Test 3 (chap 16-20)

Question 1

A population is:

Answer 1

a group of individuals of the same species that live in the same general location and have the potential to interbreed.

Question 2

Which statement regarding populations is true?

Answer 2

Birth rates, death rates, as well as immigration and emigration rates are all features of a population.

Question 3

When a population grows in proportion to its current size (e.g., bigger populations grow faster), that population is experiencing ________ growth.

Answer 3

exponential

Question 4

During logistic growth, the per capita rate of increase:

Answer 4

approaches zero after the population reaches one-half of its carrying capacity.

Question 5

The lynx-snowshoe hare population dynamic pictured here represents an example of population:

Answer 5

oscillation

Question 6

The graph shows the population size at which a population can most effectively be utilized for natural resources. What appears to happen when the population reaches its carrying capacity?

Answer 6

The population stays the same size.

Question 7

Which characteristic is associated with a species that experiences very high mortality rates in the wild?

Answer 7

produces litters of multiple offspring

Question 8

A trade-off exists between the number of offspring an organism can produce and the amount of care the organism can provide for its offspring. T or F and why

Answer 8

true; this is one of the inherent trade-offs in life history strategies.

Question 9

Which statement best describes a survivorship curve?

Answer 9

A survivorship curve reflects the relationship of survival rate with age.

Question 10

Mutations that cause sickness and death after reproduction:

Answer 10

can be passed on to future generations.

Question 11

When the hazard factor is low, individuals tend to:

Answer 11

age more slowly.

Question 12

In an experiment that doubled the average life span of fruit flies, the experimental methodology that worked involved:

Answer 12

waiting an extra week to collect eggs, thus ensuring that the parents of those eggs lived longer than average.

Question 13

The two essential elements of ecosystems are:

Answer 13

the biotic and abiotic environments.

Question 14

Which phrase best defines a biome?

Answer 14

areas with distinct plant communities and associated with particular climates

Question 15

Which statement best explains why the temperatures at the equator are warmer than at the North Pole?

Answer 15

The sun shines most directly on the equator and spreads out over a relatively small area.

Question 16

A rain shadow effect occurs:

Answer 16

when wind from the ocean passes over a coastal mountain to the other side.

Question 17

A driving force behind ocean currents is:

Answer 17

global wind circulation.

Question 18

What percentage of sunlight is converted to chemical energy through photosynthesis?

Answer 18

1%

Question 19

If there were 2,000 units of biomass among the primary producers of a food chain, how much biomass would be expected among the tertiary consumers in that same food chain?

Answer 19

2 units

Question 20

Which statement is true?

Answer 20

Carbon is a major constituent of phospholipids, ATP, and other energy-storing molecules.

Question 21

The nitrogen cycle is important biologically because:

Answer 21

nitrogen is a component of amino acids, proteins, and nucleic acids.

Question 22

Similar to nitrogen, phosphorus is often a limiting resource in soils, which constrains plant growth. Consequently, fertilizers usually contain large amounts of phosphorus.

Answer 22

Runoff into lakes spurs growth of large amounts of algae.

Question 23

Which of the following statement about a niche is true?

Answer 23

An organism’s realized niche is the subset of the fundamental niche in which the organism actually thrives.

Question 24

A species of moth with an 11-inch-long tongue feeds on the nectar from a species of orchid with an 11-inch-long nectar tube. In the same way, the orchids depend on the moths for pollination. This relationship is best described by the word(s):

Answer 24

coevolution.

Question 25

In a New England forest, different species of warbler birds were discovered that feed on things they find in or below the trees. The different bird species, which are nearly identical in most respects, all share the same niche. Yet they all thrive and reproduce successfully. How is this possible?

Answer 25

They feed on different parts of the same trees.

Question 26

The fire salamander can squirt a nerve toxin from glands on its back to deter predators. This is an example of:

Answer 26

a chemical defense.

Question 27

Which statement is true about parasites?

Answer 27

They can alter the behavior of their hosts.

Question 28

In a commensal relationship:

Answer 28

one species benefits while the other is neither benefited nor harmed.

Question 29

A glacier recedes, leaving behind bare rock. What is the first thing to occur?

Answer 29

Bacteria and fungi establish themselves.

Question 30

Keystone species:

Answer 30

play an unusually important role in determining the species composition in a habitat.

Question 31

The total economic value of an ecosystem:

Answer 31

includes all of the ecosystem services, future uses, and non-use values (such as cultural, intrinsic, and aesthetic values) of an ecosystem.

Question 32

Assessing biodiversity:

Answer 32

is not completely objective.

Question 33

Biodiversity hotspots are defined by the number of endemic species and:

Answer 33

degree of threat.

Question 34

The chances of a species going extinct are increased when its geographic range is _____________, its local population size is ______________, and its habitat tolerance is ______________.

Answer 34

restricted; small; narrow

Question 35

What does it mean to say that a species is “endangered”?

Answer 35

That species is in imminent danger of extinction.

Question 36

What does it mean to say a species is “threatened”?

Answer 36

That species is not in immediate danger of extinction, but it is vulnerable to extinction.

Question 37

Which description represents an irreversible disturbance?

Answer 37

extinction of the Chinese river dolphin

Question 38

In the United States, purple loosestrife is a(n):

Answer 38

exotic flowering plant that has caused significant problems for native species.

Question 39

Which of these is an indirect effect of acid rain?

Answer 39

the loss of calcium and potassium ions from the soil

Question 40

Global warming is caused mostly by:

Answer 40

the accumulation of greenhouse gases in the earth’s atmosphere.

Question 41

_______________ is responsible for the greatest loss of tropical forests.

Answer 41

Agriculture

Question 42

Ozone depletion allows ____________ to reach the earth’s surface.

Answer 42

short-wavelength ultraviolet light

Question 43

Which of the following statements about species preservation is true?

Answer 43

Saving one species may result in the endangerment of another.

Question 44

Which maxim is generally true of well-designed biological reserves?

Answer 44

A reserve with diverse habitats is better than a reserve with uniform habitats.

Question 45

Which of the following statement about plant evolution is true?

Answer 45

The tallest plants are 20 times taller than the tallest animals.

Question 46

Which of the following is true about monocots?

Answer 46

Monocots are a monophyletic group.

Question 47

In trees, the epidermis on the stem and roots is replaced by a protective covering of dead:

Answer 47

cork cells.

Question 48

Which of the following is a vital function that roots perform for a plant?

Answer 48

anchor plants to the ground

Question 49

The greatest amount of photosynthesis in a plant can be found in:

Answer 49

palisade mesophyll cells.

Question 50

In what region of the plant do cells divide rapidly by mitosis to provide for growth and expansion?

Answer 50

meristem

Question 51

Which of the following is true about water and plant leaves?

Answer 51

Leaves must allow some water vapor to escape through stomata in order to transport water from the roots into the leaves.

Question 52

Which statement about plant growth is true?

Answer 52

Much of what we know about plant nutrition has been derived from experiments with hydroponically grown plants.

Question 53

Plants do not grow well in pure clay soils because:

Answer 53

the soil packs so tightly it limits the amount of oxygen that can reach roots.

Question 54

Nitrogen fixation is an energetically costly process. What is the fuel that enables bacteria to split apart nitrogen molecules into a usable form for the plant?

Answer 54

sugars from the plant

Question 55

In mycorrhizal associations, the fungi benefit the plant by:

Answer 55

helping the plant grow faster and larger.

Question 56

Cohesion of water molecules in the xylem of a plant is a result of:

Answer 56

hydrogen bonds between the oxygen of one water molecule and a hydrogen of another water molecule.

Question 57

Many plants have flowers with sweet smells and captivating colors and shapes because:

Answer 57

animals are more likely to transport the plant’s male gametes to female gametes.

Question 58

Asexual reproduction is advantageous to plants because it:

Answer 58

is energetically efficient and faster than sexual reproduction.

Question 59

Which of the following is true about a sexually reproducing population?

Answer 59

More energy is required compared to asexual reproduction.

Question 60

In the life cycle of a non-flowering, non-seed plant (ferns), the process of meiosis produces:

Answer 60

spores

Question 61

Which structure on a flowering plant is the first to receive the pollen granules?

Answer 61

the stigma

Question 62

Which of the following is correct about plant gamete production?

Answer 62

The embryo sac arises through mitosis of megaspores.

Question 63

The embryo sac that forms within the ovule in a plant ovary forms from:

Answer 63

a diploid megaspore mother cell undergoing meiosis.

Question 64

How do wind- and water-pollinated plants increase their odds of pollination?

Answer 64

They produce tens of millions of pollen grains.

Question 65

The phrase “double fertilization” in angiosperms is best described by which of the choices below?

Answer 65

Each pollen grain contains two sperm cells and one leads to the fertilization that produces the embryo and the other leads to the fertilization that produces the endosperm.

Question 66

How does staggered maturation reduce self-fertilization?

Answer 66

Because gametes are ready at different times, the male gamete may be incapable of fertilizing the female gamete.

Question 67

In flowering plant reproduction, the _______________ develops into the fruit, and the _______________ develops into the seed.

Answer 67

ovary; ovule

Question 68

Some fruits are designed to be attractive food for animals. Other fruits that rely on animal dispersal are:

Answer 68

sticky or covered with clingy burrs.

Question 69

Seeds germinate only when levels of oxygen, water, and ________ are optimal.

Answer 69

temperature

Question 70

Which of the following regarding tree growth is true?

Answer 70

The vascular cambium produces wood.

Question 71

What happens to meristem cells that are left behind as the top of a plant grows higher?

Answer 71

They become dormant.

Question 72

Secondary xylem is the main component of:

Answer 72

wood

Question 73

Unlike animals, which produce each hormone _________________, plants produce hormones _________________.

Answer 73

in a specific part of the body; in many cell types

Question 74

Which of the following would be most useful to a farmer wanting to significantly increase the size of the radish plants grown on a farm?

Answer 74

gibberellins

Question 75

When auxin molecules move away from a light source and to the opposite (or more shaded) side of the plant, the result is the plant bends toward the light. Which specific action, stimulated by auxin concentration, results in this bending?

Answer 75

Auxins stimulate greater growth on the shaded side.

Question 76

The production of the plant hormone ethylene plays a major role in:

Answer 76

leaf death.

Question 77

In plants, abscisic acid:

Answer 77

maintains seed dormancy and winter dormancy and closes stomata.

Question 78

Phototropism and gravitropism are both a result of uneven distribution of:

Answer 78

auxins

Question 79

Which of the following is an important environmental cue that sets and resets a plant’s biological clock?

Answer 79

temperature cycles

Question 80

What can you conclude from these graphs about the environmental factor(s) that causes flowering in short-day plants?

Answer 80

Plants flower when the length of the night is increasing and falls within a certain range.