Final Flashcards
catalysts enable reactions to take place faster by
they lower the amount of activation energy needed for the reaction to occur
if the products of a chemical reaction contain less energy than the reactants, the reaction must
involve the release of energy
a series of chemical reactions that results in the creation of a new biological molecule
is called a biochemical pathway
heterotrophs are organisms that
must consume other organisms for energy
the energy that is stored in food molecules and used by organisms
is held primarily by protons of hydrogen atoms
energy barring electrons may be transferred from one enzyme catalyzing a reaction to a different enzyme catalyzing a different reaction within a cell by
coenzyme
an important example of a coenzyme that functions in metabolism is
NAD
factors that allow a cell to control when an enzyme is active may include
all the above
energy is required for a variety of life processes including
all the above
the statement that energy can neither be created or destroyed, but can be changed in form is
the first law of thermodynamics
which of the following situations is most stable?
four tennis balls lying on the ground
a reaction in which the products have less energy than the reactants is
an exergonic reaction
which of the following reactions does not represent a form of energy
water
oxidation-reduction reactions are important in organisms because
they allow the passes of energy from molecule to molecule
t/f
the products of an endergonic chemical reaction possess more energy than the reactants from which they are produced.
true
t/f
without enzymes, chemical reactions necessary for life would not occur at a rate sufficient to sustain life.
true
t/f
overproduction of a certain product in biochemical pathways in a cell can be prevented by feedback inhibition.
true
t/f
energy of motion is often referred to as potential energy.
false
t/f
when a person uses food as a source of energy to run a race, energy is converted from chemical to mechanical form.
true
organisms that harvest energy from either sunlight or chemicals to make food molecules are called ___.
autotrophs
the energy needed to break existing chemical bonds storing the initiation of a chemical reaction is called ___.
activation energy
when an enzyme’s ___ changes, its activity changes.
shape
substances that are the ingredients for reactions are called ___, while the new substance that is formed are called ___.
reactants
products
the loss of electrons from a molecule is called ___, while the gain of electrons from a molecule is called ___.
oxidation
production
the portion of an enzyme into which a specific substrate can fit is called the ___.
active site
a ___ reaction is an endergonic reaction in which an enzyme catalyzes. an enzyme attaches to both an ATP molecule and a reactant. a single enzyme catalyzes both the splitting of ATP and the attachment of a phosphate group to the reactant.
coupled (reaction)
because there are a /couple/ of reactions they are talking about
an enzyme that may change its shape when it combines with a signal molecule is called a ___ enzyme.
allosteric
name an energy or energy-carrying molecule formed by each process:
photosystem I
photosystem II
the electron chain following the Krebs cycle
glycolysis
NADPH
ATP
ATP
ATP or NADH or pyruvate
what are molecules that can have electrons boosted to higher energy level when light particles hit them?
chlorophyll or pigments
stacks of thylacoid called ___ are found suspended in the stroma of chloroplasts.
grana
the complete range of radiant energy forms is called the ___ ___ ___.
electro magnetic spectrum
as protons leave the thylakoid via ATP synthethase, what is generated?
ATP
The ___ ___ is a series of biochemical reactions that uses ATP and NADPH to attach hydrogens and their high energy electrons to carbon obtained from carbon dioxide to form glucose molecules.
calvin cycle
light energy consists of tiny packets of energy called ___
photons
___ serves as the final electron acceptor for the electron transport chain of oxidative respiration.
oxygen
all organic colecules contain carbon atoms. the carbon atoms can ultimately be traced back in the food chain to ___.
carbon dioxide from the atmosphere
what happens when a chlorophyll molecule absorbs a photon of light ?
some of its electrons are raised to higher energy levels
feedback inhibition of cellular respiration
involves the allosteric binding of ATP
based on the cycle of cellular respiration, one can say the ultimate source of energy for all living things on earth is
the sun
the energy used in the calvin cycle for the production of carbohydrate molecules comes from
energy molecules ATP and NADPH that come from the photosystems
because of photosynthesis
the atmosphere is rich in oxygen gas
chemical energy stored in food molecules is released through
cellular respiration
light energy is converted to chemical energy through the process of
photosynthesis
if oxygen is absent during the second stage of cellular respiration
fermentation will occur
when water molecules are split to produce electrons needed to replace those lost by photosystem II during photosynthesis
oxygen is released
what is the name of the following process:
CO2 + H2O + light energy = CH2O +O2 (C6H12O6)
photosynthesis
NADP is important for photosynthesis because it
carries hydrogen atoms and energy for producing organic molecules
which of the following is not part of cellular respiration
the Calvin cycle
cells produce ATP molecules efficiently in the presence of
oxygen
oxidative respiration follows glycolysis when ___ is available
oxygen
the process of cellular respiration
breaks down food molecules to release stored energy
photosynthesis and cellular respiration are said to form a continuous cycle because
the products of one are the starting materials for the other
t/f
carbohydrates are important parts of an organism’s diet because they are the only molecules that can yield enough energy to produce ATP during cellular respiration.
false
t/f
in the last stage of photosynthesis, ATP and NADP power the synthesis of organic molecules using oxygen from water.
false
t/f
metabolic processes that require oxygen are called anaerobic.
false
t/f
when light hits a plant, all of the wavelengths are absorbed and used to make sugar.
false
t/f
photosynthesis is an endergonic process.
true
t/f
almost every oxygen molecule in the air was produced by photosynthesis.
true
t/f
an autotroph is able to make its own molecule
…?
… nutrients is called what
cycling
precipertation and evaporation are important components of
water cycle
the level of phosphorus in freshwater ecosystems
may change as a result of human activity
all organisms that live in a particular place at a particular time make up a what
community
succession is
a regular progression of specie placement in an environment
which of the is part of the nitrogen cycle?
all the above
in an ecosystem, producers may include
trees, grass, and shrubs
animals that feed on plants are at least in the what
second trophic level.
food webs are more commonplace than food chains because
organisms almost always eat and are eaten by many different organisms
the increase in carbon dioxide in our atmosphere over the last 150 years was caused primarily by
the burning of fossil fuels
going from one trophic level to the next higher level
the amount of useable energy always decreases
nitrogen fixation is best described as
conversion of atmospheric nitrogen into a form usable by living organisms
___ is the absorption and incorporation of nitrogen into plant’s components.
assimilation
at each trophic level, the energy stored by organisms is about ___ of that stored by at the level below.
10%
what is the production of ammonia by bacteria during the decaying of nitrogen-containing organic wastes
ammonification
in 1866 the German biologist Ernst Hankle gave the name of the study of how organisms fit into their environment, calling it ___
ecology
___ is water that is retained below the surface of the earth
groundwater
the primary productivity of an ecosystem is measured of the amount of organic matter that the ___ organisms of an ecosystem produce
producers
organisms that obtain their energy from organic wastes and dead bodies at all energy levels in an ecosystem are called ___
detritivores or decomposers
organisms that eat only plants are called ___
herbivores
much of the water cycle is powered by energy from ___
the sun
organisms that eat both plants and animals are called ___
omnivores
the total dry weight of all organisms in an ecosystem is called the ___
biomass
an energy pyramid shows the amount of energy contained in bodies of organisms at each ___ level
trophhic
plants lose water through a process known as
transpiration
t/f
all organisms in an ecosystem are part of the food web of that ecosystem.
true
t/f
decomposers absorb energy from organisms by breaking down living tissue
false
t/f
the lowest trophic level of any ecosystem is occupied by producers
true
t/f
phosphorous is often found in detergents and fertilizers
true
t/f
nitrogen gas makes up 79% of the earth’s atmosphere
true
t/f
ecologists call the physical location of a community its habitat
true
t/f
the difference between primary succession and secondary succession is that primary succession occurs only on land and secondary succession occurs in ponds and lakes
false
t/f
detritivores are especially harmful to an ecosystem
false
CFCs destroy ozone because the ultraviolet radiation breaks the bonds of CFCs and the
the free chlorine atoms catalyze and break down ozone
the decrease in specie diversity in some lakes in the NorthEastern US during the 20th century made be best explained by
acid rain
in the upper atmosphere, sulfur released from the burning of sulfur-rich coal combines with oxygen to form what
sulfur trioxide
destruction of the ozone layer may be responsible for the increase in
all the above
the heat-trapping ability of some gases in the atmosphere can be compared to
the way glass traps heat in a greenhouse
the extinction of species
has been speeded up by the activities of people
the destruction of tropical rainforests
all the above
the current rate of population growth will result in doubling world population every 38 years. with the current population 7 billion, what will be the approximate world population in 2055 if nothing is done to change this rate?
14 billion.
ozone shields the earth from the harmful effects of
ultraviolet rays
once pollution enters ground water
there’s no cost-effective way to remove it
most water pollution is caused by
agriculture
the greatest extinction of species is happening in the ___ biome.
tropical rainforest
the heat-trapping ability of carbon dioxide methane oxide in the atmosphere is known as the what
greenhouse effect
a great deal of water is found beneath the soil within porous rock reservoirs called
aquifers
carbon dioxid, soot, and ___ are three pollutants produced by the burning of coal.
sulfer
t/f
one of the evironmental benefits of CFCs is that they are stable.
true
t/f
one of the environmental problems of CFCs is that the are stable
true
t/f
pollution is no longer considered a major problem largely because of increase public concern and stringent regulation in industrialized developing countries.
false
t/f
one approach to producing pollution is to have government give money to industries that cause pollution.
false
t/f
the human birth rate has remained the same for the last 350 years.
true
t/f
there is nothing an individual can do to effect the environmental problems because the problem is too large and complex
false
t/f
there is no known way to reduce the emmissions of sulfur dioxide from the burning of coal into the air
false
t/f
the population of Earth has not changed much over the last 350 years
false
t/f
the world’s climate is warming because large amounts of CFCs are released into the atmosphere.
false
t/f
chromatids separate from each other during telophase.
false
t/f
meiosis results in the formation of haploid cells from diploid cells
true
t/f
nondisjuction, if it occurs, takes place during prophase II of meiosis.
false
t/f
gametes are diploid so that when fertilization occurs the resulting zygote will have the charateristic number of chromosomes
false
*refer to the AB meiosis/mitosis diagram *
which of these cells is in the process of diving to form gametes?
which of the cells will be diploid at the end of cell division?
B (can count and see that there’s only gonna be 2 chromosomes in each cell)
A
in order to fit within a cell, DNA becomes more compact by
wrapping tightly around associate proteins
a diploid cell is one that
all the above
diploid is to somatic as haploid is to
gamete
a mutation caused by a piece of DNA breaking away from its chromosome and becoming attached to a non-homologous chromosome
translocation
if nondisjunction occurs,
a gamete will receive too few or too many homologues
which of the following is the correct sequence of the cell cycle
G1 –> S –> G2 –> M –> C
homologous chromosomes are pairs of chromosomes containing genes that code for
the same traits
separation of one homolog from the other occurs during
anaphase I
a condition in which a diploid cell is missing a chromosome is called ___
monosomy
binary fission
is a process by which bacteria reproduce
in human sexual reproduction, a male haploid gamete and a female haploid gamete unite to form a ___
zygote with 46 chromosomes
the process of meiosis produces
four haploid cells
following replication of its DNA, each chromosome contain two ___ which are attached to each other by a centromere
chromotids
Collectively, the time spent in G1, S, and G2 is called ___
Interphase
chromosomes coil up and become shorter and thicker during
prophase
cables made of microtubules that extend from the poles of a cell to the centromere of chromosomes are called ___
spindle fibers
a photo of the chromosomes of a somatic cell undergoing mitosis can be used to detect down syndrome is called ___
a karyotype
a sequence of nucleotides of a DNA molecule that codes for a sequence of amino acids are called ___
a gene
the process called ___ guarantees the number of chromosomes of gametes is half the number of chromosomes found in ___ cell.
meiosis
somatic
the stage of meiosis during which homologs line up in pairs but on opposite sides of the equator of the cell is called ___
metaphase I
the cells resulting from meiosis in either males and females are called ___
gametes
when arms of two hologous chromosomes exchange reciprocol segments of DNA, ___ is said to have occured
crossing over
the 22 pairs of chromosomes in human somatic cells that are the same in males and females are called ___
autosomes
