Term
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Definition
| organs that carry out the commands of the Central Nervous System. most common is muscles. |
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Term
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Definition
*propel an organism through a typical pattern of beating. move by microtubules, which have a typical pattern of arrangement: 9 pair surrounding a central pair, dynein activity and claw-like arms*, lengthening and shortening drive flagella/cilia.
action of flagella is very similar/identical to that of cilia, only difference is less numbers present. |
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Term
| Uses of cilia/flagella other than moving |
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Definition
| feeding, locomotion, propel water past gills, keep respiratory passages clear, drive fluids into excretory tubes, propulsion of sperm. |
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Term
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Definition
| movement via psuedopodia. this movement is used in ameobas and some cells of higher animals. NOT FINISHED |
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Term
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Definition
| the rigid supports against which muscles pull to create directed movement. there are three types: hydrostatic skeletons, endoskeletons, and exoskeletons. |
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Term
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Definition
| consist of a volume of fluid enclosed in a body cavity surrounded by muscle. when muscles oriented in one direction (circular or horizontal) contract, the fluid-filled body cavity bulges out in the opposite direction. found in cnidarians, annelids, and other soft-bodied invertebrates. earthworms are a good example. they use muscles, hydrostatic skeleton, and setae to move. they alternately contract circular muscles (setae withdrawn) and longitudinal muscles (setae extended). circular muscles contract to stretch earthworm, longitudinal muscles contract to make segments wider. bristles help the widest parts of the body to hold firm against the substratum. *hydrostatic skeletons rely upon fluid pressure to keep body rigid, allowing muscle to push/pull against it* |
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Term
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Definition
| it is a hardened, rigid outer surface to which muscles can be attached. it is most advance in arthropods (insects). its ultimate functions are support against gravity and attachment for muscles. the insect exoskeleton is made of hardened plates of glucosamine, secreted by a layer of cells just below the exoskeleton, connected by elastic walls/tissues. the muscles are attached to the inner walls. the actual exoskeleton is non-cellular, made up of chitin, which can be very hard and layers the cuticle. |
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Term
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Definition
| it is an internal scaffolding on which muscles are attached to and pull against. composed primarily of two materials- bone and cartilage. cartilage is composed of widely spaced cells called chondrocytes. the chondrocytes produce and maintain the cartilagenous matrix, which consists mainly of protein (collagen) and carbs. bone is composed of living cells called osteocytes which lie within small lacunae (cavities in the bone). |
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Term
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Definition
| cancellous (spongy) and compact. cancellous is found at the ends of compact bones and has many cavities. compact bones are dense hollow cylinders surrounding a central cavity that contains bone marrow, where the cellular elements of the blood are made. |
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Term
| two vertebral skeletal systems |
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Definition
Axial skeleton: consists of the skull, spine, and ribs; as well as muscles involved with life function.
Appendicular skeleton: consists of the appendages and associated bones; muscles do work of moving the body. |
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Term
| 3 Ways of Joining of bones |
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Definition
1. Fused: skull
2. Ligaments: connect bone to bone
3. Tendons: connect bone to muscle |
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Term
| 3 different types of muscle |
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Definition
1. Skeletal: large, multinucleate, striated because of actin/myosin bands
2. Smooth: associated width internal organs and arteries
3. Cardiac: more branched than smooth muscle |
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Term
| General characteristics of all muscles |
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Definition
| contraction is active, elongation is passive |
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Term
| Antagonistic activity of skeletal muscles |
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Definition
| flexor muscles bend an appendage, extensor muscles relax an appendage. |
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Term
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Definition
| the skeletal muscle cells are called "muscle fibers". two main proteins are actin and myosin. there are bands in the striated muscle: I bands (low density), A bands (high density), H zone (moderate density), Z line. |
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Term
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Definition
| the contractile unit in skeletal muscle, a bunch of these make up a myofibril. each one is made of overlapping filaments of actin and myosin, which create a distinct banding pattern that is responsible for "striated" muscle, and attaches to a Z line. |
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Term
| Contraction results in structural changes |
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Definition
| note that: the sarcomere shortens, H zone and I band shrink, A band stays the same. |
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Term
| Ultrastructure of myofibrils |
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Definition
| *relaxation is accomplished by breaking all connections. contraction is begun by a nervous impulse; neurotransmitter is released at the neuromuscular junction- causes depolarization of the muscle membrane. |
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Term
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Definition
thick myosin is in A band, and H zone is strictly made up of myosin.
thin actin is in A band, and I band is strictly made up of actin.
contraction happens when actin slides together over myosin. |
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Term
| Sarcoplasmic Reticulum and T system |
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Definition
T system: a distribution system of tubules that descend into the muscle fiber cytoplasm and surround the muscle fibers. this system of "Transverse tubules" helps spread the action potential through the muscle. SR: a closed compartment surrounding every myofibril. calcium pumps in the SR take up Ca2+ ions from the sarcoplasm, so that when the muscle fiber is at rest there is a higher concentration of Ca2+ in the SR and a lower concentration in the sarcoplasm.
calcium ions are are responsible for electrical changes necessary to make muscle contract. however, calcium cannot make simultaneous contraction though. the sarcoplasmic reticulum and T system help with this process. contraction is stimulated by an influx of calcium ions across the membrane, through the T system and SR. relaxation involves active transport of calcium ions out of the muscle matrix and into the SR and T system. |
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Term
| Molecular Basis for muscle contraction |
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Definition
actin filaments is a helical arrangement of actin monomers. twisted around the actin helix are two strands of tropomyosin, which serves as a blocker to all sites where myosin can attach to actin. at regular intervals on the actin filament are globular proteins called troponin, made up of 3 subunits that serve as binding sites. one subunit binds actin, another binds tropomyosin, and another binds Ca2+.
at rest, the tropomyosin strands are blocking the actin-myosin binding sites. when Ca2+ is released into the sarcoplasm, it binds to troponin, changing the conformation of tropomyosin. the binding sites are now exposed, and actin-myosin bonds are formed. next the two filaments are pulled in opposite directions of each other (thanks to the myosin head), and the muscle fiber contracts. the muscle fiber returns to resting state when calcium pumps remove the Ca2+ ions from the sarcoplasm and tropomyosin goes back to its original blocking state. |
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Term
| Contraction is generated by a nervous impulse |
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Definition
| neurotransmitters are release at the neuromuscular junction, causing depolarization of the pre-synaptic membrane. Na+ comes in, causing voltage-gated Ca2+ channels to open. Ca2+ enters the cells and triggers the vesicles to release ACh into the synaptic cleft. ACh binds to receptors on postsynaptic membrane, causing the depolarization of the postsynaptic membrane via Na+ rushing in once again. this spreading depolarization fires an action potential along the postsynaptic membrane. the action potential then travels down through T tubules, causing the release of Ca2+ stored in the SR. this release of Ca2+ stimulates muscle contraction because it binds to troponin, shifting the position of tropomyosin and allowing myosin to bind to actin. ATP hydrolysis causes myosin head to pivot, pushing the actin filament in the opposite direction of the myosin filament. when Ca2+ is taken back up by the SR, muscle contraction is terminated. |
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Term
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Definition
| anything an animal does and how it does it. an animal directly interacts with its environment through behavior. every behavior has a cost and a reason (benefit). behavior is performed if the benefit is greater than cost. |
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Term
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Definition
| include kinesis, taxis, and instincts |
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Term
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Definition
| the animal increases/decreases level of activity as a result of environment; this corresponds to the level of comfort. example is students are more hyperactive on test day. |
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Term
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Definition
| this is the orientation response, it is guided by a stimulus- can either lead the animal to or away from certain stimulus. 4 types: phototaxis- response to light, chemotaxis- response to chemical, phonotaxis- response to sound, geotaxis- response to gravity. |
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Term
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Definition
much more complex behavior responding to a single stimulus- not learned.
Fixed action patterns are genetically determined behaviors that: are performed without learning, are stereotypic, and cannot be modified by learning. fixed action patterns are generally in response to a specific stimuli, which are called releasers. |
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Term
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Definition
animals must receive appropriate outcome after enacting a certain response to a stimulus or that response will cease.
multiple reactions to a given stimulus that do not result in the appropriate change will eventually result in the animal not responding to that stimulus |
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Term
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Definition
| the formation of the parent-offspring bond through visual learning; occurs during the critical period when animals learn certain stimuli- 5 to 25 hours after birth. baby learns what mom looks like; important for future reproduction. |
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Term
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Definition
| also known as learning; animals learn based on reward-punishment, perform more if reward and less if punished. reward/punishment has to come very quickly after behavior is performed. ultimate learning = random reward |
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Term
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Definition
ability of an animal to solve a problem without experience.
Wolfgang Kohler- chimps and bananas. the chimps learned to maneuver available resources to obtain the out of reach banana. |
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Term
| Classification of Observations |
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Definition
Occam's Razor: the simplest possible explanation is usually the best.
Morgan's Canon: never attribute a higher level of mental functioning to an animal that is inconsistent with data. |
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Term
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Definition
| all animals must learn to find food. animals can be classified as generalists or specialists based upon the food that they eat; generalists- cows, specialists- anteaters. |
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Term
| Animals must maximize food-obtaining abilities |
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Definition
| energy expended while finding/obtaining food must be less than the energy obtained from the food. |
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Term
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Definition
| concept that deals with animals maximizing energy. they ignore what they are not looking for, helping them reduce the amount of energy used in finding food. adaptations of animal's behavior reduce energy in obtaining food. |
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Term
| expenditure of energy once food is found |
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Definition
| there is usually still a cost in obtaining food after it is found; wolves seek older, sicker animals- less energy cost in obtaining. |
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Term
| Orientation/Migration in birds |
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Definition
migration in birds and homing ability in other animals involves complex systems of orientation. the first cue in navigation is sun/stars. birds can also see magnetic fields.
birds migrate from a poor environment to a warmer/better one, and sometimes back. |
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Term
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Definition
| fly around in a seemingly random pattern before choosing a path straight home. also seem to lose way and become disoriented over certain spots, characteristic of a disturbance in Earth's magnetic field. pigeons can still fly home if eyesight is disrupted or even lost. this is because their otoliths are made of iron and respond to Earth's magnetic field. |
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Term
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Definition
| involves interactions with other animals of the same species. all forms of social behavior involve communication. |
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Term
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Definition
most common in a sexual nature.
Sound: species specific
Chemical: pheromone- a chemical substance used in communication between organisms of the same species
Visual: courtship dance, butterflies, honey dance of bees- dance tells other bees direction and distance of food source; angle cut in circle indicates orientation of food in relation to the sun, intensity of abdomen wiggles tells how far to fly. |
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Term
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Definition
as density increases, so do social interactions. Individual distance- even at greatest density there is still going to be some distance between animals; "space bubble" for humans.
*Territory: always associated with a resource; it is a defined space with a resource that is defended.
*Home range: a defined region, derives from the ability to exploit a larger area of resource as a group; related to herding animals. |
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Term
| Pecking Orders (better known as social organizations) |
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Definition
| based upon dominance relationships. each individual has a position. organization is held stable by knowing your position. provides reduced conflict within the group and a great deal of stability, little aggression between members of the group. is a means of addressing efficiency to feeding. |
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Term
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Definition
Monogamy: one male, one female
Polygamy: one male, multiple females
Polyandry: multiple males, one female
Promiscuity: mating with anything that produces offspring
Factors involved: parental investment (loving offspring). determined first by gamete; how much energy goes into producing egg/sperm, what does it take to raise offspring until it can survive on its own (feeding, care, incubation, nest-building, protection)
Mating system that the animal uses is determined by equality/inequality of parental investment. relative equality = monogamy. inequality = polygamy/polyandry. when female investment is much greater than male investment, it is polygamy (ex: horses, chickens). when male investment is much greater than female investment, it is polyandry (ex: certain types of fish where male builds nest, female swims by and drops off eggs, and male cares for eggs until they hatch) |
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Term
| Costs/benefits of pheromones |
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Definition
because of the diversity of their molecular structures, pheromones can communicate very specific, information-rich messages. they are effective day and night, and they can cover a broad range of transmission distances. when used to mark territories, the pheromone can reveal a great deal about the individual (sexual status, etc).
no real costs |
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Term
| Costs/benefits of visual signals |
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Definition
these signals offer the advantage of rapid delivery of information over considerable distances; they also convey without ambiguity of the position of the signaler.
they are not very useful at night or in environments that lack light, such as caves and oceans depths. also, they can be intercepted fairly easily by other species |
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Term
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Definition
can be used at night and in dark environments. they are not hindered by objects that would interfere with visual signals, so they can be transmitted in complex environments such as forests. often better at getting the attention of the receiver because they do not have to be looking at the signaler. useful for communicating over long distances.
can place the signaler at risk for detection by predators. |
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Term
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Definition
the scientific investigation of interactions among organisms and their physical environment; along with communities and large scale nature in general.
it is NOT environmentalism. ecology is a science that generates knowledge about interactions in the natural world. as a field of inquiry, it is not inherently focused on human concerns.
its ultimate goal is to identify and understand the biotic (living) and abiotic (non-living) forces that influence the distribution and abundance of organisms. |
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Term
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Definition
*life exists only in a narrow shell extending about 3 miles deep and 5 miles high; this 8 mile shell contains all of the life in the universe as we know.
an ecosystem is defined as any ecological system with defined boundaries. it includes all of the organisms within those boundaries as well as the physical and chemical factors that influence those organisms. the global ecosystem is described above^^, which Durkohff is focusing on |
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Term
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Definition
the source of energy for the Earth. (10 to the 24th) calories of energy reach outer atmosphere from the sun each year. 30% of that is reflected, 20% is absorbed by atmosphere, and the remaining 50% reaches the surface. that 50% that reaches the surface is reflected back into the atmosphere.
Radiant energy and rotation establishes pattern of wind/rain/ocean currents; surface features (like mountains, etc) also effect these conditions. |
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Term
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Definition
energy moves through ecosystems in one direction- it cannot be recycled. nearly all energy comes from the sun, and enters the ecosystem through plants, which either use or store the energy that consumers will later eat.
nutrients (materials) cycle through ecosystems |
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Term
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Definition
| the movement of inorganic elements such as nitrogen, phosphorus, and carbon through living organisms and the physical environment. includes the water cycle, carbon cycle, phosphorus cycle, nitrogen cycle, and sulfur cycle. |
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Term
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Definition
Evaporation -> condensation -> precipatation
transpiration: water absorbed by plant, then eaten by animal. |
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Term
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Definition
CO2 in atmosphere is taken up by plants where it is altered into carbs, sugars, etc. Plants are eaten, and the animal incorporates carbon-containing compounds into its own tissues through digestion. respiration releases CO2 into the air. plants absorb the CO2 in the air, and the cycle continues.
unusual circumstance: when plants die and overwhelm decomposers, it becomes covered with sediment, and pressure and heat create peroleum (fossil fuel). |
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Term
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Definition
phosphates in soil are absorbed by plants, essentially the same as Carbon Cycle- used, incorporated, released, used...
excretion of phosphates complicated by processes of farming. |
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Term
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Definition
| nitrates are taken up by plants, plants convert to ammonia, animal eats plants, and it either excretes nitrogenous wastes or dies and decomposes to release nitrogen products back into soil. |
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Term
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Definition
energy enters via sunlight and photosynthesis. less than 1% of radiant energy that reaches the earth is transformed by photosynthesis.
materials cycle through ecosystems, energy does not. photosynthesis converts energy into carbon-containing compounds; not directly into ATP, convert into carbs and use those carbs to make everything else. everything living requires energy to stay alive. |
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Term
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Definition
Producers- photosynthesis
Consumers- ingest living things
Decomposers- break down dead things; specialized consumer |
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Term
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Definition
| description of a direct relationship between animals based on what they eat; *help us understand the flow of energy between animals*. basic pattern: sunlight -> producers -> primary consumers -> secondary consumers -> decomposers; with a few interruptors |
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Term
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Definition
| variety of plants eaten by a variety of animals, which are in turn eaten by a variety of animals. idea that everything is interrelated between living things. *help us understand relationships among organisms*. |
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Term
| energy moves in ONE direction |
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Definition
Numbers: more producers than primary consumers, more primary consumers than secondary consumers, etc. this is a result of the flow of energy.
Biomass: biological mass of organisms. same concept- "dry" weight of plant material >>> "dry weight of primary consumers.
Productivity: about 35% of energy taken in by plant simply goes to keeping the plant alive. consumers only get energy from physical compound of what they eat; cannot get energy that went into keeping that food alive. |
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Term
| 3 important principles of food chains |
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Definition
1. complete food chain begins with a producer and ends with a decomposer
2. shorter chain = most efficient (producer to decomposer is most efficient)
3. size of a population is determined by its position in the food chain. the more organisms that need to be fed, the more energy required to feed them, thus the lower they are on the food chain |
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Term
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Definition
| energy available to an organism |
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Term
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Definition
energy it can pass on to another organism.
Example: eat a pound, gain an ounce. pound is gross, ounce is net |
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Term
| Population dynamics- Introduction |
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Definition
| defined as the patterns and processes of change in populations. in ecology, major concerns are levels of populations and communities. this looks at populations to determine how communities work, how long they persist. |
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Term
| Basic periods of life histories (in population dynamics) |
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Definition
| growth; dispersal; reproduction Life Table: a means of studying the survival of a population over time. Two methods to study: vertical and horizontal. a horizontal life table follows a population throughout its life. this strategy is able to observe growth, dispersal, and reproduction patterns easily. it maps the number of individuals over a given amount of time. a vertical life table samples a population at a point in time to determine the various proportions of individuals at a given age class. Lx is number of given individuals in a certain time frame, Mx is reproductive rate at any give age class. |
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Term
| Exponential Population Growth |
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Definition
*populations always follow a specific pattern of growth, which turns exponential. factors determining growth: birth rate (b), death rate (d), initial population size. b-d=positive, population is increasing; b-d=negative, population is decreasing. so there are two components: intrinsic factors (birth and death; inherent qualities of species) and population size.
R=(b-d)N
Rate of growth=(births-deaths)Size of the population
Rate of growth is change in number of individuals divided by change in time. |
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Term
| Concept of Carrying Capacity (K) |
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Definition
| *maximum number of individuals that a population can have in a given environment; determined by resources, disease, predation, social interactions, etc. As N approaches K (carrying capacity of population), birth rates decline and death rates increase. |
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Term
| Mathematical model for carrying capacity |
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Definition
R=(b-d)N((K-N)/K)
^logistic growth equation. if N rises above K, then population will decline back to K. if N>K then (K-N)<0, so R is negative. (K-N)/K is proportion of carrying capacity that remains to be filled. |
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Term
| other factors affecting the carrying capacity |
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Definition
K is not constant: drought, predators, food, construction all affect K.
Birth rate is determined by inherent nature of organism; number of young it is capable of reproducing and number of reproductive cycles it will have.
Birth and Death rates are correlated for most species. if N remains constant, b and d cancel out. if N is decreasing, bd. |
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Term
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Definition
| can be used to evaluate population dynamics and tell population trends. it is a comparison of relative numbers of populations; reproductive and post-repro can be used to tell future growth/decline of population. pre-repro>repro>post-repro = expanding population. pre-repro=repro=post-repro = stable population. pre-repro |
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Term
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Definition
| the population exhibits decreasing growth as resources become limited; it will display an S-shaped graph. this graph will indicated that the carrying capacity has been reached and the population stops growing. |
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Term
| Density-dependent factors |
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Definition
| factors whose effect varies directly with the density of the population. as population increases, the effect of the factor increases. examples include competition within population, predation, disease. these factors are predictable, thus populations can adapt to them. population adapts by employing "life history strategies". R-SELECTED SPECIES maximize the (b-d) component of the logistic equation and PRODUCE TONS OF OFFSPRING. K-SELECTED SPECIES maximize the ability of the population to track K in the (K-N)/K component of the equation and ARE MORE STABLE; these species maintain and persist at or near the carrying capacity of their environment. |
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Term
| Density-independent factors |
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Definition
| examples include weather and changes in habitats as a result of the normal activity of other populations. usually abiotic factors, while biotic factors usually act in a density-dependent manner. |
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Term
| Human Population Patterns |
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Definition
| growth pattern is still essentially exponential. delaying average age of reproduction slows rate of population growth. K for human populations- density-dependent factors include resources and disease |
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Term
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Definition
| ways populations interact include: predator-prey interactions (involves every organism), competition (within and between populations), and symbioses (2 organisms interacting and living with each other). |
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Term
| Predator-Prey relationships |
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Definition
| every organism is a part of a food web. highly density-dependent. relationship between size of predator and prey determines how prey are taken: same size- individually, prey smaller- prey taken in groups (cows and grass), prey larger- predators attack in groups (wolves and moose). predators can eat a wide variety of organisms as prey; varied diet provides more nutritional gain. |
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Term
| Defense mechanisms in plants |
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Definition
1. thorns, thistles; very difficult to digest
2. toxic compounds
3. altered growth pattern; grass grows from base so when top is cut it can continue to grow |
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Term
| Defense mechanisms in animals |
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Definition
1. shells; make it harder to obtain food
2. cryptic coloration; camoflauge
3. speed; makes animals more costly (energy wise) to obtain
4. weapons; horns and other things used in defense make the animal more costly. |
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Term
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Definition
1. filter feeders: catches big particles
2. detrivores: eat dead animals
3. parasitoids: obtain high quality of food- kills host
4. herbivores: eat plant material
5. carnivores: eats other animals; higher quality meal requires more energy |
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Term
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Definition
predator must make many decisions: where to forage (memory, smelling winds, footprints, etc), how to find prey, which prey to choose, all of which relate to maximizing energy.
How to maximize energy: minimize time pursuing/handling prey, minimize risk of damage from prey.
Prey heirarchy: prey differ in energy return- usually related to size; prey are taken as long as they return more energy than is necessary to obtain them |
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Term
| Predation and Population size |
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Definition
| predation is the most important density-dependent factor in regulation of population size; works both ways. stage of life at which predation occurs may be an important factor in reproductive strategy; if young are eaten more often, species produces more young. predation tends to eliminate less fit: the old and ill. |
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Term
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Definition
| more cows leads to less grass which leads to less cows which leads to more grass. prey increases, predators increase shortly after, prey decreases, predators decrease, so on... |
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Term
| Mimicry as a means of avoiding predation |
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Definition
model: monarch butterfly isn't suitable prey because it eats milkweed, viceroy mimics monarch.
Batesian mimicry: edible animal mimics inedible animal. Rules for success: range of mimic and model must overlap, mimics must coevolve with the model, mimics must be rarer than model, mimics must occur later than model.
Mullerian Mimicry: evolve to look like each other because both species are equally dangerous. example: yellow and black insects. can have batesian mimics too |
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Term
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Definition
| involves direct and indirect competition. resource competition can be interspecific (between 2 or more populations) or intrAspecific (within A population). |
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Term
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Definition
| two species cannot compete for same resource indefinitely; one will become extinct or they will both evolve to partition resource. this is common is organism competition. example: certain species of warblers stick to a certain part og pine tree when territory overlaps with other warblers. |
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Term
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Definition
| Parasitism: one population benefits, the other does not; the organism must coevolve with host (food source), the key to success is not killing it, but eventually it will. |
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Term
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Definition
categorized based on end result- who benefits?
most common is predator-prey
2nd most common is competition |
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Term
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Definition
both populations benefit.
rhizobium and legumes: nitrogen-fixing bacteria
ants and acacias: acacias produce nectar not associated with flower to attract ants, ants live in hollowed out thorns and harvest nectaries and protect acacia trees and remove competitive vegatation on the forest floor
leaf miner ants and mold: ants cup up leaves, eat, regurgitate, and allow to certain mold to grow; provide mold with nutrients, eventually harvesting mold for food |
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Term
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Definition
| one population benefits while the other is unaffected; birds and trees |
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Term
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Definition
| one population is harmed and other is unaffected; very rare |
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Term
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Definition
| an organism's role in its environment. fundamental niche is potential of the organism. realized niche role is not actually played; example: partitioning of environment reduces fundamental niche |
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Term
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Definition
| groups of interacting populations |
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Term
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Definition
| groups of interacting communities |
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Term
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Definition
include guilds- organisms that have a common method of feeding/doing something. examples of guilds include "seed-eaters", carnivores, "egg-layers". the more guilds an ecosystem has, the more niches it can fill and the more robust it becomes.
species diversity or richness is number of species present. more diverse leads to more complex ecosystem; diversity: weighted measure based on abundance of species. |
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Term
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Definition
| *change in composition of an ecosystem over time. populations become established, exist for some time, then decline. it is the dynamic process of change. involves constant modification of physical environment; activities of each population alter the environment and allow new populations to become established, initial conditions are such that few populations can survive (pioneer communities). |
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Term
| two types of ecological succession |
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Definition
Primary: begins where no community has existed before; lake shore line, bare rock, volcanic island.
Secondary: reestablishes a disrupted ecosystem; return of farmland.
succession results in a climax community, which is determined by climatic conditions and physical environment. |
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Term
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Definition
1. species composition changes constantly
2. total number of species increases rapidly, then levels off
3. net primary productivity increases rapidly early, then levels off as plants die and are replaced
4. organic material in soil increases early then levels off.
5. height/complexity of plants increases
6. food webs become more complex |
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Term
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Definition
Tundra: permafrost prevents growth of large, complex plants
Boreal forest/taiga: stays above freezing for a few more months, allowing for forests to grow, but doesn't support complex systems; mostly evergreens
Deciduous forest: warmer weather, MORE PRECIPITATION
Grasslands: low precipitation, more heat; grass becomes dormant without rain; grass is climax system
Deserts: C4 plants; high temp and very little rain
Tropical Rainforest: no variation in high temp; lots of rainfall
Aquatic Habitats: marine and freshwater; organisms depend on temperature and light conditions |
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Term
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Definition
the distribution of plants and animals over the surface of the globe.
constraints on species composition of communities- factors which determine whether a species is present in a given location- include climate and species availability.
species distribution is studied in biogeography historically (never been there) and ecologically (cannot survive there) |
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Term
| Conditions for other species presence |
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Definition
| physiological capacity to survive (gills, lungs, ureotelic, etc), ecological capacity for success (nutrients, competition), physical access to location (mountains, island). |
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Term
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Definition
| *physical limitations of species distribution. continental drift, motility, historical. |
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Term
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Definition
| physical aspects (conditions) of environment. limitation by competitors. concept of constant species number- carrying capacity of an environment; equilibrium number of species existing in an ecosystem; there can be substitutions of species. |
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Term
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Definition
| islands are used as a model. it is a concept of carrying capacity equilibria. the theory is based on progression in formation of an island ecosystem. |
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Term
| factors determining species number in island biogeography |
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Definition
*species number is determined by factors affecting immigration and extinction.
size of island
diverstiy of habitats
proximity to mainland (source of immigrants) |
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Term
| predictions confirmed by observations |
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Definition
| mangrove islands off the coast of florida. cataloged everything on island, killed it and charted recolonation. within 280 days, all 4 islands returned to the exact same number of species that were there before, even if species composition differed- new species filled niches. observations proved constant number of species for an environment |
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Definition
| habitats on lands that mimic islands, such as grassland bordered by mountains or an oasis in a desert. |
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