and error learning an animal learns to associate one of its own behaviors with a positive or negative effect Events associated with positive behavior are reinforced, this relies heavily on neurochemical interaction that form memories Social learning: Learning by the observation of the behaviors of others Predators often learn their skills by observing their mothers at a young age Vervet monkeys produce threat specific calls that lead to specific responses, these responses improve over time as associative learning is mixed in Problem Solving: Animals capable of cognition practice problem solving learning Cognition is the process carried out by the nervous system that perceives, stores, and integrates gathered information Problem solving is the process of applying past experience to overcome obstacles in novel situations Understand how the grey whale is able to make its yearly migration Many animals move from one part of the world on a seasonal basis, like the gray whale Gray whales stay close to the coast and use a behavior known as spyhopping to obtain visual reference points on land Whales may also use land marks under the ocean or magnetic cues This phenomenon is known as taxis, a response directed towards or away from a stimulus Understand the evolutionary goals of learning and the role that natural selection plays in foraging Learning is required for an animal to survive long enough to reproduce Remember it is the evolutionary goal to pass genetic information to the next generation Natural selection will refine behaviors that enhance the efficiency of feeding The behavior of an animal that includes searching, recognizing, capturing, and eating food is termed foraging Understand the basic underlying themes of the optimal foraging theory There are always trade offs in the energy spent gaining food and the energy produced from feeding The optimal foraging theory is a mathematical expression of a behavior that optimizes energy gain and minimizes energy expense and risk Wagtails (bird species) in an environment will favor medium size prey as a trade off between energy gained and energy expended Understand what communication is and what makes it effective within a community of animals A signal is a stimulus that is transmitted from one animal to another The sending, reception, and response constitutes the concept of communication Signals are optimized to the environment. A good signal can be seen, smelled, heard, or felt by other members of the species Be able to identify the most successful mating system given characteristics of a species and its offspring Mating is not the final step in reproductive success, offspring themselves must survive long enough to reproduce Animal mating systems fall into three categories, promiscuous, monogamous, and polygamous Understand the advantages and disadvantages of territories A territory is an area, usually a fixed location, where one or more individuals defends from other individuals of the same species. The size of the territory will vary based on the needs of the species The advantages of a territory are balanced by the cost of defending that territory. Understand how a dominance hierarchy is established and the role that altruism plays in community evolution and survival A ranking of individuals within a social group based on social interactions These hierarchies are established by agonistic behaviors and are often not challenged once established Reproductive success of the alphas within a species is often reinforced leading to a fitter species Altruism: Behavior that reduces the fitness of an individual while increasing the fitness of others in the population How is the prisoners dilemma an example of altruism? The defense of the hive is one example of many in nature Altruism is most seen when there are offspring that are found within the community The fitness of the individuals genes may be increased if the individual sacrifices their personal fitness Maximizing the fitness of similar of the same genes is the hallmark of inclusive fitness Natural selection that favors altruistic behavior involving relatives is termed kin selection Chapter 37 Define a biological community A biological community is an assemblage of populations of various species living close enough for potential interaction Understand the positive and negative effects of the various forms of interspecific interactions Ecologists call relationships between species in a community interspecific interactions Examples are competition, predation, herbivory, and symbiosis (parasitism, mutualism, and commensalism) Interspecific interactions can affect the survival and reproduction of each species, and the effects can be summarized as positive (+), negative (–), or no effect (0) Interspecific competition (–/– interaction) occurs when species compete for a resource in short supply Strong competition can lead to competitive exclusion, local elimination of a competing species The competitive exclusion principle states that two species competing for the same limiting resources cannot coexist in the same place The total of a species’ use of biotic and abiotic resources is called the species’ ecological niche An ecological niche can also be thought of as an organism’s ecological role Ecologically similar species can coexist in a community if there are one or more significant differences in their niches Resource partitioning is differentiation of ecological niches, enabling similar species to coexist in a community As a result of competition, a species’ fundamental niche may differ from its realized niche Predation (+/– interaction) refers to interaction where one species, the predator, kills and eats the other, the prey Herbivory (+/– interaction) refers to an interaction in which an herbivore eats parts of a plant or alga It has led to evolution of plant mechanical and chemical defenses and adaptations by herbivores Symbiosis is a relationship where two or more species live in direct and intimate contact with one another In parasitism (+/– interaction), one organism, the parasite, derives nourishment from another organism, its host, which is harmed in the process Parasites that live within the body of their host are called endoparasites; parasites that live on the external surface of a host are ectoparasites Many parasites have a complex life cycle involving a number of hosts Some parasites change the behavior of the host to increase their own fitness Mutualistic symbiosis, or mutualism (+/+ interaction), is an interspecific interaction that benefits both species A mutualism can be Obligate, where one species cannot survive without the other, Facultative, where both species can survive alone In commensalism (+/0 interaction), one species benefits and the other is apparently unaffected Commensal interactions are hard to document in nature because any close association likely affects both species Know the importance of variation in biological niches for the survival and coexistence of various species within the same community Resource partitioning is differentiation of ecological niches, enabling similar species to coexist in a community Distinguish between realized and fundamental niches Fundamental niche is the entire set of conditions under which an animal (population, species) can survive and reproduce itself.  Realized niche is the set of conditions actually used by given animal (pop, species), after interactions with other species (predation and especially competition) have been taken into account. Understand how character displacement allows for species to live in a sympatric manner Character displacement is a tendency for characteristics to be more divergent in sympatric populations of two species than in allopatric populations of the same two species Allopatric: Geographically separate Sympatric: Geographically overlapping An example is variation in beak size between populations of two species of Galápagos finches Know the various adaptations prey have made to avoid predators Some feeding adaptations of predators are claws, teeth, fangs, stingers, and poison Morphological & physiological defense adaptations: Cryptic coloration, or camouflage, makes prey difficult to spot Animals with effective chemical defense often exhibit bright warning coloration, called aposematic coloration Behavioral defenses include hiding, fleeing, forming herds or schools, self-defense, and alarm calls In Batesian mimicry, a palatable or harmless species mimics an unpalatable or harmful model In Müllerian mimicry, two or more unpalatable species resemble each other Understand the two components of diversity: richness and abundance Species diversity of a community is the variety of organisms that make up the community Species richness is the total number of different species in the community Relative abundance is the proportion each species represents of the total individuals in the community Distinguish between the characteristics of dominant species, keystone species, foundation species, and invasive species. Invasive species, typically introduced to a new environment by humans, often lack predators or disease Dominant species are those that are most abundant or have the highest biomass Biomass is the total mass of all individuals in a population Dominant species exert powerful control over the occurrence and distribution of other species One hypothesis suggests that dominant species are most competitive in exploiting resources Another hypothesis is that they are most successful at avoiding predators Keystone species exert strong control on a community by their ecological roles, or niches In contrast to dominant species, they are not necessarily abundant in a community Understand how a bottom-up model differs from the top-down model The bottom-up model of community organization proposes a unidirectional influence from lower to higher trophic levels In this case, presence or absence of mineral nutrients determines community structure, including abundance of primary producers The top-down model, also called the trophic cascade model, proposes that control comes from the trophic level above In this case, predators control herbivores, which in turn control primary producers Know the importance of a disturbance in the diversity of a community A disturbance is an event that changes a community, removes organisms from it, and alters resource availability Fire is a significant disturbance in most terrestrial ecosystems It is often a necessity in some communities The intermediate disturbance hypothesis suggests that moderate levels of disturbance can foster greater diversity than either high or low levels of disturbance High levels of disturbance exclude many slow-growing species Low levels of disturbance allow dominant species to exclude less competitive species Understand the various abiotic factors that lead to species richness Size of habitat, spatial patchiness, harshness of habitat, predictability of change in the habitat, disturbances in a habitat, isolation of habitat Be able to read a species-area curve and identify the equilibrium number Chapter 38 Know the greatest extinction threat on the planet Humans are rapidly pushing many species toward extinction Understand the various sciences involved in conservation biology Conservation biology, which seeks to preserve life, integrates several fields: Ecology, Physiology, Molecular biology, Genetics, Evolutionary biology Restoration ecology applies ecological principles to return degraded ecosystems to conditions as similar as possible to their natural state Understand how the destruction of an ecosystem leads to the extinction of communities In almost all cases, habitat fragmentation and destruction lead to loss of biodiversity In Wisconsin, prairie occupies <0.1% of its original area About 93% of coral reefs have been damaged by human activities Overexploitation is human harvesting of wild plants or animals at rates exceeding the ability of populations of those species to rebound Overexploitation by the fishing industry has greatly reduced populations of some game fish, such as bluefin tuna Distinguish between the three levels of biodiversity Genetic diversity:  the total number of genetic characteristics in the genetic makeup of a species Species diversity: the number of different species that are represented in a given community (a dataset). Ecosystem diversity: refers to the variety of ecosystems in a given place. Within any broader landscape there is a mosaic of interconnected ecosystems.  Be able to identify some economic and scientific benefits to having significant biodiversity on the planet Distinguish between endangered and threatened species An endangered species is “in danger of becoming extinct throughout all or a significant portion of its range” A threatened species is likely to become endangered in the foreseeable future Define the three threats to biodiversity Habitat destruction Introduced species are those that humans move from native locations to new geographic regions Without their native predators, parasites, and pathogens, introduced species may spread rapidly Introduced species that gain a foothold in a new habitat usually disrupt their adopted community Sometimes humans introduce species by accident, as in case of the brown tree snake arriving in Guam as a cargo ship “stowaway” Overexploitation is human harvesting of wild plants or animals at rates exceeding the ability of populations of those species to rebound Overexploitation by the fishing industry has greatly reduced populations of some game fish, such as blue fin tuna Understand the effects of invasive species and how they may endanger species diversity An invasive species can be any kind of living organism—an amphibian (like the cane toad pictured left), plant, insect, fish, fungus, bacteria, or even an organism's seeds or eggs—that is not native to an ecosystem and which causes harm. They can harm the environment, the economy or even, human health. Define the small population approach and understand the extinction vortex A small population is prone to positive-feedback loops that draw it down an extinction vortex The key factor driving the extinction vortex is loss of the genetic variation necessary to enable evolutionary responses to environmental change Distinguish between the MVP and the effective population size Minimum viable population (MVP) is the minimum population size at which a species can survive The MVP depends on factors that affect a population’s chances for survival over a particular time A meaningful estimate of MVP requires determining the effective population size, which is based on the population’s breeding potential Know why the declining population approach is more experimental intensive The declining-population approach focuses on threatened and endangered populations that show a downward trend, regardless of population size Emphasizes the environmental factors that caused a population to decline The declining-population approach involves several steps: Confirm that the population is in decline Study the species’ natural history Develop hypotheses for all possible causes of decline Test the hypotheses in order of likeliness Apply the results of the diagnosis to manage for recovery Understand how a landscape effects community structure and the importance of the edges in a landscape The boundaries, or edges, between ecosystems are defining features of landscapes Some species take advantage of edge communities to access resources from both adjacent areas Define fragmentation and understand how a movement corridor can help correct some of the problems brought about by fragmentation Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment(habitat), causing population fragmentation and ecosystem decay. Habitat fragmentation can be caused by geological processes that slowly alter the layout of the physical environment (suspected of being one of the major causes of speciation), or by human activity such as land conversion, which can alter the environment much faster and causes extinctions of many species. A movement corridor is a narrow strip of quality habitat connecting otherwise isolated patches Movement corridors promote dispersal and help sustain populations In areas of heavy human use, artificial corridors are sometimes constructed Understand how a natural reserve works and why it is important to have multiple small reserves rather than one large reserve. Nature reserves are biodiversity islands in a sea of habitat degraded by human activity Nature reserves must consider disturbances as a functional component of all ecosystems One argument for extensive reserves is that large, far-ranging animals with low-density populations require extensive habitats Smaller reserves may be more realistic, and may slow the spread of disease throughout a population The zoned reserve model recognizes that conservation often involves working in landscapes that are largely human dominated A zoned reserve includes relatively undisturbed areas and the modified areas that surround them and that serve as buffer zones Zoned reserves are often established as “conservation areas” Costa Rica has become a world leader in establishing zoned reserves Understand the importance of restoration ecology and define the two approaches, bioremediation and biological augmentation Given enough time, biological communities can recover from many types of disturbances Restoration ecology seeks to initiate or speed up the recovery of degraded ecosystems A basic assumption of restoration ecology is that most environmental damage is reversible Two key strategies are bioremediation and augmentation of ecosystem processes Bioremediation is the use of living organisms to detoxify ecosystems The organisms most often used are prokaryotes, fungi, or plants These organisms can take up, and sometimes metabolize, toxic molecules Biological augmentation uses organisms to add essential materials to a degraded ecosystem For example, nitrogen-fixing plants can increase the available nitrogen in soil The newness and complexity of restoration ecology require that ecologists consider alternative solutions and adjust approaches based on experience Be able to identify sustainable development given a choice between some non sustainable examples and one sustainable example Sustainable development is development that meets the needs of people today without limiting the ability of future generations to meet their needs The goal of the Sustainable Biosphere Initiative is to define and acquire basic ecological information for responsible development, management, and conservation of Earth’s resources Sustainable development requires connections between life sciences, social sciences, economics, and humanities