Biology final
which term most precisely descries the cellular porcess fobreaage down large molecules into smaller ones
catabolism
what is the voltage across a membrane caleld
membrane potential
which of the following is true for nabolic pathways
they consume energy to buld up polymers form monomers
a system at chemical equilibrium
can do no work
proteins can be composed of how many different amino acids
20
how many electron pairs does carbon need to complete its valence shell
4
carbon dioxide is readily soluable in water according to the equation CO2 + H2O ↔ H2CO3. Carbonic acid (H2CO3) is a weak acid. Respiring cells release CO2 into the bloodstream. What will be the effect on the pH of blood as that blood first comes in contact with respiring cells?
Blood pH will decrease slightly, becoming slightly more acidic
which of the following statements concerning cells of the domains bacteria and archea is correct
DNA is present in both archea and bacteria
which organelle often takes up much of the volume of a plant cell
central vacuole
a strong acid like HCL
IONIZES COMPLETELY IN AN AQUEOUS SOLUITON
which of the following isan example of potential rather than kinetic energy
a molecule of glucose
what specific type of bond is formed when two amino acids are linked together by a dehydration synthesis reaction to form a dipeptide
a peptide bond
which of the followin effects is produced by the high surface thension of water
a water strider can walk across the surgace of a small pond
water molecules are able to for hydrogen bonds with.... a. compounds that have polar bonds b. oils c. oxygen gas molecules d. any ion
a. compounds that have polar bonds
Carbon-12 is the most common isotope of carbon and has a mass number of 12. However, the atomic mass of carbon is slightly more than 12 daltons. Why? Some carbon atoms in nature have more neutrons The atomic mass does not include the mass of electrons. Some carbon atoms in nature have an extra proton. Some carbon atoms in nature have undergone radioactive decay.
a. some carbon atoms in nature have more neurons
liquid water's high specific heat is mainly a consequence of the
absorption and release of heat when hydrogen bonds break and form
The main source of energy for producers in an ecosystem is .......... a. light energy from the sun. b. thermal energy from the sun. c. chemical energy. d. ATP.
a. the light energy from the sun
reactants capable of interacting to form products in a chemical reaction must first overcome a thermodynamic barrier known as the reactions
activation energy
the golgi apparatus has a polarity or sideness to its structure and function. which of the following statements describes this polarity
all of the above correctly descrie polar characteristicss of the golgi function
This functional group is called a .....................
amine or amino
all of the following are part of the prokaryotic cell except
an endoplasmic reticulum
lactose, a sugar in milk iscoposed of one glucose molecule joined by a glycosidic linkage to one galacose molecule. how is lactose classified
as a disaccharide
What is the maximum number of covalent bonds an element with atomic number 8 can make with hydrogen? 1 2 3 4
b. 2
All the organisms on your campus make up ................ an ecosystem. a community. a population. a domain.
b. a community
What results from an unequal sharing of electrons between atoms? a non-polar covalent bond a polar covalent bond an ionic bond a hydrogen bond
b. a polar covalent bond
Electrons exist only at fixed levels of potential energy. However, if an atom absorbs sufficient energy, from a souce such as heat or light, a possible result is that ....... an electron may move to an electron shell closer to the nucleus. an electron may move to an electron shell farther away from the nucleus. the atom may become a radioactive isotope. the atom would become a negatively charged ion, or anion.
b. an electron may move to an electron shell closer to the nucleus
Why is each element unique and different from other elements with respect to its chemical properties? Each element has a unique atomic mass. Each element has a unique number of protons. Each element has a unique number of neutrons. Each element has different radioactive properties.
b. each element has a unique number of protons
Imagine there is a species-specific fishing regulation that mandates only adult fish of this species that are 75 cm or longer may be kept and shorter fish must be released. Based on your knowledge of natural selection, you would predict that the average length of the adult fish population will ............ a. remain unchanged. b.gradually decline. c. rapidly decline. d. gradually increase
b. gradually decline
Which of these provides evidence of the common ancestry of all life? a. ubiquitous use of catalysts by living systems b.near universality of the genetic code c. structure of the nucleus d. structure of chloroplasts
b. near universality of the genetic code
Which of the following is the best description of a control for an experiment? a. Only the experimental group is tested or measured. b.The control group is matched with the experimental group except for the one experimental variable. c. The control group is exposed to only one variable rather than several. d. The control is left alone by the experimenters.
b. the control group is matched with the experimental group except the one experimental variable
the partial negative charge in a molecules of water occurs because... a. the oxygen atom acqures an additional electron b. the electrons shared between the oxygen and hydrogen atoms spend more time arond the oxygen aton'sm nucleus than around the hydrogen antoms nucleus c. the oxygen atom has 2 pairs of electrons in its valence shell that are not neutralized by hydrogen atoms d. one of the hydrogen atoms donates an electron to the oxygen atom
b. the electrons shared between the oxygen and hydrogne atons spend more tmie arojnd the oxygen atom's nucleus tan arond the gydrogen atom's nucleus
When applying the process of science, which of these is tested? a conclusion a result a hypothesis an observation
c. a hypothesis
Which of the following statements is false? Carbon, hydrogen, oxygen, and nitrogen are the most abundant elements of living matter. Some naturally occurring elements are toxic to organisms. All organisms require the same elements in the same quantities Iron is an example of an element needed by all organisms.
c. all organisms require the same elements in the same qantities
Prokaryotes are classified as belonging to two different domains. What are the domains? a. Bacteria and Eukarya b. Archaea and Monera c. Bacteria and Archaea d. Bacteria and Protista
c. bacteria and archaea
When two atoms are equally electronegative, they will interact to form ....... hydrogen bonds. polar covalent bonds. non-polar covalent bonds ionic bonds.
c. non polar covalent bonds
In presenting data that result from an experiment, a group of students show that most of their measurements fall on a straight diagonal line on their graph. However, two of their data points are "outliers" and fall far to one side of the expected relationship. What should they do? a. Do not show these points but write a footnote that the graph represents the correct data. b. Average several trials and therefore rule out the improbable results. c. Show all results obtained and then try to explore the reason(s) for these outliers. d. Throw out this set of data and try again. e. Change the details of the experiment until they can obtain the expected results.
c. show all results obtained and then try to explore the reason(s) for these outliers
A controlled experiment is one in which ............. a. the experiment is repeated many times to ensure that the results are accurate. b. the experiment proceeds at a slow pace to guarantee that the scientist can carefully observe all reactions and process all experimental data. c.there are at least two groups, one of which does not receive the experimental treatment. d. there are at least two groups, one differing from the other by two or more variables.
c. there are at least 2 groups, one of which does not receive the experimental treatment
the element present in every organic molecule is
carbon
which two functional groups are always foundin amino acids
carboxylic acid and amino
increasing the substrate concentration in an enzymatic reaction could overcome which of the following
competitive inhibition
if the pH of a sollution is decresed from 9to 8 it means that
concentration of G+ has increased tenfold and the concentration of OH- has decresed to one-tenth what they were at the pH of 9
Which of the following is (are) true of natural selection? a. It requires genetic variation only. b. It results in descent with modification. c. It involves differential reproductive success. d.all of the above are true
d. all of the above
Oxygen has an atomic number of 8 and a mass number of 16. Thus, what is the atomic mass of an oxygen atom? approximately 8 grams approximately 8 daltons approximately 16 grams approximately 16 daltons
d. approximately 16 Daltons
Which of the following types of cells utilize deoxyribonucleic acid (DNA) as their genetic material but do not have their DNA encased within a nuclear envelope? a. animal b. plant c. fungi d. bacteria
d. bacteria
About 25 of the 92 natural elements are known to be essential to life. Which 4 of these 25 elements make up approximately 96% of living matter? carbon, sodium, hydrogen, nitrogen carbon, oxygen, phosphorus, hydrogen oxygen, hydrogen, calcium, nitrogen carbon, hydrogen, nitrogen, oxygen
d. carbon, hydrogen, nitrogen, oxygen
Organisms interact with their environments, exchanging matter and energy. For example, plant chloroplasts convert the energy of sunlight to .............. a. the energy of motion. b. carbon dioxide and water. c. kinetic energy. d. Chemical energy from organic molecules
d. chemical energy from organic molecules
In what way are elements in the same column of the periodic table the same? They have the same number of protons. They have the same number of neutrons. They have the same number of electrons. They have the same number of electrons in their valence (outer-most) shell.
d. they have the same number of electrons in their valence (outer most shell)
Question 13 1 / 1 Why is it important that an experiment include a control group? a. The control group provides a reserve of experimental subjects. b. The researcher predetermines the results for the control group. c. A control group assures that an experiment will be repeatable. d. Correct! Without a control group, there is no basis for knowing e. if a particular result is due to the variable being tested.
d. without a control group there is no basis for knowing
what is the chemical reaction mechanism by which celss make polymers from monomers
dehydration synthesis reactions
which of the following best sumarizes the relationship between dehydration synthesis reactions and hydrosysis
dehydration synthesis reactiosn assemble polymers from monomers and hydrolysis reactions break down polymers into monomers
the molar mass of glucos is 180 g/mol. what porcedure sould you carry out to make a 1 M solution of glucose
dissovle 180 g of glucose in .8 L of water and then add more wateruntil the total vilume of the solution is 1 L
From its atomic number of 15, it is possible to predict that the phosphorus atom has ........ 15 neutrons. 15 protons. 15 electrons. 8 electrons in its outermost electron shell. 15 protons and 15 electrons
e. 15 protons and 15 electrons
What is the reason that a modern electron microscope (TEM) can resolve biological images to the subnanometer level, as opposed to the tens of nanometers achievable for the best super-resolution light microscope?
electron beams have much shorter wavelengths than visible light
An organism has been isolated from decomposing organic matter. This organism has a cell wall and a nucleus, but no chloroplasts. How would you classify this organism? a. domain Bacteria, kingdom Prokaryota b. domain Archaea, kingdom Bacteria c. domain Eukarya, kingdom Plantae d. domain Eukarya, kingdom Protista e. domain Eukarya, kingdom Fungi
e. domain eukarya, kingdom fungi
the presence of cholesterol in the plasma membranes of some animal
enables the membrane to stay fluid more easily with cell temperature drops
A chemical reaction that has a positive ΔG is best described as ............
endergonic
which of the following is a statement of the first law of thermodynamics
energy can not be created or destroyed but it can be converte form one form to another form of energy
whenever energy is transformed, there is always an increase in the
entropy of the universe
which of the following statements regarding enzymes s true
enzymes increase the rate of a reaction by lowering the activation energy barrier
Glucose diffuses slowly through artificial phospholipid bilayers. The cells lining the small intestine, however, rapidly move large quantities of glucose from the glucose-rich food into their glucose-poor cytoplasm. Using this information, which transport mechanism is most probably functioning in the intestinal cells?
facitiltated diffusion
starch is a polyaccharide composed of ________________ monosaccharides linked together by glycosidic bonds
glucose
which of the following is not a polymer
glucose
why does ice float in liquid water
hydrogen bonds stabilize and the molecules of the ice farther apart and less dense thatn the water molecules of liquid water
the active site of an enzyme is the region that
is involved in the catalytic reaction of the enzyme
which of the following statements is correct about diffusion
it is a passive process in which molecuoles more from a region of hgher concentration to a region of lower concentration
a compound contains hydroxyl groups as its predominant functional group. whichof the folowing statements is tre concerning this compound
it is a polar molecule and should dissolve in water
when chemicla transport of mechanical work is done by an organism, what happens to the heat generated
it is lost to the envrionment
why is ATP an inmortant molecule in metabolism
it provides energy coupling between exergonic and endergonic reactions
why isn't the mitochondiron classified as part of the endmembrane system
its structure is not derived from the er or golgi
what takes place as an ice cube cools a drink
kenetic energy in the drink decreases
hydrolytic enzymes must be segregated and packaged to prevetn general destruction of cellular components. in animal cells, which of th efollowin organelles contain these hydrolytic enzymes
lysosomes
which of the following is true of metabolism is its entirely in all organisms
metabolism consists of all the energy transformation reactions in an organism
movement of vesicles within the cell depends on what cellular structures
microtubuoles and motor proteins
Which of the following is characterized by a cell releasing a signal molecule into the environment, followed by a number of cells in the immediate vicinity responding?
paracrine signaling
which of the following types of molecules are the major components of the cell membbrane
phospholipids and proteins
the difference between pinocytosis and receptor-mediated endocytosis is that
pinocytosis is nonselective in the molecules it brings into the cell, whereas receptor-mediated endocytosis offers more selectivity.
A localized group of organisms that belong to the same species is called a .......... a. biosystem. b. community. c. population. d. ecosystem.
population
large numbers of ribosomes are preset in cells that specialize in producin which of the following macromolecules
proteins
proton pumps are used in various ways by members of every domain of orgainisms: bacteria, archaea, and eukarya. wht does this most probaby mean?
proton gradients across a membrane were used by cells that were the comon ancestor fo all three domains of life
the primary objective of cell fraction is to
separate the major organelles so that their particular functions can be determined
themovement of the hydrophobic gas nitrus oxide into a cell is an example of
simple diffusion across the membrane
what kinds of molecules pass through a cell membrane most easily
smal and hydrophobic molecules like gasses
the liver is involved in detoxification of many poisons and drugs. which of the following structures is primarily involved in this process and therefore abundant in liver cells
smooth endoplasic reticulum
the type of organelle or structure is primaily involved in the synthesis of oils,, phospholipids, and steroids
smooth endoplasmic reticulum
when a plant cells, such as those found in a stalk of celery, is submerged in a very hypotonic solution, what is likely to occur
the cell will become turgid and stiff
the complexity and variety of organic molecules is due to
the chemical versatility of carbon atoms in that they cann bond with other carbon atoms
which of the following is a reasonalbe explanatin for why unsaturated fatty acids help keep any membrane more fluid in lower temperatures
the double bonds form kinks in the fatty acid tails, preventing adjacent lipids from packing tightly
Celery stalks that are immersed in fresh water for several hours become stiff and hard. Similar stalks left in a 0.15 M salt solution become limp and soft. From this we can deduce that ..............
the fresh water is hypotonic and the salt solution is hypertonic to the the cells of the celery stalks
why are hydrocarbons insoluble in water
the majority of their bonds are non polar covalent carbon to hydrogen linkages in which the electrons are equally shared
which of the following is a major cause fot eh size limits for certain types of cells
the need for sufficient surface area to support the cell's metaolic needs
for living organisms, which of the following is an inportant eonsequence of the first law of thermodynamics
the organism ultimately must obtain all of the necessary energy for life fomr its environment
which structure is the site of syntheis of proteins that may be exoorted from the cell
the rought endoplasmic reticulum
what determines whether a carbon antom's covalent bonds to other atoms are in a tetrahedral configuration of a planar configuration
the presence of absence of doble bonds between tghe carbon atom and other atoms
which of the following statements is true about enzyme-catalyzed reactions
the reaction is faster than the same reaton in the absence of the enzyme
which of the following is ture for all exergonic reactions
the reaction proceeds with a net release of free energy
according to the fluid mosaic model fo cell membranes, which of the following is a true statemtn about membrane phospholipids
they can move literally alon te plane of the membrane
the primary function of polysaccharides attached to the gycoproteins and glycolipids of animal cell membranes
to mediate cell to cell recognition
when biologist wish to study the internal ultrastructure of cells they can achieve the finest resolution by using a
transmission electronic microscope (tem)
Mammalian blood contains the equivalent of 0.15 M NaCl. Seawater contains the equivalent of 0.45 M NaCl. What will happen if red blood cells are transferred to seawater?
water will leave the cells, causing them to shrivel and collapse