Ecology

Question 0

decribe how the flow of matter and energy through an ecosystem

Answer 0

engery: one-eay flow
mattef: recycled

Question 1

distinguish between biotic and abiotic factors an three examples of each

Answer 1

biotic: any living parts of an enviroment ( animals, plants, bacteria)
abiotic: nonliving parts of the enviroment ( sunlight, heat, wind )

Question 2

what is the main source of energy of all life?

Answer 2

sunlight

Question 3

why are producers important to an ecosystem?

Answer 3

store energy in forms that make it available to other organisms that eat them

Question 4

what is the difference between a food chain and a food web?

Answer 4

food webs are more complex

Question 5

construct a food chain for the following: insect, leaves, hawk, & sparrow

Answer 5

leaves -> insect -> sparrow -> hawk

Question 6

about how much energy is transferred from one trophic level to the next

Answer 6

10%

Question 7

Give at least three examples of human activities that upset the balance of the stable ecosystem

Answer 7

mining and burning fossil fuels
the cleaning of land for building and farming
burning of forrests
Manufacture and use of fertilizers

Question 8

how are fossil fuels formed?

Answer 8

buried organic materials over millions of years
coil oil natural gas
strip mines big hole in the ground

Question 9

how is the carbon in fossil fuels eventually returned to the atmosphere?

Answer 9

carbon dioxide is released into the atmosphere by volcanic activity or by human activities such as the burning of fossil fuels

Question 10

what is the main cause of global warming? what gas is given off during this activity?

Answer 10

earth’s temperature is getting warmer see ice is melting sea level is rising
carbon dioxide
(green house effect -> causes earth to get warmer)

Question 11

list three factors that affect population growth?

Answer 11

birth rate
death rate
the rate at which individuals enter or leave the population

Question 12

compare exponential and logistic growth

Answer 12

e- growth pattern in which the individuals in a population reproduce at a constant rate
l- growth pattern in which a populations growth slows and then stops following a period of exponential growth

Question 13

define carrying capacity and population density

Answer 13

cc- largest number of individuals of a particular species that a particular enviroment can support
pd- number of indiviuals per unit area

Question 14

differentiate between density independent and density dependant limiting factors

Answer 14

di- affect all populations in similar ways regardless of population size and density
dd- operate strongly only when population density reaches a certain level

Question 15

give an example of a density independent limiting factor

Answer 15

hurricanes, droughts, floods

Question 16

what are three density dependent limiting factors

Answer 16

competition, predation, parasitism

Question 17

why are predator/prey relations important in an ecosystem?

Answer 17

it may cycle up and down over time

Question 18

why is an invasive species? examples

Answer 18

species that colonize new lands and negatively effect the enviroment they grow on because of limiting factors
hydrilla , ashboard, zebra muscles

Question 19

what impact do invasive species have on the ecosystems they invade?

Answer 19

they slowly take over native habitat

Question 20

what is biodiversity?

Answer 20

total of the variety of organisms in the biosphere

Question 21

why is biodiversity important?

Answer 21

lots of variations in an ecosystem

contributions to medicine and agriculture and good and services

Question 22

what are some factors that contribute to species extinction?

Answer 22

natural disasters
shortage of food
not being able to survive well

Question 23

explain the difference between ecology and evolution

Answer 23

ecology is the scientific study of interactions among organism and between organisms and their physical enviroment

Question 24

The energy released at each trophic level of the energy pyramid is usually released in this form?

Answer 24

heat

Question 25

how do producers achieve to get nutrients and energy to carry out all their life functions?

Answer 25

first producer of energy-rich compounds that are later used by other organisms

Question 26

how do consumers achieve to get nutrients and energy to carry out all their life functions?

Answer 26

organism that relies an other organisms for its energy and food supply

Question 27

how do decomposers achieve to get nutrients and energy to carry out all their life functions?

Answer 27

organism that breaks down and obtains energy from dead organic matter

Question 28

explain the different ways by which plants obtain useable nitrogen through the nitrogen cycle here on Earth

Answer 28

fertilizer , fixing bacteria , lightning