Ch. 1 Introduction: The Web Of Life

Question 1

Amphibians are ___ ___ of environmental problems.

Answer 1

Biological indicators

Question 2

Amphibian skin is permeable, meaning..

Answer 2

Pollutant molecules can pass through easily

Question 3

Amphibian eggs have no ___ ___.

Answer 3

Protective shell

Question 4

Amphibians spend part of their life on land and part in water -

Answer 4

Exposed to pollutants and UV in both environments

Question 5

Why are amphibians biological indicators of environmental problems?

Answer 5

• skin is permeable
• eggs have no protective shell
• they spend part of their life on land and part in water

Question 6

Humans have enormous ___ on the planet.

Answer 6

Impact

Question 7

Ecology -

Answer 7

Scientific study of how organisms affect - and are affected by - other organisms and their environment

Question 8

Ecology is an ___ approach.

Answer 8

Interdisciplinary

Question 9

Events in the natural world are ___.

Answer 9

Interconnected

Question 10

Even species that do not interact directly can be connected by shared ___ ___.

Answer 10

Environmental features

Question 11

Observations of pacific tree frogs suggested that ___ can cause deformities.

Answer 11

Parasites

Question 12

Deformities of pacific tree frogs occurred only in ponds which also had an aquatic ___, the intermediate host of the parasite.

Answer 12

Snail

Question 13

All frogs with deformed limbs had ___ ___.

Answer 13

Ribeiroia cysts

Question 14

Controlled experiment to test hypothesis that parasites caused deformities:

Answer 14

• tree frog eggs were exposed to parasites in the lab
• four treatments: 0, 16, 32, or 48 parasites
• as parasite load increased, survival decreased and deformities in survivors increased
• supported by other field work

Question 15

Manipulative field experiment:

Answer 15

• six ponds, three with pesticide contamination
• added tadpoles to cages
• six cages in each pond: three with mesh size allowing parasites to enter, three with mesh blocking parasites

Question 16

Exclusion cage -

Answer 16

Cage with mesh blocking anything from entering

Question 17

Manipulative field experiments on pacific tree frogs

What are the treatments?

Answer 17

Pesticides and parasites

Question 18

Pesticides alone had no effect on deformities, but..

Answer 18

Pesticides significantly weakened resistance to parasites

Question 19

___ use may also be a factor in frog deformities.

Answer 19

Fertilizer

Question 20

Fertilizer use may also be a factor:

Answer 20

• fertilizer in runoff to ponds increases algal growth
• snails that harbor parasites eat algae
• greater number of snails result in greater number of parasites

Question 21

Many human actions have also increased human ___ ___.

Answer 21

Health risks

Question 22

Damming rivers in Africa increases habitat for snails that carry ___.

Answer 22

Schistosomiasis

Question 23

What human actions have also increased human health risks?

Answer 23

• Damming rivers in Africa increases habitat for snails that carry schistosomiasis
• new diseases may be related to human activities
• humans expanding into more wilderness areas, contacting more animal hosts increases exposure to “novel” viruses

Question 24

Birds are primary host and mosquitoes are vectors for what virus that spread from New York City?

Answer 24

West Nile

Question 25

West Nile Mammals are ___ carriers.

Answer 25

Dead end

Question 26

___ is a branch of biology that combines information about organisms and the physical world.

Answer 26

Ecology

Question 27

Environmental science is even more interdisciplinary Incorporates concepts from..

Answer 27

- the natural sciences - the social sciences - focuses on solutions to environmental problems

Question 28

Early ecological views:

Answer 28

- a "balance of nature" | - each species has a distinct role to play in maintaining that balance

Question 29

A "balance of nature" -

Answer 29

Natural systems are stable and tend to return to an original state after disturbance

Question 30

Tipping points -

Answer 30

Natural systems do not necessarily return to their original state after a disturbance

Question 31

One view that has stood the gets of time:

Answer 31

- events in nature are interconnected | - a change in one part of an ecological system can alter other parts of that system

Question 32

Some ecological maxims:

Answer 32

- you can never just do one thing - everything goes somewhere - no population can increase in size forever - there is no free lunch - evolution matters - time matters - space matters - life would be impossible without species interactions

Question 33

Ecologists must select appropriate ___ of study.

Answer 33

Scales

Question 34

Small spatial scales:

Answer 34

Soil microorganisms

Question 35

Large spatial scales:

Answer 35

Atmospheric pollutants

Question 36

Short temporal scales:

Answer 36

Leaf response to sunlight

Question 37

Long temporal scales:

Answer 37

How species change over geologic time

Question 38

Ecologists study interactions in nature across many levels of ___.

Answer 38

Organization

Question 39

Ecological studies usually emphasize ___, ___, ___, or ___.

Answer 39

Individuals, populations, communities, or ecosystems

Question 40

A population -

Answer 40

Group of individuals of a single species that live in a particular area and interact with one another

Question 41

A community -

Answer 41

Association of populations of different species living in the same area

Question 42

Organism - Population - Community - Biosphere -

Answer 42

- fish - school of fish - coral reef - all of that together

Question 43

An ___ is a community of organisms plus the physical environment in which they live.

Answer 43

Ecosystem

Question 44

___ are areas with substantial differences, typically including multiple ecosystems.

Answer 44

Landscapes

Question 45

The biosphere:

Answer 45

- all the worlds ecosystems taken together | - all living organisms on Watch plus environments in which they live

Question 46

Adaptation -

Answer 46

A feature of an organism that improves its ability to survive or reproduce in its environment

Question 47

Natural selection -

Answer 47

An evolutionary process in which individuals that possess particular characteristics survive or reproduce at a higher rate than other individuals because of those characteristics

Question 48

Producer -

Answer 48

An organism that uses energy from an external source, such as the sun, to produce its own food without having to eat other organisms or their remains

Question 49

Consumer -

Answer 49

An organism that obtains its energy by eating other organisms or their remains

Question 50

Net primary production (NPP) -

Answer 50

The amount of energy (per unit of time) that producers fix by photosynthesis or other means, minus the amount they use in cellular respiration

Question 51

Nutrient cycle -

Answer 51

The cyclic movement of a nutrient between organisms and the physical environment

Question 52

All living things evolve ->

Answer 52

Change over time

Question 53

Three variables important for natural selection to operate:

Answer 53

- variation among individuals within the population - heritability of the variations - differential fitness due to variation

Question 54

Energy enters community when ___ capture energy from an external source and uses that energy to produce food.

Answer 54

Producers

Question 55

___ moves through ecosystems in a single direction only.

Answer 55

Energy

Question 56

___ are continuously recycled from the physical environment to organisms and back again.

Answer 56

Nutrients

Question 57

Ecologists use several methods to answer questions about the natural world:

Answer 57

- observational studies in the field - controlled experiments in the laboratory - manipulative experiments in the field - quantitative models

Question 58

The study of global climate change involves using a mixture of..

Answer 58

- observational studies - small-scale experiments - quantitative models

Question 59

Climate change -

Answer 59

A directional change in climate that occurs over 30 years or longer

Question 60

Key aspects of good experimental design:

Answer 60

- replication | - randomization

Question 61

Replication -

Answer 61

Perform each treatment more than once As number of replicates increases, it becomes less likely that the results were actually due to a variable that was not measured or controlled

Question 62

Increased ___ ___ within treatments decreases likelihood that effects are due to chance alone.

Answer 62

Sample size

Question 63

Randomization -

Answer 63

- assign treatments at random | - helps limit effects of unmeasured variables

Question 64

Standard ___ ___ are used to determine significant effects.

Answer 64

Statistical analyses

Question 65

Scientists learn about the natural world by a series of steps called the ___ ___.

Answer 65

Scientific method

Question 66

Inductive reasoning -

Answer 66

Make observations and ask questions

Question 67

Deductive reasoning -

Answer 67

Use previous knowledge or intuition to develop a testable hypothesis

Question 68

Scientific method:

Answer 68

- make observations and ask questions - use previous knowledge or intuition to develop a testable hypothesis - make a testable prediction based on hypothesis - evaluate hypothesis by examining results of experiments, a comparative observational study, or quantitative models - use results to modify the hypothesis, to pose new questions, or to draw conclusions about the natural world

Question 69

Alternative hypothesis -

Answer 69

Different "explanations" for phenomenon

Question 70

Scientific theory -

Answer 70

- from consistent results | - supported by lots of data, usually from many different sources