Bio UA - Ch 1 Updated PDF

Chapter 1: Energy Transfer in the Biosphere Chapter 2: Cycles of Matter Unit A: Energy and Matter Exchange in the Biosphere  Chapter 1: Energy Transfer in the Biosphere Terms to Know cellular : deco...

Chapter 1: Energy Transfer in the Biosphere Chapter 2: Cycles of Matter Unit A: Energy and Matter Exchange in the Biosphere  Chapter 1: Energy Transfer in the Biosphere Terms to Know cellular : decomposers respiration trophic levels photosynthesis food chain producers food web consumers biomass albedo pyramid of numbers chemosynthesis pyramid of biomass primary pyramid of energy consumers biomagnification The Study of Ecology Ecology: the study of relationships between living things (organisms) and their non-living surroundings (the environment). Ecology” is based on a greek “ word that means “oikos” or household Term coined by Ernst Haeckel  ecology encompasse s… Biotic factors: living components and processes of an ecosystem. E.g. photosynthesis, cellular respiration, fermentation, growth, reproduction, parasitism, disease, competition, and population density. Abiotic factors: nonliving components of an Dynamic equilibrium: the living (biotic) and nonliving (abiotic) components form a self-regulating system through which energy and matter are transferred. Birth, growth, production, breathing, consumption, movement, death, and decomposition occur continuously and simultaneously, forming a balance biotic and abiotic factors in this ecosystem  Biosphere: all of the areas of Earth that are inhabited by and support life Consists of: The atmosphere is the gaseous part of Earth, concentrated mainly within 10 km of Earth’s surface, but also extending hundreds of21% kilometers oxygen;higher. Composition78% – nitrogen; 0.934% argon; 0.036% other  Lithosphere (aka geosphere) - solid, mainly rocky part of Earth Hydrosphere - all of the Earth’s water (in all three states) including surface water, groundwater and Systems may be classified into three types: 1. Open system: energy and matter are exchanged between the system and its surroundings (e.g. tree). 2. Closed system: energy is exchanged but matter is not (e.g. Earth) 3. Isolated system: matter and energy Where does Earth fit?  The Earth is essentially a closed system Earth absorbs solar energy and thermal energy is radiated from the Earth back into space matter is not exchanged with earth’s surroundings. Matter cycles within Earth. Biosphere All organisms need energy to grow, maintain body processes, reproduce, and possibly for movement. The majority of energy on Earth originates from the Sun. Producers such as plants, algae, and some bacteria are able to convert energy from the Sun into energy-rich carbohydrates in a process called... ??  ALL living things (producers & consumers) convert carbohydrates into useable energy through cellular respiration or, in some cases, fermentation (if oxygen not available) Although the processes are very different, the overall equations for photosynthesi s and cellular Producers = Autotrophs Capable of producing their own food. Photoautotrophs use energy from the Sun to produce chemical energy in the form of carbohydrates. Examples: plants, phytoplankton, some bacteria, and some protists. Volvox colony (protists) Diatoms (phytoplankt on)  About 1-2% of incoming solar energy is absorbed by producers on the land and in lakes, rivers, and oceans That’s a to beamount small used inof photosynthesis. solar energy absorbed by producers – but generate 150-200 billion tonnes of organic matter/year and sustain all life on earth! Albedo describes the amount of energy that a surface will reflect. ➔ Light coloured surfaces (snow, ice) and thick cloud cover have a HIGH albedo (80 – 90%) – hence they reflect solar energy ➔ dark surfaces (forest canopy) and water have LOW albedos (about 25% or less) – hence they absorb solar energy. ➔ Impacts amount of solar energy available for photoautotrophs in an ecosystem Energy for Life in the Deep Ocean Chemoautotrophs, or chemosynthetic producers, live near deep-sea vents that release extremely hot water containing hydrogen sulfide. Video Link - Hydrothermal Vent s Solar energy is not able to reach the deep dark depths, so… Bacteria live inside the tissues of tubeworms and perform chemosynthesis. Bacteria split inorganic molecules, such as hydrogen sulfide, to release energy. Chemosynthetic producers can also be found in soil, hot springs, salty lakes, and Deep Sea Hydrothermal Vent Communities  Chemosynthesis: How is process above How is process different from similar to photosynthesis? photosynthesis? Consumers = Heterotrophs Must consume autotrophs or other heterotrophs for energy. Herbivores only consume producers. Carnivores primarily consume other animals. Omnivores consume both plants and animals. Parasites live on or in a host organism and causes damage to the host.  Levels----------- Primary consumers (1º C) eat producers directly Secondary consumers (2º C) eat primary consumer Tertiary consumers (3º C) – top level consumer Quaternary consumers (4º C) – top level consumer *Not all food chains, webs will have 4 consumers ⭘  Decomposers obtain energy by digesting than absorbing leftover dead matter and waste (called detritus). E.g. fungi, bacteria. crucial for returning inorganic matter to the soil, air, and water to be used again  Detritivores consume small particles of detritus. E.g. earthworms, dung flies, woodlice slugs, sea stars & cucumbers. Scavengers consume large particles of detritus. E.g. vultures, raccoons, ants. Day 1 - to here The Fate of Energy in the Biosphere (Thermodynamics) 1.First law of thermodynamics: energy cannot be created or destroyed; it can only be converted from one form to another. 2.Second law of thermodynamics: no energy transformation is 100% efficient. Q. What is the most common form of “wasted” energy in an inefficient system? Recall that Earth is a CLOSED system Matter cycles between the various components within the biosphere (but is not exchanged between Earth and its surroundings). Energy does NOT cycle – solar energy enters atmosphere, some is absorbed and some is reflected/re-radiated back into space With each conversion that happens on Earth, some energy is “wasted” or “lost”, usually as thermal energy that radiates back into space. Some of the thermal energy is useful e.g. cellular respiration – energy stored in glucose converted to ATP, thermal energy also produced as waste product - but many organisms use this energy to maintain internal temp The SUN is the ultimate source of energy for all living things! Energy FLOWS Matter Things to look at following class: ❏ Review the student notes (to p.7) ❏ Thought Lab handout - Energy fluctuations assignment ❏ Textbook assignment: read pages 8-15, and answer questions 1-8 on p. 15 - submit via GC as a photo of your paperwork, or a google doc ❏ Did you answer the First Day Survey the helps your teacher get to know you?  Transferred in the Biosphere What can you remembe r about these three processes ?  How does energy transfer within the biospher e? Radiation it is transmitted as electromagnetic waves that make up the electromagnetic spectrum.  When radiation energy encounters particles of matter, it may be reflected or absorbed. If the radiation is absorbed, the kinetic energy of the particles will increase resulting in a temperature increase. Substances that are at a higher temperature than their surroundings will transfer thermal energy to their surroundings or re-emit the energy as infrared radiation. Conduction is the transfer of thermal energy through direct contact between the particles of a substance, without moving the particles to a new location. Usually occurs in solids and liquids. Convection is the transfer of thermal energy through the movement of particles from one location to another. ➔ Usually occurs in fluids – i.e. liquids and gases. ➔ During convection, the movement of particles forms a Trophic Levels – How energy is transferred between Ecosystem living things!= all the organisms that live in a particular environment and the physical environment (e.g. water, minerals, sunlight) in an area. Together, the living (biotic) and nonliving (abiotic) components form a self-regulating system through which energy and matter are transferred Birth, growth, production, breathing, consumption, movement (immigration, emigration), death, and decomposition occur continuously and simultaneously. A state of dynamic equilibrium exists A trophic level in an ecosystem is a feeding level at which matter and energy are transferred. FIRST trophic level = Producers (photosynthetic & chemosynthetic organisms). SECOND trophic level = 1ºconsumers (usually herbivores) THIRD trophic level = 2º C (secondary) Video Link - Trophic Lev FOURTH trophic level = 3º C (tertiary) els (3:15 min) FIFTH trophic level (if there is one) = 4º C (quaternary) Decomposers are consumers that feed at all trophic levels. There is always less energy available at higher trophic levels, thus fewer organisms at higher levels. NOTE: Some consumers can occupy more than one trophic level in an ecosystem e.g. humans can be primary consumer (eat broccoli) and secondary consumer (eat fish)  Figure 1.11 A grizzly bear transfers energy to waste products and to the environment, as heat, during cellular respiration. Although the energy values are estimates, very little energy (6 kJ) is transferred to the bear for growth and maintenance. Cellular respiration enables the bear to access the energy content in food so that it  There is always less energy available at higher trophic levels, thus fewer organisms at the higher levels. Q. Why do you think there is less energy as Rule of About 10% of the energy 10 available at one trophic level is transferred to the next trophic ➔ The remaining 90% level of energy is used within a trophic for various life processes, such as… Cell respiration Reproduction Growth & repair Regulation (responding to Movement environment) Metabolism (breathing, digesting, ➔ Some of that 90% is also “lost” or “wasted” as thermal energy eliminating etc) ➔ SO….energy availability limits the number of organisms at each trophic level in an ecosystem as well as the number of trophic levels there are! Video Link - Food Webs & Energy Pyramids (Amoeba Si  DO NOW! 10 J Calculate energy 100 transfer J 1 000 J NOTE! Only 1-2% of solar energy is usable, so start with 10 000 J here 1 000 000 J (1%, so move the decimal incoming solar point 2 to left)  Food Chains and Food AWebs food chain is a model that shows the linear pathway through which energy is transferred from one trophic level to another Represent a simple, single pathway for the flow of energy in a complex ecosystem DO NOW! Draw a realistic food chain with at least four organisms Label P, 1º C, 2º C, 3º C etc. What’s the problem with a meat- based diet? Food Webs (many food chains)  A food web is a more realistic model of energy transfer in an ecosystem that shows the connections among food chains. Food webs better represent feeding relationships in an ecosystem, and how energy is transferred An organism can be at more than one trophic level, depending on which pathway (i.e. food chain) you follow within a food web Can be kind of complicate d.....  Terrestri al DO NOW! Food Web Trace two different pathways of energy flow in the food web. Label the producers, Deep-Sea Vent Food Web  weave! Woodla nd - Lake Food Web  Arctic Food Web  Arctic Food Web Biomagnification the tendency for toxins to build-up in living organisms and accumulate faster than they can be excreted or broken down. Toxins tend to be present in higher Video Link - concentrations in higherBiomagnification trophic levels due to - Amoeba Sister s Notes: Notes: Peregrine Falcon:DDT accumulates in top predators Eggs not strong enough to support chick until time to hatch... Therefore cannot reproduce. Video Link - Biomagnification - Peregrine F alcon and DDT DDT cont... DDT also affects human populations found in breast milk came from sprayed crops and animals that ate crops banned in Canada and US in 1970’s not banned in other areas - Mexico, Central America continues to be produced as a cheap pesticide in poorer nations Biomagnification – other examples Mercury in aquatic systems PCBs Video Link - Energy Flow in E cosystems (7 min) Ecological Pyramids NUMBERS Each bar of the pyramid represents a different trophic level and its width represents the relative numbers of organisms as that level. Useful way to estimate the amount of energy at each trophic level, but it does not take into account the SIZE of individual organisms. Therefore… Pyramids can be upright or inverted. Grassland / Prairie ecosystem Upright pyramid – producer level bar is the widest Forest ecosystem Inverted pyramid – number of producers is less than the number of 1º consumers A few BIG trees can support many insects Aquatic/Ocean ecosystem Upright or inverted? BIOMASS The width of each bar represents the amount of biomass at each trophic level. Biomass = dry mass of living or once- living organisms per unit area (e.g. grams/m2, kg/m2). Useful way to estimate the amount of energy in an ecosystem. Pyramids can be upright or inverted.  Bog ecosystem Upright or inverted?  Pyramids of biomass can be inverted in aquatic ecosystems if phytoplankton (producer) are consumed at a rate that equals their reproduction rate. 3. Pyramid of ENERGY The width of each bar represents the TOTAL amount of energy that is available in each trophic level (e.g. J, kJ, kJ/m2) Pyramids are always upright because there will always be less energy at higher trophic levels due to the laws of thermodynamics (namely the 2nd Law – no energy transformation is 100% efficient). Even if the producer level has less biomass than higher trophic levels (i.e. inverted), energy flow up the trophic levels will still follow the “Rule of 10” Figure 1.17 This pyramid of energy transfer shows 10 percent efficiency in energy transfer from one trophic level to the next. The rate of efficiency can vary from 5 to 20 percent. This assumes that 1 percent of solar energy is captured by primary > > > > > > ❏ Changes to one trophic level in a food chain or web will affect energy transfer in an ecosystem ❏ Affects survival of individual organisms and whole species – impacts biodiversity ❏ Changes in climate affect biodiversity – might change who is most fit to survive – which changes feeding relationships ❏ Changes in a food web provide important information about the health of an ecosystem and can also provide clues about climate change Cycles of Matter