Chapter 43: Global Ecology and Conservation Biology

Question 1

What do human activities threaten Earth’s?

Answer 1

biodiversity

Question 2

What is the human population no longer doing?

Answer 2

growing exponentially, but it is still increasing rapidly

Question 3

What are the four major threats to biodiversity?

Answer 3

habitat loss, introduced species, over harvesting, global change

Question 4

What are small populations vulnerable to?

Answer 4

inbreeding and genetic drift

Question 5

What does MVP stand for

Answer 5

Minimum viable population

Question 6

What is minimum viable population?

Answer 6

the minimal population size at which a species is able to sustain its number

Question 7

What has human activities nearly doubled Earth’s supply of?

Answer 7

fixed nitrogen abailable to primary producers

Question 8

What way has human activites doubled Earth’s supply of fixed nitrogen?

Answer 8

industrial fertilizers

Question 9

WHat is usable nitrogen?

Answer 9

nitrates

Question 10

What is a dead zone?

Answer 10

the result of phytoplankton bloom (due to nutrient influx) –> phytoplankton die-off –> resultant decomposition of phytoplankton depletes oxygen levels

Question 11

What is eutrophication of lakes?

Answer 11

the result of algae and cyanobacteria bloom and die-off; similar to dead zone

Question 12

What is biomagnification?

Answer 12

humans release an immense variety of toxic chemical into the biosphere with little regard or understanding of their consequence. These chemicals become more concentrated in successive trophic levels (mainly in adipose/fat) of a food web

Question 13

What is DDT?

Answer 13

a widely used incesticide, this has led to a decrease in pelicans, ospreys, and eagles

Question 14

Why has the concentration of CO2 in the atmosphere been increasing?

Answer 14

the burning of fossil fuels and deforestation

Question 15

Over what years have CO2 levels increased fromm 274 ppm to 400 ppm?

Answer 15

150 years

Question 16

What are the greenhouse effect on organisms?

Answer 16

plant migration, shifting geographic range of terrestrial, marine and freshwater organisms, loss of arctic ice habitats for polar bears, seals, etc. temperature changes affects enzymatic reactions, changes in animal behavior

Question 17

What does the ozone layer protect the Earth from?

Answer 17

harmful UV rays

Question 18

What will our population be in 2050?

Answer 18

9 billion

Question 19

What is Earth’s carrying capacity?

Answer 19

10-15 billion