Quiz 2: Biodiversity, Evolution & Ecology

Question 1

what is an example of a significant economic benefit from protecting biodiversity in rain forests and coral reefs?

Answer 1

production of chemicals to manufacture medicines

Question 2

what are the two processes that determine the world’s current biodiversity

Answer 2

extinction and speciation

Question 3

what is the most likely location of a biodiversity hotspot

Answer 3

islands

Question 4

what term best describes the loss of a particular population from a given area (but not the entire species globally)

Answer 4

extirpation

Question 5

European rabbits were introduced into Australia and quickly spread, reproduced, and became a terrible pest. They eat up to $600 million worth of food and pasture crops annually, and have damaged the populations of many native plants and the populations of animals that eat the plants. Twice in the past 50 years, rabbit diseases have been introduced to try to control the population, with some success. This is a case where an invasive species did what to the genetic diversity of the native species

Answer 5

reduced the genetic diversity of the native species

Question 6

what is biodiversity

Answer 6

variety of all living things on Earth

Question 7

What is something that is not true of endemic species

Answer 7

they are less susceptible to extinction than other species

Question 8

what is the carrying capacity of a population

Answer 8

the population size that a habitat can support indefinitely with available resources

Question 9

define minimum viable population

Answer 9

smallest number of individuals that allows the population to survive long term

Question 10

what does the logistic growth model describe

Answer 10

population that grows rapidly at small numbers, but whose growth rate slows and eventually stops as it reaches the number that the environment can support

Question 11

what is an example of a density dependent factor

Answer 11

ice storm causing damage to trees and shrubs

Question 12

a single bacterium is put in an environment with no competition. as long as resources remain unlimited, how will the bacterial population respond

Answer 12

it will reproduce exponentially

Question 13

when are populations expected to grow close to or at their intrinsic (or maximum) rate of growth

Answer 13

when their numbers are low

Question 14

what is an example of a characteristic that is not required when describing a particular biome

Answer 14

size

Question 15

what terrestrial biome has the highest diversity of species

Answer 15

tropical rainforest

Question 16

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

Answer 16

a food web shows interactions among all the species of a community instead of just a single line of energy transfer between single trophic levels

Question 17

cattle egrets follow cattle around b/c cattle disturb insects as they walk, making the insects easier for the egrets catch. there is no cost or benefit to the cattle from this interaction. what type of interaction is involved?

Answer 17

commensalism

Question 18

what does the concept of the trophic pyramid explain

Answer 18

each transfer of energy as you move up the food web results in a loss of about 90%

Question 19

why is it important to learn how ecosystems function

Answer 19

-help humans and other species continue living and thriving on earth
-protect current ecosystems
-help restore already damaged ecosystems
-help scientists learn about complexities of biomes

Question 20

what appears to be the cause of eutrophication that has taken place in the Gulf of St. Lawrence and other coastal locations around the world

Answer 20

excess nutrients from fertilizers

Question 21

energy usually leaves an ecosystem in which form

Answer 21

heat

Question 22

why is nitrogen often in short supply in terrestrial ecosystems

Answer 22

atmospheric nitrogen cannot be used by most organisms - needs to be converted to useful forms by bacteria and cyanobacteria

Question 23

why are biogeochemical cycles crucial to ecosystem function

Answer 23

all chemical elements including nutrients are in limited supply and must be recycled

Question 24

grain is eaten by cows and cows are eaten by humans. if the energy transfer between each trophic level is 10%, how much grain is required to produce 70kg of human biomass

Answer 24

7000kg

Question 25

Biologists studying a population of birds observe that individual birds with average-sized wings survive severe storms better than those individual birds with either longer wings or shorter wings. Over time, the population is made up of more birds with average-sized wings. What term would apply to this situation?

Answer 25

stabilizing selection

Question 26

what is an example of a human activity that has the potential to influence selection and affect evolution

Answer 26

use of pesticides, antibiotics, herbicides

Question 27

Species are considered ______ when they face a high risk of extinction in the immediate future. Species are considered ________ when they are in danger of becoming _______ in the near future.

Answer 27

endangered; threatened; endangered

Question 28

What term describes the intentional breeding for certain traits or combination of traits, commonly used in agriculture?

Answer 28

artificial selection

Question 29

what is extinction

Answer 29

describes the disappearance of a species from Earth

Question 30

in Earth’s history, there has/have been _______ major extinction event(s) leading to the loss of 50% or more of the species present

Answer 30

five