semester 1 test & quizzes

What is typically the first step in the scientific method?

observation

The scientific method ________.

is a rough recipe for answering questions, but while the steps are best done in order they need not be performed in the same order as outlined nor must every step be performed every time since not every scientific field is the same.

A recent commercial advertised for a wristband that claimed to restore health and balance by taking advantage of natural frequencies of your biofield. It even showed several people struggling to balance first without the wristband and then balancing fine with the wristband. For only $20 plus shipping and handling this device can be yours. Why should you be skeptical of the claims made in this ad?

It was not a controlled experiment.

A current trend among professional baseball players is wearing braided titanium necklaces. The titanium reportedly regulates the flow of energy through the body. The player wearing the necklace then improves strength, tires less, and recovers more quickly.


If you were to evaluate these claims using the scientific method, what would be the first step?

Develop a hypothesis.

A current trend among professional baseball players is wearing braided titanium necklaces. The titanium reportedly regulates the flow of energy through the body. The player wearing the necklace then improves strength, tires less, and recovers more quickly.


Which of the following would be the strongest evidence for or against the necklace's effectiveness?

A bar graph comparing batting averages of the players who wear the official titanium necklace and those who were unknowingly wearing a fake titanium necklace

What should one do if the results of the experiment consistently do not support the original hypothesis?

Reject the original hypothesis and formulate a new hypothesis.

Gathering information just to add to the knowledge base, such as measuring the beak length of various bird species, is known as ________.

discovery science

What does the term "theory" mean to a scientist?

A collection of accepted hypotheses that explain a wide range of natural phenomena

Which of the following statements about the scientific method is false?

The scientific method proves things true.

In a controlled experiment, the researcher typically manipulates one variable, called the independent variable, to determine how this variable affects the final outcome, called the dependent variable. In the following hypothetical example, a researcher applies varying amounts of fertilizer (0, 2, 4, 8, 10 units) to potted tomato plants. All other variables that may affect the outcome (watering, temperature, sunlight, plant size, etc.) are kept the same from pot to pot. At the end of the growing season, the tomatoes grown on each plant are weighed to determine which fertilizer level produces the largest tomato yield. Which variable was the independent variable and which was the dependent variable?

Independent = Fertilizer amount, Dependent = Yield

Describe the steps you might take to graph the following information appropriately. Think about the process you would think through to make a correct graph and describe what you would do. You can make a list.

1. Determine what kind of graph to use by looking at the x-axis. If it is numerical, it is a scatterplot. If it has categories, it will be a bar graph. Because the x-axis has categories, the graph will be a bar graph.

2. To determine to scale to use when graphing, you use an equation. This will make sure you use 70% of the area of the graph. To do this, subtract the smallest numerical value from the largest, divided by the number of squares given on one of the axes. Round this answer to the most convenient number (always rounding up). Do this for both the x and y axes.

3. The x-axis will have three bars (1,2,3) and will be labeled "Brassica species". The y-axis will have numerical values determined by the calculated scale. The y-axis will be labeled "petal size" and the unit is mm.

4. Plot the information from the table onto the graph. Do not make the bars skinny. You can shade the bars, but make sure to use shades of white, gray, and black. Refrain from colors.

____ means judging information before accepting it as fact.

As a result of experimentation,

a new biological principle could emerge. ,more hypotheses may be developed. ,more questions may be asked. ,entire theories may be modified.

In an experiment, the control group is

treated exactly the same as the experimental group, except for one variable.

Which of the following can be changed based on new evidence?

theory ,experiment ,prediction ,hypothesis

Science is ______.

the inquiry-based effort to describe and explain nature

A hypothesis is a(n) ______.

tentative explanation

Science is limited to that which is _________.

both observed and testable

What would not be a good question to ask in the critical thinking process?

If everyone else believes it, shouldn’t I believe it too?

What is NOT true about science?

Science is the systematic study of the supernatural

What is a scientific theory?

a longstanding hypothesis used for prediction

Which question would be best for use in the scientific method? Your observation is when eating food with cayenne pepper people get stomach cramps.

Does cayenne pepper cause digestive problems in all people?

When you test more than one variable, such as butterflies having wing spots and also sounds for protection, how does that affect an experimental set up?

It causes an experiment to become more complicated to test every variable in combination

In a scientific experiment, the control group ______.

serves as a basis of comparison with the experimental group

You try to start your car, but it does not start. Which of these is a hypothesis?
Correct!

My car's battery is dead.

Which is a graph type you should not use?

Pie Chart

True or False: When studying humans, isolating a single variable is not often possible.

True

Scatter plots are used for which of the following types of data?

continuous data and data that is used to show trends

What is true for graphs?

You should always label the axis titles

Why do we need to display data in graph format?

Displaying data helps to detect the causes of our observations

What is sampling error?

the error that results from a non-representative sample that skews data from the true results

How can sampling error be avoided?

use a large sample size

What is true about absolute truth in terms of science?

it would require infinite number of tests

In this graph, please interpret what the data is showing. Pay attention to the point value of this question.

By looking at the graph, you should determine the independent and dependent variables. The independent variable is on the x-axis-- length (cm). The dependent variable is on the y-axis-- belly width (cm). This scatterplot graph is showing the relationship between the length of an alligator and its belly width. The longer the alligator is in cm, the wider the belly of the alligator is in cm.

In this graph, what is being compared?

Types of activities

If graphing this information for 2013, what type of graph would you make?

bar graph

What is the independent variable for this set of data?

Driver

You are studying how far in miles that Monarch Butterflies each year over a 10 year period. What would be the type of graph you should use to show this data and what variable would be on the x and y axes? Include the units for the variables where needed.

A line or scatter plot would be used to show this data. The independent or x-axis would be labeled "time" and the unit would be in years. The dependent variable or y-axis would be labeled "distance" and the unit would be in miles. It would be labeled this way because the distance that a monarch butterfly flies is dependent on the length of time.

Conduct a survey of individuals who are overweight and individuals who are not. Determine which group has the highest incidence of diabetes.

observational experiment

If being overweight helps cause diabetes, then individuals who are overweight will be more often diabetic than those who are not.

prediction

Submit the results and the conclusions to the scientific community.

report

Establish identical groups of laboratory rats. Raise one group of rats to be overweight and compare the incidence of diabetes (if any) with the incidence in the control group.

Laboratory experiment

Compile test results, create graphs, and draw conclusions from them.

asses results

Being overweight may help cause diabetes.

hypothesis

Why do overweight people get diabetes?

question

Diabetes is found in overweight people.

observation

Explain why science cannot prove anything but we still use scientific theories.

Science cannot prove anything-- it can only support or falsify. Although we cannot prove that gravity is a part of our natural environment, we know it is. This is a scientific theory. A scientific theory will have evidence. For gravity, we can toss a pen into the air over and over, and it will always land back in our hands. This is our evidence that gravity exists. In an experiment, we can test that if we throw something in the air, then it will always come back down. The results will always be the same-- the pen will come back down. However, we cannot call gravity an absolute truth. Absolute truth would require an infinite number of tests in every variation.

Explain sampling error and provide an example.

A sampling error is when there is a non-representative sample that skews data from the true results. An example of this would be if you are tossing a coin during an experiment. This experiment would be collecting data on whether a coin lands on heads or tails. The sampling error in this kind of experiment would be if the coin lands on all heads. To avoid this error, you would need a larger sampling size.

Which is not one of the four atoms that make up the bulk of living organisms?

Calcium

The bond in which bonded atoms share electrons is called a(n) ________.

covalent bond

Individual water molecules are held to one another by relatively weak ________ bonds.

hydrogen

Organic compounds are distinguished by molecules that contain ________ bonded to other elements.

carbon

What are the four classes of large organic molecules important to life on Earth?

Carbohydrates, proteins, lipids, and nucleic acids

What are the monomers of proteins?

Amino acids

What kind of bond joins amino acids together to form a protein?

Peptide bond

To a large extent, a protein's function is dependent upon its shape. What determines a protein's shape?

The sequence of amino acids

What might happen if a protein has a change in one amino acid?

The amino acid chain folds incorrectly. ,The protein can no longer function properly. ,The protein has a new shape.

Enzymes are a type of ________.

protein

What is the monomer of the DNA molecule?

Nucleotide

What is different from one DNA nucleotide to the next?

The base

Which enzyme is responsible for adding complementary DNA bases to an exposed DNA strand?

DNA polymerase

According to the base pairing rules of DNA, if the sequence of bases on one strand was AGGCTTA, what would be the sequence of bases on the complementary strand?
Correct!

TCCGAAT

If DNA directs the production of RNA, what does RNA make?

RNA makes proteins.

What does "transfer RNA" actually transfer?

Amino acids

How is translation initiated?

Two ribosomal subunits bind to the mRNA transcript.

In what way(s) can mRNAs be processed?

By splicing the exons (the coding regions) of the mRNAs in different ways ,By removing the introns (the noncoding regions) of the mRNAs ,By adding caps and tails to the ends of the mRNAs ,

Explain how one gene make different proteins?

In the cell, different combinations of these individual exons are “glued” or spliced together to generate a final expressed gene product; thus, a single gene can encode a set of distinct, but related protein isoforms, depending on the specific exons that are spliced.

In chemical bonding, when the bonded atoms share electrons, it is specifically called

a covalent bond

Fred Griffith discovered that when he injected mice with a mixture of dead pathogenic S cells and living harmless R cells of
Streptococcus pneumoniae

the mice died, and their bodies had living pathogenic S strain cells.

A specific stretch of DNA that programs the amino acid sequence of a polypeptide is a ______.

gene

The backbone of DNA consists of ______.

a repeating sugar-phosphate-sugar-phosphate pattern

In a DNA double helix, adenine pairs with ______ and guanine pairs with ______.

thymine . . . cytosine

After replication, ______.

each new DNA double helix consists of one old strand and one new strand

DNA polymerase assembles new strands

in a 5' to 3' direction only.

How does RNA differ from DNA?

RNA contains uracil; DNA contains thymine.

____ molecules carry protein-assembly instructions from the nucleus to the cytoplasm.

Messenger RNA

What type of chemical bond joins the bases of complementary DNA strands?

hydrogen

The region of DNA where RNA polymerase binds is ______.

promoter

Before leaving the nucleus and to become functional, the RNA molecule

acquires a poly-A tail.,is released from the DNA template. ,becomes capped. ,is stripped of its introns.

In transcription,

only a small section of DNA called a gene is used. ,a promoter sequence is needed. ,DNA produces messenger RNA. ,a specific enzyme called RNA polymerase is required.

The portion of the DNA molecule that is translated is composed of

exons.

Of all the different codons that exist, three of them

provide instructions such as STOP.

How many nucleotides make up a codon?

three

Which of the following carries amino acids to ribosomes, where amino acids are linked into the primary structure of a polypeptide?

tRNA

Which structure is involved in the initiation stage?

a specific tRNA ,an mRNA transcript ,a small ribosomal subunit ,a large ribosomal subunit

Which event occurs during the elongation stage?

Peptide bonds form, and anticodons bind to complementary codons.

During the termination stage

a STOP codon enters the ribosome.,release factors bind the ribosome. ,mRNA detaches from the ribosome and the polypeptide chain. , ribosomal subunits separate.

During replication, ______ are the enzymes responsible for joining the nucleotides of a new DNA strand together.

DNA polymerases

What is used to do translation?

ribosomes

Proteins are polymers constructed from ______ monomers.

amino acid

What kind of bond exists between two amino acids in a protein?

peptide

The linear sequence of amino acids in a polypeptide chain is referred to as its ______ structure.

primary

A single protein strand folded into a globular mass represents

tertiary structure.

The interaction of four polypeptide chains in a functional hemoglobin protein molecule is its ____ structure.

quaternary

Denaturation of proteins may result in all of the following EXCEPT

endangerment of a cell's life.

Nucleotides are the building blocks (monomers) for

nucleic acids

Which of the following is NOT found in every nucleic acid?

ribose

Enzymes are ______.

proteins

Which of the following statements is false?

Enzymes allow some reactions to occur that would never occur without them.

Enzyme activity may be affected by

temperature. ,
concentration ,
feedback inhibition. ,
pH.