Question

1. which is true about humans and the biosphere?

a. as a result human population growth and activities, the current species extinction rate is 1,000 times more rapid than it was before the industrial revolution.
b. factors such as the availability of sufficient food and water sources that limit the growth of natural populations do not affect modern human populations.
c. human activities have increased the number of earth’s biomes and the biodiversity of populations within them.
d. the largest mass extinction event in earth’s history occurred as humans started the widespread conversion of natural ecosystems to farms and pasturelands.

1. which goal might be on humans’ environmental “to - do” list?

a. add toxic chemicals to ecosystems.
b. increase the rate of human population growth so that more people are available to consume resources.
c. introduce invasive species to new ecosystems to increase the number of species the ecosystems contain.
d. decrease the rate at which carbon dioxide and other greenhouse gases are entering the atmosphere.

1. which of earth’s layers contains a region where rock is soft and can flow very slowly because of heat inside the planet?

a. crust
b. lithosphere
c. mantle
d. outer core
e. inner core

1. in which of earth’s layers would you expect a volcanic eruption like the 1980 mount st. helens eruption to occur?

a. crust
b. uppermost mantle
c. lower mantle
d. outer core
e. inner core

1. which of earth’s layers is composed primarily of metallic elements?

a. crust
b. uppermost mantle
c. lower mantle
d. lithosphere
e. core

Explanation:

• Question 6: Human activities post - Industrial Revolution have accelerated species extinction rates. Food and water availability still limit human populations. Human activities generally reduce biodiversity and biomes, and the largest mass extinction events pre - date human - caused ecosystem conversions.
• Question 7: Reducing greenhouse gas emissions is an environmental goal. Adding toxic chemicals, increasing population growth for more resource consumption, and introducing invasive species are not positive environmental goals.
• Question 8: The mantle contains the asthenosphere, a region where rock is soft and can flow slowly due to heat.
• Question 9: Volcanic eruptions occur in the crust. Magma from the mantle rises through the crust and erupts at the surface.
• Question 10: The core of the Earth is primarily composed of metallic elements like iron and nickel.

Answer:

1. a. As a result human population growth and activities, the current species extinction rate is 1,000 times more rapid than it was before the Industrial Revolution.
2. d. Decrease the rate at which carbon dioxide and other greenhouse gases are entering the atmosphere.
3. c. mantle
4. a. crust
5. e. core