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129 Cards in this Set

  • Front
  • Back
The work of a scientists begins with
careful observation
In science, a hypothesis is useful only if
it can be tested
Hypotheses may arise from
all of the above; logical inferences, imaginative guesses, prior knowledge
A controlled expierment allows the scientist to isolate and test
a single variable
The ability to reproduce resluts is an important part of any
expierment
The three particals that make up an atom are
protons, neutrons, and electrons
The space surronding the nucleus of an atom contains
electrons
The nucleus is made up of
protons and neutrons
Isotopes are atoms of the same element with the same number of protons and
the same number of neutrons
Which of the following makes up a molecule of water
two atoms of hydrogen and one atom of oxygen
A covalent bond is formed as a result of
sharing an electron pair
Ice floats on water because
water expands when it freezes
The most abundant compound in most living things is
water
A solution is an
evenly distributed mixture of two or more substances
When salt is dissolved in water, water is the
solvent
Which of the following organic compounds is the main source of energy for living things
carbohydrates
The combined portions of Earth in which all living things exist is called the
biosphere
The simplest grouping of more than one kind of organism in the biosphere is
a community
The lowest level of environmental complexity that includes living and nonliving factors is the
ecosystem
Which of the following is not a basic method used by ecologistts to study the living world?
classifying
What is the original source of almost all the energy in most ecosystems
sunlight
What is an organism that only feeds on plants called
herbivore
All the interconnected feeding relationships in an ecosystem make up a food
web
The repeated movement of water between Earth's surface and the atmosphere is called
the water cycle
Nitrogen fixations is carried out primarily by
bacteria
Climate is a global factor that produces
a wide range of environmental conditions that shapes communities
The average year after year conditions of temperature and precipitation region is the region's
climate
Temperatures on Earth remain within a suitable range for life as we know it because of the
greenhouse effect
The greenhouse effect is a
natural phenomenon that maintains earth's temperature range
A mountain can affect climate by
causing precipitation to fall mostly on one side of the mountain
Which has become the most important source for enviroment change on Earth?
human activity
Carbon dioxide is released into atmosphere by all the following except the
depletion of the ozone layer
In the very distant past, most people
lived in small groups
one of the goals of conservation bioligy is to
all of the above; manage natural resources, enforce enviromental laws and protect habitats
What is meant by "a library of genetic information" in reference to biodiversity?
all living organisms contain genetic information upon which humans can draw for future use.
An endagered species is
a group of organisms near extinction
One of the greatest threats today to biological diversity is
habit destruction
Protecting ecosystem diversity is a goal of c
conservation bioligy
An old growth forest is
a nonrenewable resource
The sum total of the genetically-based variety of living organisms in the biosphere is called
biodiversity
Early hunters and gathers in North America are responsible for
a major extinction event of large animals
Why are fossil fuels nonrenewable?
They require hundreads of millions of years to form
As DDT moves up the trophic levels in food chains, or food webs, its concentration
increases
The goals of conservation bioligy include all of the following except
introducing foreign spieces into new enviroments
Land is a resource that provides
all of the above; space for cities and suburbs, raw materials for industry, soil for growing crops
Which of the follwoing is NOT one of the factors that play a role in population growth rate
demography
One of the main charecteristics of a population is its
geographic distribution
Which of the following tells you population density?
the number of bacteria per square milimeter
The movement of organisms into a given area from another area is called
immigration
When orgainisms move out of a population, this is known as
emigration
Which are two ways a population can decrease in size
decreased birthrate and emigration
When individuals in a population reproduce at a constant rate, it is called
expnetial growth
As resources in a population become less availible, population growth
reaches carrying capacity
Which factor might NOT contribute to an exponetial growth rate in a given population
reduced resources
If the poulation grows larger than the carrying capacity of the enviroment, the
death rate may rise.
Demography is the scientific study of
human populations
Demograohic transition is change from high birthrates and high death rates to
a low birthrate and low death rate
The human population expierence exponential growth after
the industrial revolution began
The anticipated human population by the year 2050 is about
9 billion
The symbiotic relationship between a flowe and the insect that feeds on its nectar is an example of
mutualism because the flower provides the insect with food, and the insect pollinates the flower
An organisms niche is
the way the organism uses the range of physical and biological conditions in which it lives
The chemistry of aquatic ecosystems is determined by the
amount of salts, nutrients, and oxygen dissolved in the water
The unequal heating of the Earth's surface
all of the above, drives wind and ocean currents, has important effects on Earth's climate regions, and cause winds that transport heat throughout the biosphere
What is one difference between primary and secondary succesion
secondary sucession begins on soil and primary succession begins on newly exposed surfaces
All of the following contribute to the Earth's climate EXCEPT
biomes and ecosystems
Ponds and lakes are
standing-water ecosystems
The photic zone
extends to a depth of about 200 meters
Earth has three main climate zones because of the differneces in latitude and
angle of heating
No two species can occupy the same niche in the same habitat at the same time
because of the competitive exclusion principle
The branch of bioligy dealing with interactions among organisms and between organisms and their enviroment is called
ecology
An organism that cannot make its own food is called a
heterotroph
Green plants are
producers
Matter can recycle through the biosphere because
biological systems do not use up matter, they transform it
Organisms that obtain nutrients by breaking down dead and decaying plants and animals are called
decomposers
What animals eat both producers and consumers
omnivores
If a reaction in one direction releases energy, the reaction in the opposite direction
absorbs energy
What is the process that changes one set of chemicals into another set of chemical?
chemical reaction
Suspensions are mixtures
of water and undissolved material
In chemical reactions, atoms are
rearranged
The small dense region in the nucleus where the assembly of ribosomes begins is called the
nucleolus
The hollow tubes of protein, about 25 nanometers in diameter, that help maintain the shape of the cell are called
microtubules
Which organelles can use energy from sunlight to create energy-rich food molecules?
chloropasts
What is the process by which material is taken into the cell by infolding of the cell membrane?
endoctosis
The fourth and highest level of organization in multicellular organism is
an organ system
The Calvin cycle is another name for
light-independent reactions
Where are photosystems I and II found?
in the thylakoid membrane
Organisms that cannot make their own food and must obtain energy from the foods they eat are called
heterotrophs
A granum is a
stack of thylakoids
Organisms, such as plants, that make their own food are called
autotrophs
Most plants appear green because chlorophyII
does not absorb green light
The stroma is the space that surronds
thylakoids
Which of the following id NOT an example of a heterotroph
grass
Jan van Helmont concluded that plants gain most of their mass from
water
Where do the light-dependent reactions take place?
in the thylakoid membranes
Plants gather the sun;s energy with light-absorbing molecules called
pigments
Which of the following is an autotroph?
tree
Which of the following are used in overall reactions for photosynthesis?
carbon dioxide, water, light
Plants take in the sun's energy by absorbing
sunlight
Photosynthesis uses sunlight to convert water and carbon dioxide into
oxygen and high-energy sugars
Animal cells cannot carry out
alcoholic fermenatation
In the Krebs cycle
pyrivic acid is broken down into CO2 and H20
In cellular respiration, the final electron acceptor is
water
In glycolysis, each glucose molecule is broken down into
two molecules of pyruvic acid
The first set of reactions in cellular respiration is
glycolysis
Which compounds are produced by the two main types of fermentation?
alchohol or lactic acid
The energy that is released during cellular respiration is stored as
ATP and NADH
Each of the following processes realses energy from glucose EXCEPT
photosynthesis
The most important product of the electron transport chain in cellular respiration is
NAD+
Cellular respiration benefits organisms by
transferring energy to ATP
As a cell becomes larger, its
volume increases faster than its surface area
The process by which a cell divides into two daughter cells is called
cell division
When during the cell cycle are chromosomes visible
only during cell division
Name three phases in the cell cycle
G1 phase G2 phase M phase
When during the cell cycle is a cell's DNA replicated
S phase
The cell cycle is the
series of events that cells go through as they grow and divide
The two main stages of cell division are called
cytokinesis and mitosis
Cancer is a disorder in which some cells have lost the ability to control their
growth rate
Cancer cells form masses of cells called
tumors
In eukaryotic cells, the timing of the cell cycle is regulated by
cyclins
What animals eat both producers and consumers
omnivores
If a reaction in one direction releases energy, the reaction in the opposite direction
absorbs energy
What is the process that changes one set of chemicals into another set of chemical?
chemical reaction
Suspensions are mixtures
of water and undissolved material
In chemical reactions, atoms are
rearranged
The small dense region in the nucleus where the assembly of ribosomes begins is called the
nucleolus
The hollow tubes of protein, about 25 nanometers in diameter, that help maintain the shape of the cell are called
microtubules
Which organelles can use energy from sunlight to create energy-rich food molecules?
chloropasts
What is the process by which material is taken into the cell by infolding of the cell membrane?
endoctosis
The fourth and highest level of organization in multicellular organism is
an organ system