Science quarterly 1
the hypothesis
A new concept that is tested in a scientific investigation is known as
stopper the flask tightly to prevent evaporation of the solution
An unsafe procedure for heating a nutrient solution in a flask would be to
enzymes
Base your answer to the following question on the information below and on your knowledge of biology. Organisms living in a bog environment must be able to tolerate nitrogen-poor, acidic conditions. Bog plants such as the venus flytrap and sundew are able to obtain their nitrogen by attracting and consuming insects. These plants produce chemicals that break down the insects into usable compounds. the chemicals present in the plants that break down the insects are most likely
observe general trends in the data
Graphs of the data from laboratory investigations are used to
other researchers can replicate the experiment
a biologist reported success in breeding a tiger with a lion, producing healthy offspring. Other biologists will accept this report as fact only if
the dipeptide would digest slower or not at all
a process that occurs in the human body is shown in the diagram below dipeptide(substrate) + enzyme= enzyme-substrate complex + amino acids + enzyme. What would happen if a temperature change caused the shape of the active site to be altered
the scientist observed four deer in different locations at various times of the day
a scientist tested a hypothesis that white-tailed deer would prefer apples over corn as a primary food source. The findings of the test, in which the scientist claimed that the deer preferred apples, were published. Which research technique, if used by the scientist, might result in this claim being questioned
contained no tryptophan
a student wanted to investigate the effect of varying concentrations of tryptophan on a bacterial culture. Several cultures of the same bacterial species were grown on media, each with a different amount of tryptophan. The cultures were then incubated at 37 degrees C. At the end of 24 hours, the cultures were examined. As a control, the student should have used a culture that
2,000
a transparent metric ruler is placed on the stage of a microscope and observed under low power. The diameter of the field of vision was found to be 2 millimeters. How many micrometers is the diameter
regulation
after eating a meal, blood sugar levels are elevated. The body secretes hormones to help absorb excess sugar into cells and return blood sugar levels to normal. This is an example of
be able to be replicated to be accepted
all experiments must
working with chemicals, or heating liquids
always wear googles when
carbon, hydrogen, oxygen, and nitrogen
amino acids contain
control group and an experimental group
an experiment always has
fats and glycogen
animals store energy in the form of
excretion
as a result of their metabolic activities, many organisms produce harmful substances. These substances are eliminated by the process of
excretion
as a result of their metabolic activities, many organisms produce harmful substances. these substances are eliminated by the process of
have a ratio of hydrogen to oxygen of 2:1
carbohydrates
is not changed, it is the baseline you compare the experimental group(s) to
control group
reactions that are used to make proteins, lipids and polysaccharides
dehydration synthesis
variable that is being measured
dependent variable
saturated fats are solid at room temperature and all carbon to carbon bonds are single bonds. polyunsaturated fats are liquid at room temperature and have one or more double or triple carbon to carbon bonds
describe two chemical differences between saturated and polyunsaturated fats
specific for a given molecule or substrate. influenced by temperature and pH. Enzymes have an optimal temperature and pH, too hot or cold, too acid or basic the enzyme can lose its shape and function.
enzymes
metabolic activities
every single-celled organism is able to survive because it carries out
differs in only one variable from the control
experimental group
turns orange in the presences of monosaccharides
glucose indicator
maintaining a stable internal environment. examples include regulation of blood sugar, temperature and regulation of water loss by guard cells
homeostasis
it does not receive the experimental treatment(independent variable)
how does the control group setup in an experiment differ from the other setups in the same experiment
breaks down proteins, lipids, and polysaccharides
hydrolysis
the temperature is increased to 30 degrees C and the oh is increased to 9
if enzyme C is functioning at 25 degrees C and a ph of &, under which conditions would the rate of enzyme action probably increase
increasing temperatures altered the structure of catalase, decreasing oxygen production
if the temperature of the tissue samples used had been raised from 37 to 50, the results would have been different because
amino acids and proteins
if there were no nitrogen compounds in the soil, the most immediate effect on plants growing in that soil would be difficulty in synthesizing
iodine
in a chemical analysis of a sample of animal tissue, which element would most likely be found in the smallest quantity
water
in a living cell, which compound serves primarily as a substance in which most molecules and ions are dissolved
formulating a hypothesis
in a scientific investigation after the question is defined the next step is most likely
glycogen
in humans, excess glucose is stored as the polysaccharide known as
sources of stored energy and components of cellular membranes
in living organisms, lipids function mainly as
were the eating habits of the two groups similar
in teas, researchers gave a cholesterol-reducing drug to 2335 people and an inactive substitute (placebo) to 2081. Most of the volunteers were men who had normal cholesterol levels and no history of heart disease. After 5 years, 97 people getting the placebo had suffered heart attacks compared to only 57 people who had received the actual drug. The researchers are recommending that to help prevent heart attacks, all people(even those without high cholesterol) take these cholesterol-reducing drugs. In addition to the information above, what is another piece of information that the researchers must have before support for the recommendation can be justified
releases energy
in the cells of the human body, oxygen molecules are used directly in a process that
proteins
in what class of organic molecules would hemoglobin, insulin, albumin, and maltase, all of which are composed of chains of amino acids, be placed into
synthesis
in which process are simple materials chemically combined to form more complex materials
changed by the experimenter. it represents the idea that you are testing in your experiment
independent variable
do not contain both carbon and hydrogen. examples are water, carbon dioxide, and salt
inorganic compounds
carbon dioxide and water
inorganic molecules
atom, molecule, organelle, cell, tissue, organ, organ system, and organism
levels of organization
are made from glycerol and fatty acids
lipids
its activity would slow down
meat tenderizer contains an enzyme that interacts with meat. If meat is coated with tenderizer and then placed in a refrigerator for a short time, how would the enzyme be affected
sum of all chemical reactions in a cell
metabolism
carbohydrates
molecules consisting only of carbon, hydrogen, and oxygen atoms made up a large part of a plant cell wall. These molecules are classified as
chemical bonds
more energy can be released from a fat molecule than from a glucose molecule because the fat molecule contains more
both organic and inorganic compounds
most organisms contain
another person
never point an open test tube towards
a feedback mechanism for maintaining homeostasis
on hot, dry days, guard cells often close microscopic openings in plant leaves, conserving water. This is an example of
maintain internal stability
one characteristic of all living things is that they
determines how a protein folds. folding determines its shape. a proteins function depends on its shape
order of amino acids
always contain carbon and hydrogen, examples are carbohydrates proteins, lipids and nucleic acids
organic compounds
glucose
organic molecules
synthesis
organisms combine simple molecules to form complex molecules by the process of
acidic
pH from 1-7 indicates
basic
pH from 7-14 indicates
starch
plants store carbohydrates in the form of
protease
polypeptide +water then A= amino acids which substance is represented by letter a
are made of monosaccharides
polysaccharides
turns purple in the presence of proteins
protein indicator
made up of amino acids
proteins
change shape
shrimp that live in the cold waters off alaska will die if introduced into warm water . One likely reason these shrimp do not survive is that enzymes in the shrimp
their enzymes function best at a temperature of 70 or higher
some species of bacteria thrive in very hot springs because
turns blue back in the presence of polysaccharides
starch indicator (iodine)
what an enzyme reacts with. for example protease and proteins.
substrate
no metabolic activity present
the ability to grow in size is a characteristic of living organisms. Although an icicle may grow in size over time, it is considered nonliving because there is
draw a valid conclusion for that experiment
the analysis of data gathered during a particular experiment is necessary in order to
set the extra 5 ml aside in a labeled beaker and sk the teacher for advice
the directions for a laboratory activity call for 50 milliliters (ml) of solution A. A student accidentally takes 55 ml from the stock bottle. What should the student do with the extra 5 ml of solution A
10 to 12
the effect on the reaction rate of trypsin caused by a temperature change from 40 to 50 would be the most similar to the effect caused by a change in oh from
ATP
the energy used to obtain, transfer, and transport materials within an organism comes directly from
the amount of substrate W produced in five minutes at various pH levels
the equation below represents a chemical reaction that occurs in humans. Substrate X + Substrate Y =enzyme C = Substrate W. what data should be collected to support the hypothesis that enzyme C works best in an environment that is slightly basic
dehydration synthesis
the process by which glucose is converted to starch is known as
enzymes are denatured by excessive heat
the rate of photosynthesis is reduced at temperatures above 40 because
arrangement of amino acids in the protein
the shape of a protein is originally determined by the
the shape of a molecule determines how it functions in chemical reactions
the shape of each of the molecules is important because
boiling deactivates the enzyme responsible for converting sugar to starch
the sweet taste of freshly picked corn is due to the high sugar content in the kernels. Enzyme action converts about 50% of the sugar to starch within one day after picking. To preserve its sweetness, the freshly picked corn is immersed in boiling water for a few minutes, and then cooled. which statement most likely explains why the boiled corn kernels remain sweet
chains folded differently and a different sequence of amino acids
two proteins in the same cell perform different functions. this is because the two proteins are composed of which of the following
lipids
what is the major component of plasma membranes
2:1
what is the ratio of hydrogen atoms to oxygen atoms in a molecule of glucose
68%
what percentage of the human body is composed of inorganic material
the organism becomes ill or may die
what usually results when an organism fails to maintain homeostasis
repeating the experiment several times
which activity might help to increase the validity of this experiment
C12H22O11
which chemical formula represents a carbohydrate
c12h22o11
which formula represents an organic compound
H-N-H and oh-c--o
which groups are directly involved in the formation of peptide bonds
reproduction
which life function could be eliminated without affecting an individual rabbits ability to survive when food is scarce
starch-glycogen
which organic compound is correctly matched with the subunit that composes it
a lipid
which organic compound is produced when three fatty acid molecules bond to one glycerol molecule
an apple tree making its own food
which phrase is an example of autotrophic nutrition
make sure the balance weighs accurately before starting the measurement, and then record the weight for three trials and average the results.
which procedure is the most acceptable method for obtaining the accurate weight of a specimen in a laboratory experiment
photosynthesis
which process is a form of autotrophic nutrition
environmental conditions affect germination
which sentence represents a hypothesis
develop a hypothesis, select suitable laboratory materials, test the hypothesis, formulate a conclusion
which sequence of steps was most likely taken in this experiment
a current professional science journal article on the control of pathogens
which source would provide the most reliable information for use in a research project investigating the effects of antibiotics on disease-causing bacteria
only one independent variable is used for each experiment
which statement about the use of independent variables in controlled experiments is correct
it converts the food into energy for the cell
which statement best describes respiration within a cell
a theory refers to a scientific explanation that is strongly supported by a variety of experimental data
which statement best describes the term theory as used in the gene-chromosome theory
they are complex molecules made from smaller molecules
which statement describes starches, fats, proteins, and DNA
vaccinate 50 birds, do not vaccinate 50 other birds, and expose all 100 to the disease
which statement describes the best procedure to determine if a vaccine for a disease in a certain bird species is effective
the opening of the test tube is pointed towards the student and the student is not wearing goggles
which statement describes two unsafe laboratory practices
it may lead to explanations that combine data with what people already know about their surroundings
which statement most accurately describes scientific inquiry
enzymes are destroyed when they are used and must be synthesized for each reaction
which statements about enzymes is not correct
water
which substance plays a major role in most of the chemical reactions that occur in a living cell
metabolism
which term is defined as all the chemical reactions that are required to sustain life
a hypothesis may lead to further investigation even if it is disproved by the experiment
why do scientists consider any hypothesis valuable
millimeters
zebra finches are small black-and-white birds that lay eggs bout the size of a bean seed. Which unit of measurement is best for accurately measuring the length of these eggs
