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297 Cards in this Set
- Front
- Back
stimulus
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a signal that causes an organism to react in some way
|
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response
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an action or change in behavior that occurs in reaction to a stimulus
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imprinting
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a learned behavior
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territory
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an area that is occupied and defended by an animal or groups of animals
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migration
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the regular periodic journey of an animal from one place to another and back again for feeding and/or reproducing
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hibernation
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a state of greatly reduced body activity that occurs during winter
|
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How do animals benefit from living in groups?
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it enables them to cooperate to get food, to raise their young and to protect themselves against predators
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How does the nervous system help the body maintain homeostasis?
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directing the body to respond appropriately to the information it receives
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neuron
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a cell that carries information through the nervous system
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axon
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a threadlike extension of a neuron that carries nerve impulses
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dendrite
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a threadlike extension of a neuron that carries nerve impulses toward the body
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sensory neuron
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a neuron that picks up stimuli from the internal or external environment and converts each stimulus into a nerve impulse
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motor neuron
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a neuron that sends an impulse to a muscle or gland, causing a muscle or gland to react
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central nervous system
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the division of the nervous system consisting of the brain and spinal cord
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brain
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the part of the central nervous system that is located in the skull and controls most functions in the body
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spinal cord
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the thick column of nerve tissue that links the brain to most of the nerves in the peripheral system
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cerebrum
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the part of the brain that interprets impulses from the senses, controls movement, and carries out complex mental processes such as learning and remembering
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cerebellum
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the part of the brain that coordinates muscle action and helps maintain homeostasis
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brain stem
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the part of the brain that lies between the cerebellum and spinal cord and controls the body's involuntary action
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concussion
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a bruiselike injury of the brain that occurs when the soft tissue of the brain collides against the skull
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voluntary
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type of action controlled by the somatic nervous system
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involuntary
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type of actions controlled by the autonomic nervous system
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reflex
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an automatic response that occurs very rapidly and without conscious control
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paralysis
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often resulting from a spinal cord injury, this is the loss of movement in some part of the body
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pupil
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light enters the eye through this opening
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lens not focusing properly
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cause of nearsightedness and farsightedness
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vibrations
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how sound is produced
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balance
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structures in the inner ear control this
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Why is pain an important sensation?
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alerts the body to possible danger
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hormones
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chemical product of an endocrine gland
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What causes nearsightedness and farsightedness?
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Lens not focusing properly
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How is sound produced?
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vibrations
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Structures in our inner ear control our sense of
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balance
|
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Why is pain an important sensation
|
alerts the body to possible danger
|
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What are hormones?
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the chemical product of an endocrine gland
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What is the function of hormones?
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turn on/off, speed up/down the activities of different organs
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Which endocrine gland controls many body activities such as growth from infancy to adulthood?
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pituitary gland
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Why do hormones cause changes on in specific body organs?
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its chemical structure only allows it to interact with target cells
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What is the joining of a sperm and an egg called?
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fertilization
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What is produced when fertilization occurs?
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a fertilized egg or zygote
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Where are human eggs usually fertilized?
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Fallopian tubes
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Eggs are produced in the
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ovaries
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Sperm are produced in the
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testes
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Sex cells contain how many chromosomes?
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23
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In a female's body, an egg develops in an ovary and the uterus prepares for the arrival of a fertilized egg during what cycle?
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Menstrual
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The menstrual cycle is controlled by hormones of this system.
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endocrine system
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producer
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an organism that can make its own food
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consumer
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an organism that obtains energy by feeding on other organisms
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herbivore
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a consumer that only eats plants
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carnivore
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a consumer that only eats meat
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omnivore
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a consumer that eats both meat and plants
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scavenger
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a carnivore that feeds on bodies of dead organisms
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decomposer
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an organism that breaks down wastes and dead organisms and returns the raw materials to the ecosystem
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food chain
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a series of event in which one organism eats another and obtains energy
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food web
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consists of overlapping food chains in an ecosystem
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energy pyramid
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shows the amount of energy that moves from one feeding level to another in a food web
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evaporation
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the process by which molecules of liquid absorb energy
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condensation
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the process by which gas changes to a liquid
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precipitation
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rain, snow, sleet or hail
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nodules
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bumps on the rock where bacteria live
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biogeography
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the study of where organisms live
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continental drift
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as plates move the continents move with them
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climate
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the typical weather pattern in an area over a long period of time
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biome
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a group of land ecosystems with similar climates and organisms
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producers
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the level of an energy pyramid that has the most available energy
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free producer
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first organism in a food chain
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tundra
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an extremely cold and dry biome
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desert
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biome that receives less than 25 centimeters of rain each year
|
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Why do a large variety of plants grow in a tropical rain forest?
|
Large rain amount
|
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Four types of freshwater ecosystems
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streams
rivers lakes pond |
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habitat
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the specific environment that provides the things an organism needs to live, grow and reproduce
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biotic factor
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a living part of an organism's habitat
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abiotic factor
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a non-living part of an organism's habitat
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population
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all the members of one species in a particular area
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species
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a group of organisms that are physically similar that can mate and produce offspring that can also mate and produce offspring
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sampling
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to estimate by counting the number of organisms in a small area then multiply to get the larger area
|
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estimate
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an approximation of a number based on a reasonable assumption
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direct observation
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to count all the members in a population
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indirect observation
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to count their nests and average the number of organisms living in a nest
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community
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all the different populations that live together in an area
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ecosystem
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the community of organisms that live in an area along with their non-living surroundings
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ecology
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the study of how an organism interacts with their environment and each other
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ecologist
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a person who studies ecology
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carrying capacity
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the largest population that an area can handle
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niche
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the role of an organism in its habitat or how it makes its living
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population density
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the number of individuals in an area of a specific size
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immigration
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moving into a population
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emigration
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leaving a population
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limiting factor
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an environmental factor that prevents a population from increasing
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adaptations
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a behavior or physical characteristic that allows an organism to survive or reproduce in its environment
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competition
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the struggle between organisms to survive as they attempt to use the same limited resource
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predation
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an interaction in which one organism kills another for food
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prey
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an organism that is killed and eaten by another organism
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predator
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the organism that does the killing in a predation interaction
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symbiosis
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a close relationship between two organisms of different species that benefits at least one of the organisms
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mutualism
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a close relationship between two organisms of different species in which both organisms benefit
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commensalism
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a relationship between two species in which one species benefits and the other is neither helped nor harmed
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parasitism
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a relationship in which one organism lives on or in a host and harms it
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host
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the organism that a parasite or virus lives in or on
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primary succession
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the series of changes that occur in an area where no soil or organisms exists
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pioneer species
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the first species to populate an area
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secondary succession
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the series of changes that occur in an area where the ecosystem has been disturbed but where the soil and organisms still exist
|
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What equation is used to calculate population density?
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number of individuals/
unit area |
|
an ecologist counts 75 cardinals in an area measuring 15 square kilometers. What is the population density of the cardinals?
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75/15 = 5 per square kilometer
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List the levels of ecological organization from the smallest to the largest
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organism, population, community, ecosystem
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What are four limiting factors for population?
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food
water weather space |
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What abiotic factors are needed for plants to make their own food in photosynthesis?
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water, sunlight, oxygen, temperature, soil
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All the abiotic and biotic factors in an area together make up a(n)
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ecosystem
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Explain how the red-tailed hawks' interaction with the saguaro cactus is an example of commensalism.
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The saguaro cactus gives the red-tailed hawk shelter and it keeps the hawks away from danger. The cactus is not helped or harmed by the hawk.
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List the 6 nutrients that are necessary for human health
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vitamins, minerals, proteins, fat, carbohydrates, water
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What nutrient is needed for all body processes to take place?
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water
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Which nutrient is made up of amino acids?
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proteins
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What is a calorie?
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The amount of energy needed to raise the temperature of one gram
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What substance in the mouth contains an enzyme that begins the process of chemical digestion?
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saliva
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The energy our body needs comes from where?
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food
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What substance lines the esophagus, making food easier to swallow?
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mucus
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What is another name for the cardiovascular system?
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circulatory system
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List the three functions of the circulatory system
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delivering needed materials
removing waste products fighting disease |
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How are needed substances (oxygen and glucose) carried to the body cells?
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through the blood/circulatory system
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What is the function of the atria?
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to receive blood
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Explain the function of a pacemaker?
|
this sends out signals that make the heart muscle contract
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Blood vessels that carry blood away from the heart are called
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arteries
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Blood vessels that carry blood back to the heart are called
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veins
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In which blood vessels are materials exchanged between the blood and the body cells?
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capillaries
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What causes blood pressure?
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blood exerts force
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List the four components of blood and their functions
|
plasma - liquid part of blood
red blood cells - take oxygen through the blood white blood cells - fight disease platelets - form blood clots |
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What determines blood types?
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markers
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what is the function of lymph nodes?
|
trap bacteria
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Define atherosclerosis
|
a condition in which the artery walls thickens from a buildup of cholesterol
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What can happen when atherosclerosis develops in the coronary arteries?
|
heart attack
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Why is exercise important for cardiovascular health
|
this strengthens the heart muscle
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Why are valves in the heart important?
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these keep blood from flowing backwards
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What does it mean if your pulse rate increases?
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You are working harder when this happens
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What instrument is used to measure blood pressure?
|
sphygmomanometer
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Define hypertension
|
a disorder in which a person's blood pressure is consistently high
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What makes up what percent of plasma?
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90%
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How many loops does the circulatory system contain
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2
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What part of the respiratory system divide into smaller tubes that resemble the branches of a tree?
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broncus
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What are the hairlike structures lining the nasal cavities and trachea called?
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cila
|
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Each alveolus is surrounded by a network of what?
|
capillaries
|
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Which chemical in tobacco smoke is an addictive drug?
|
nicotine
|
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tobacco smoke contains what harmful gas that replaces some of the oxygen that red blood cells normally carry?
|
carbon monoxide
|
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Describe how bronchitis affects the respiratory system
|
an irritation of the breathing passages in which small passages become narrower than normal
|
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Describe how emphysema affects the respiratory system
|
a disease that destroys lung tissue
|
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Describe how lung cancer affects the respiratory system
|
Cancerous growths, or tumors, take away space in the lungs that are used for gas exchange.
|
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What substances are found in urine (in normal conditions)?
|
urea and water
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Where is urea produced?
|
liver
|
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What function do the kidneys perform?
|
filter blood; control amount of water
|
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To what storage place do the ureters carry the urine?
|
uretha and bladder
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Urea, excess water, and other waste materials are eliminated in a watery fluid called
|
urine
|
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What is homeostasis?
|
the maintenance of stable internal conditons
|
|
No matter what the temperature is around you, your internal body temperature will be close to
|
37 degrees Celcius
|
|
What fills the spaces in bones?
|
marrow
|
|
List the functions of the skeleton
|
provides shape and support
enables you to move protects your organs produces blood cells stores minerals and other materials until your body needs them |
|
Much of a newborn baby's skeleton is made of what
|
cartilage
|
|
Muscle tissue is found where and does what
|
leg
contracts or shortens to make your body move |
|
Nervous tissue is found where and does what
|
brain
directs and controls the brain and other body parts |
|
Connective tissue is found where and does what
|
bone
provides support for your body and connects all its parts |
|
epithelial tissue is found where and does what
|
skin
protects the delicate structures that lie beneath it |
|
How does exercise help maintain healthy bones?
|
Exercise helps bones grow in size and keeps them from breaking.
|
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Why are dairy products important in maintaining healthy bones?
|
Dairy products provide calcium
|
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List the level of organization in the body's systems starting with the smallest
|
cells
tissues organs organ systems |
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What structure directs the cell's activity?
|
Nucleus
|
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What are the bones that form the backbone are called?
|
The vertebrae
|
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Where is compact bone located?
|
Beneath the bone's outer membrane
|
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What are ligaments?
|
Strong connective tissue that holds bones together
|
|
Describe a hinge joint and tell where it is located in the body
|
a type of joint that allows forward and backward movement. Ex. knee/elbow
|
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Describe a ball and socket joint and tell where it is located in the body
|
a type of joint that allows free movement. Ex: arms, hips, shoulders.
|
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Describe a pivot joint and tell where it is located in the body
|
a type of that that allows one bone to move around another. ex: neck and kneecap
|
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Describe a gliding joint and tell where it was located in the body
|
a type of joint that allows the bones to slide around one another. ex: wrist and ankle
|
|
Where are immovable joints located in the body?
|
skull
|
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What minerals do bones contain?
|
calcium and phophorus
|
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Describe cardiac muscle and give example of where it is located.
|
muscle cells are striated and are voluntary. They are found in the heart
|
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Describe smooth muscle tissue and give example of where it is located.
|
muscle that has two parallel lines and something that looks like an eye between the lines. Found in stomach and blood vessels
|
|
Describe skeletal muscles and give example of where it is located
|
muscle that has two parallel lines and something that looks like an eye on the lines. Ex: bones
|
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Which types of muscle tires quickly during exercise
|
smooth muscle
|
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Which type of muscle is found only in the heart?
|
cardiac muscle
|
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Why do skeletal muscles work in pairs?
|
They can only contract
|
|
What type of involuntary muscle moves food through the digestive track?
|
smooth muscle
|
|
How do the pairs of skeletal muscles move together?
|
One contracts while the other relaxes
|
|
Why is exercise important for muscles?
|
It helps them grow in size
|
|
What is the best way to prevent osteoporosis?
|
Weight-bearing exercise, calcium in diet
|
|
How does the skin protect the body from disease?
|
It forms barriers around the body
|
|
Where are nerve and blood vessels in the skin located?
|
Dermis
|
|
Where are the living cells in the epidermis located?
|
beneath the dead cells
|
|
How does skin help regulate body temperature?
|
sweating
|
|
What is melanin?
|
Pigment in the skin that gives skin its color
|
|
Are bones alive?
|
Yes. They are made up of living cells.
|
|
List three functions of the digestive system
|
breaks food into molecules that the body can use.
molecules are absorbed into the blood and carried through the body. wastes are eliminated from the body |
|
How long is the digestive system from beginning to end?
|
9 meters
|
|
Define digestion
|
The process by which your body breaks down food into small nutrient molecules
|
|
Name two kinds of digestion
|
1. mechanical
2. chemical |
|
Explain mechanical digestion
|
occurs when you bite into a sandwich and chew it into smaller pieces
|
|
Explain chemical digestion
|
chemicals are produced by the body which break food into smaller chemical blocks
|
|
Define absorption
|
the process by which nutrients molecules pass through the wall of your digestive system into the blood stream
|
|
Where do both mechanical and chemical digestion begin
|
mouth
|
|
What are enzymes?
|
Proteins that speed up chemical reactions in the body
|
|
How are prevented from entering the windpipe
|
the epiglottis seals off the windpipe for this purpose
|
|
Identify esophagus
|
muscular tube that connects the mouth to the stomach
|
|
mucus
|
a thick slippery substance produced by the body
|
|
peristalsis
|
involuntary waves of the muscle contraction
|
|
stomach
|
a j-shaped muscular pouch located in the abdomen
|
|
Where does most mechanical digestion occur?
|
stomach
|
|
What enzyme is found in digestive juice?
|
pepsin
|
|
Explain the role of pepsin during chemical digestion
|
breaks food down into short chains of amino acids
|
|
why doesn't stomach acid burn a hole in your stomach
|
cells in the stomach lining produce a thick coating of mucus
|
|
when the thick liquid leaves the stomach, where does it go?
|
the small intestine
|
|
Describe the small intestine
|
the small intestine is 2-3 cm wide and 6 m long
|
|
what is the largest organ inside the body
|
liver
|
|
What is the role of the liver in the digestive system?
|
produce bile
|
|
Bile
|
a substance that breaks up fat particles
|
|
Gallbladder
|
organ that stores bile
|
|
pancreas
|
triangular organ that lies between the stomach and the small intestine; it breaks down fats, starches, and proteins
|
|
villi
|
millions of tiny finger-shaped structures
|
|
How do nutrients from the small intestine get to the rest of the body
|
Villi passes into blood vessels
|
|
describe the large intestine
|
1.5 meters long; last section of the digestive system, it runs up the left side of the abdomen
|
|
explain how bacteria found in the large intestine can be helpful
|
they make certain vitamins
|
|
what happens to water as the remaining material moves through the intestines
|
it is absorbed into the blood stream
|
|
rectum
|
the short tube that ends the large intestine
|
|
where is waste material eliminated from the body
|
anus
|
|
where do your body cells get oxygen
|
the air you breath in is taken to the body's cells through the blood stream
|
|
What are two functions of the respiratory system
|
taking in oxygen
removing carbon dioxide & water |
|
why do cells need oxygen?
|
for the energy-releasing chemical reactions
|
|
respiration
|
the process in which oxygen and glucose undergo a complex series of chemical reactions inside a cell
|
|
explain the difference between respiration and breathing
|
breathing is the movement of air into and out of the lungs; respiration is the chemical reaction inside the body
|
|
respiration produces what two substances
|
carbon dioxide and water
|
|
where your respiration system eliminate carbon dioxide and some water
|
through the lungs
|
|
During respiration, oxygen reacts with glucose to release what?
|
energy
|
|
Explain how the respiratory, digestive, and circulatory systems work together during respiration.
|
the respiratory system brings oxygen into your lungs. the digestive system absorbs glucose from the food you eat; the circulatory system carries both oxygen and the glucose to your cells
|
|
as air travels from the outside environment to the lungs, it passes through what structures?
|
nose,
pharynx, trachea bronchi lung |
|
Explain what happens as air moves through the nose
|
air moves through the nose into the nasal cavities. some of the cells have living mucus which traps dust
|
|
What causes sneezing?
|
particles and bacterial in the lining of your throat and nose
|
|
another name for the throat is the
|
pharynx
|
|
the pharynx is part of which two systems
|
respiratory and digestive
|
|
another word for the windpipe is the
|
trachea
|
|
What lines the trachea?
|
cilia and mucus
|
|
Explain the roll of the cilia and mucus in the trachea
|
the cilia sweep upward moving mucus toward the pharynx; the mucus cleans
|
|
What causes you to cough?
|
when particles irritate the lining of the trachea
|
|
what causes a person to choke
|
if food enters the trachea
|
|
how is food prevented from entering the trachea?
|
the epiglottis folds over the trachea
|
|
what are the bronchi?
|
the passages that direct air to the lungs
|
|
What causes sneezing?
|
particles and bacterial in the lining of your throat and nose
|
|
another name for the throat is the
|
pharynx
|
|
the pharynx is part of which two systems
|
respiratory and digestive
|
|
another word for the windpipe is the
|
trachea
|
|
What lines the trachea?
|
cilia and mucus
|
|
Explain the roll of the cilia and mucus in the trachea
|
the cilia sweep upward moving mucus toward the pharynx; the mucus cleans
|
|
What causes you to cough?
|
when particles irritate the lining of the trachea
|
|
what causes a person to choke
|
if food enters the trachea
|
|
how is food prevented from entering the trachea?
|
the epiglottis folds over the trachea
|
|
what are the bronchi?
|
the passages that direct air to the lungs
|
|
what causes sneezing?
|
when particles and bacteria irritate the lining of your throat and nose
|
|
another name of the pharynx
|
throat
|
|
the pharynx is part of which two systems
|
respiratory and digestive
|
|
another word for windpipe is
|
trachea
|
|
what lines the trachea
|
cilia and mucus
|
|
explain the role of the cilia and mucus in the trachea
|
the cilia sweep upward moving mucus towards the pharynx. the mucus cleans the trachea when it's expelled/swallowed
|
|
what causes you to cough?
|
when particles irritate the lining of the trachea
|
|
what causes a person to choke?
|
when food enters the trachea
|
|
how is food prevented from entering the trachea?
|
the epiglottis folds over the trachea
|
|
What are the bronchi?
|
the passages that direct air to the lungs
|
|
The main organs of the respiratory system are the
|
lungs
|
|
describe the alveoli
|
tiny sacs of lung tissue specialized for the movement of gases between air and blood
|
|
Where are the alveoli located
|
each alveoli is surrounded by capillaries
|
|
Explain the entire process of gas exchange that takes place in the alveoli
|
the blood is carrying a lot of carbon dioxide and little oxygen. When it moves through the capillaries, oxygen attaches to the hemoglobin in the red blood cell. At the same time the blood is getting rid of carbon dioxide
|
|
An adult's lungs contain about how many alveoli?
|
300 million
|
|
Why are your lungs able to absorb a large amount of oxygen?
|
the oxygen is absorbed in the lungs through the 300 million+ alveoli
|
|
why do we have a large supply of oxygen when we are involved in strenuous activities?
|
because of the surface area of the alveoli
|
|
the rate at which you breathe depends on what?
|
the body's need for oxygen
|
|
what controls breathing
|
muscles
|
|
what is the diaphragm?
|
a large, dome-shaped muscle at the base of the lungs
|
|
explain the process of breathing
|
when you inhale, the rib cage contracts. at the same time, the diaphragm contracts and moves downward. the combined actions make the chest cavity larger. the same amount of air now occupies a larger space causing the air in your lungs to increase. When the exhale the rib muscles and diaphragm relax causing the air to be expelled.
|
|
another name for the voice box is
|
larynx
|
|
where is the larynx located
|
top part of the trachea
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what are vocal cords
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folds of connective tissue
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how is the sound of your voice produced?
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muscles make the vocal chords contract
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the process of removing wastes from the body is called
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excretion
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what is the role of the excretory system in the body?
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it collects wastes produced by cells and removes the wastes from the body
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what are examples of wastes that need to be removed
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excess water and urea
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what four parts of the excretory system function to eliminate urea and excess water from the body?
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kidneys, ureters, urinary bladder, urethra
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What are the major organs of the excretory system
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kidneys, bladder
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Explain how the kidneys act like filters
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they remove waste but keep materials that the body needs
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What is urine?
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a watery fluid that contains urea and other wastes.
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urine flows from the kidneys through two narrow tubes called
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ureters
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describe the urinary bladder
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a sac-like muscular organ that stores urine
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what is the job of the urinary bladder
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to store urine
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where does urine leave the body
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through the urethra
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what important structures are found in the kidneys?
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nephrons
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What is the function of the nephrons?
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to remove wastes from the blood; produce urine
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How do kidneys filter wastes?
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1. blood flows from an artery into a nephron in the kidney
2. the materials that were removed from the blood passes into a long twisting tube. The tube is surrounded by capillaries. 3. As the filtered materials flows through the tube most of the water and glucose are reabsorbed into the blood. Most of the urea stays in the tube. 4. blood reaches a cluster of capillaries. There, urea, water, glucose and other materials are filtered through the blood. These materials pass into the capsule that surrounds the capillaries. 5. after the reabsorption process is complete, the liquid that remains in the tube is released to the bladder |
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If glucose is found in the urine, what might this indicate?
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the person might be diabetic
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If protein is found in the urine, what does this mean?
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that the kidneys are not functioning properly
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How does excretion help the body maintain homeostasis
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it keeps the internal environment stable and free of harmful chemicals
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explain how each organ of excretion helps maintain homeostasis - kidneys
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regulating the amount of water in your body
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explain how each organ of excretion helps maintain homeostasis - lungs
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when you exhale carbon dioxide and small water gets removed from the body
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explain how each organ of excretion helps maintain homeostasis - skin
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water and urea are execreted from the body
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explain how each organ of excretion helps maintain homeostasis - liver
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produces urea
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