8/13/2019 Bio Midyear Study Guide Answers

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Bio Study Guide Answers -Jerry Han ECOLOGY 1. What are abiotic factors? What are biotic factors? Give three examples of each.  -Abiotic factors are nonliving factors that affect living things. --Natural disasters (Floods, earthquakes, tornadoes, etc.) --Weather  --Habitat -Biotic factors are living things that affect other living things --Animals --Bacteria --Plants 2. What are the six levels of ecological organization? O, P, C, E, B, B -Organism -Population -Community -Ecosystem -Biome -Biosphere (The order is from smallest to largest) 3. What is meant by an organism’s niche? Describe the niche of two differentanimals. - An organism’s niche is the role it playing that specific ecosystem. --In a swamp biome, a cattail’s niche would be providing a home for  some organisms, aswell as producing energy for the animals to obtain by consuming it. --In an ocean biome, a shark’s niche would be to control the amount of smaller fish thereare in the ocean. 4. How do autotrophs differ from heterotrophs? Give three examples of each. -Autotrophs have the ability to produce their own energy (ATP), without the help of otherorganisms. --Cattails --Trees --Flowers -Heterotrophs cannot produce their own energy, and must obtain it through consumption ofother organisms. --Caterpillars --Lions --Humans 5. How does photosynthesis differ from chemosynthesis? How are they alike? -Photosynthesis is when a producer uses the sun to produce energy -Chemosynthesis is when a producer uses chemical reactions to produce energy --These two processes are alike because they both use a non-heterotrophic way to produceenergy. Furthermore, these processes can only be used by producers. 6. How does primary succession differ from secondary succession? -Primary succession is the development of life on something that previously never had life init before, such as Lichen on a cooled off lava flow. 

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-Secondary succession is the development of life on a previously disturbed or destroyedhabitat, such as a fern growth after a forest fire. 7. Describe how energy flows through an ecosystem. How does this compare to howmatter moves through an ecosystem? -Energy flows through an ecosystem through food. What an animal eats is how it gets itsenergy. --I would take the time to explain this, but I’ll just “Write” an energy pyramid instead, for ithink that would be a little easier to comprehend. ---Producer(100% Energy) -> Primary Consumer(10% Energy) -> Secondary Consumer(1%Energy) -> Tertiary Consumer(0.1% Energy) ----Explanation: Due to the fact that an organism needs energy for bodily functions, theamount of energy one organism obtains from eating another organism is only 10% of what ithad inside its body, because the other 90% was used for bodily functions, therefore only10% was saved in the organism for later use. This also explains why there are so littleorganisms higher up in the food chain. 8. How does a food chain differ from a food web? Give an example of each. -A food chain is a simple map that only shows one path of predator prey relations. Ex. Plant 

-> Primary Consumer  -> Secondary Consumer  -> Tertiary Consumer  -A food web is a complex map shows the whole network of predator prey relations. Ex. (The V’s represent predator -prey relationships) P P P P P (Producer) V V V V1 1 1 1 (Primary Consumer) V V V 2 2 2 (Secondary Consumer) V V 3 3 (Tertiary Consumer) 

-The amount of energy in an energy pyramid is pretty close to the amount of mass in anenergy pyramid due to the fact that energy gets more scarce the higher up an organism is in

the pyramid. This means, of course, that there are more producers that primary consumers,more primary than secondary, etc. THEREFORE, THE TOTAL MASS ON THE HIGHERLEVELS OF THE PYRAMID WOULD BE LOWER THAN THE AMOUNT OFPRODUCERS. 9. What are the three types of ecological pyramids, and how do they differ? -The pyramid of Energy -The pyramid of Mass -The pyramid of Numbers (Pretty self explanatory. being the lazy person I am, I’m not going to explain anything i thinkof as simple. Keep that in mind when reading this.) 10. What is biomagnification, and why is it important to ecological systems? -Biomagnification is the concentration of toxins in an organism depending on its level in thefood web. Ex. Mercury in fish: Plankton picks up tiny amounts of mercury in the water,smaller fish eat plankton, which in turn get eaten by bigger fish. The bigger fish, because itneeds to eat many fish to get as much energy as it needs, eats multiple little fish, resultingin a concentration of the mercury from all the small fish, making the amount higher in thebigger fish. -- I can’t find a reason that this is important, from a biological standpoint, except for that weshould really stop polluting the oceans, but we all know thats not going to stop for a longtime. 

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11. Draw and label each of the following cycles: water, nitrogen, carbon, andphosphorous -Below are the links to these cycles. I’m not going to draw this out. -Water- http://www.enchantedlearning.com/wgifs/Watercycle.GIF -Nitrogen-http://img.bhs4.com/47/4/4747ca1353672c2853d351e4e2c3aac4af6f17fb_large.jpg -Carbon- http://eo.ucar.edu/kids/green/images/carboncycle_sm.jpg -Phosphorus- http://www.enviroliteracy.org/images/page-spec//phoscycle2.gif  12. What are the three types of symbiosis? Give three examples of each. -Parasitism- One party benefits, while the other suffers --tapeworm + host --tubeworm +host --leech + host -Commensalism- One party benefits, and the other does not benefit or suffer  --bird + tree --lichen + tree --spider + tree -Mutualism- Both parties benefit --bees + flowers --bacteria + human (bacteria live inside human, and in turn, helps digest the human’s food) --oxpecker + large mammal (an oxpecker is a type of bird that helps keep other mammalsclean by digging out parasites on them and eating them. in this situation, the bird gets food,and the mammal avoids a potentially serious threat.)(used this because I couldn’t think of abetter one.) 13. How does biodiversity influence the stability of an ecosystem? How do invasivespecies affect biodiversity? -Biodiversity makes the stability of an ecosystem stronger, because the more niches thatare filled, the less flaws that ecosystem has. --Invasive species affect biodiversity because of they take over and out compete a native

species’ niche, and because there are no predators to control the new species, itoverpopulates. Meanwhile, the species it out competes dies off, and that impacts all speciesthat depended on it. 14.What are the advantages of sexual reproduction? Asexual reproduction? -Sexual reproduction takes time and energy, but has a lot of sexual diversity. -Asexual reproduction is quick and takes little energy, but the offspring is basically identicalto the parent. 15. How does r-strategy differ from K-strategy? Which type are humans? -r-strategy- Creates many offspring early in life, leave and hope at least some of themsurvive. Quantity. -K-strategy- Creates little offspring later in life, raise and nurture them, protect them.

Quality. 16. How does exponential growth differ from logistic growth? Graph and label each.Which curve does the human population follow? -Exponential growth is the supposed growth rate without a Carrying Capacity(The amount ofthe same organism a biome can handle due to limited resources.) -Logistic growth is the growth rate of a population taking into account the carrying capacityof a biome. --Once again, I refuse to draw this on a computer, so here is the link for both charts-http://www2.estrellamountain.edu/faculty/farabee/BIOBK/expgrowth.gif  

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17. How do density-dependent limiting factors differ from density-independentlimiting factors? Give two examples of each. -Density dependent limiting factors are things that hinder a population with the help of theamount there is. -- Virus- The closer together the organisms are, the more it will spread. -- Food- The more of an organism there is, the less food is readily available -Density independent limiting factors are things that hinder a population regardless of howmany of that organism there are. -- Natural Disasters -- Weather  18. What is meant by “the tragedy of the commons?” Give a r eal world example. - Tragedy of the commons is a process where an overexploited resource is used until whatit yields is depleted. Ex. (Based off this video)- A rancher find an unclaimed field, and bringshis cows to graze. In turn, other ranchers bring their cows to graze as well, depleting theamount of grass. If, say, rancher A realizes that the field is going to be ruined if he doesn’tstop grazing, and stops taking his cows there, others will continue to graze and ruin thepasture without rancher A. then, rancher B realises that the pasture is going to be ruined as

well, and tries to get all the other ranchers to stop. But, since the pasture isn’t private, hecan’t do anything to stop them, and the field will gradually be depleted. --Video- https://www.youtube.com/watch?v=MLirNeu-A8I Chemistry of life will be done when I feel like it (Don’t get your hopes up, I might not do it atall.)