IB 150 learning targets exam 1 Questions With Complete
Solutions
1A. Define and be able to write a hypothesis as a statement that
reflects a potential explanation for the research question. Correct
Answers Hypothesis: a supposition or proposed explanation
made on the basis of limited evidence as a starting point for
further investigation.
1C. Differentiate between independent and dependent variables,
and use them appropriately to set up predictions of concrete
results you would expect, if the hypothesis is correct. Correct
Answers Independent variable: a variable that is changed or
controlled in a scientific experiment to test the effects on the
dependent variable.
Dependent variable: a variable being tested and measured in a
scientific experiment
1F. Identify the roles and utility of control treatments,
replication of treatments, and sample size in any experiment.
Correct Answers Control treatments: baseline for measure,
identical to all the other items/subjects that you are examining
with the exception that it does not receive the treatment or
experimental manipulation
Replication of treatments: repetition of the set of all the
treatment combos to be compared in an experiment
Sample size: number of units in a population to be studied
2A. List the five characteristics all organisms on earth share.
Correct Answers 1. grow and reproduce (replicate)
, 2. react to environment
3. maintain highly ordered internal states via homeostasis
4. evolve
5. USE ENERGY TO DO WORK
2B. Explain why the first four are required for life. Correct
Answers 1. Organisms require energy to stay alive and
reproduce
2. All organisms are made of cells. The chemical reactions that
sustain life take place inside the cells.
3. Cells contain genetic information that encodes for an
organism to be alive.
4. Organisms also must respond to information from the
environment and adjust to maintain homeostasis
5. Cells must replicate during meiosis to ensure that all
organisms contain the correct number of chromosomes
2C. Understand how the ability to perform work is related to
being alive. Correct Answers It's necessary for our cells to
constantly do work in order for it to stay out of chemical
equilibrium--once the cell reaches chemical equilibrium with the
outside world, it's considered dead. Our body wants to be in
equilibirum; equilibrium = deaththat is why work is done--->to
keep our body out of equilibrium. Endergonic reactions are vital
to life: maintaining homeostasis
2D. Predict the direction of net flow of water across a cell
membrane due to osmosis given information about solute
concentrations on either side of the membrane. Explain what
happens to rates of movement of water molecules in both
directions across the membrane at equilibrium. Correct Answers
Solutions
1A. Define and be able to write a hypothesis as a statement that
reflects a potential explanation for the research question. Correct
Answers Hypothesis: a supposition or proposed explanation
made on the basis of limited evidence as a starting point for
further investigation.
1C. Differentiate between independent and dependent variables,
and use them appropriately to set up predictions of concrete
results you would expect, if the hypothesis is correct. Correct
Answers Independent variable: a variable that is changed or
controlled in a scientific experiment to test the effects on the
dependent variable.
Dependent variable: a variable being tested and measured in a
scientific experiment
1F. Identify the roles and utility of control treatments,
replication of treatments, and sample size in any experiment.
Correct Answers Control treatments: baseline for measure,
identical to all the other items/subjects that you are examining
with the exception that it does not receive the treatment or
experimental manipulation
Replication of treatments: repetition of the set of all the
treatment combos to be compared in an experiment
Sample size: number of units in a population to be studied
2A. List the five characteristics all organisms on earth share.
Correct Answers 1. grow and reproduce (replicate)
, 2. react to environment
3. maintain highly ordered internal states via homeostasis
4. evolve
5. USE ENERGY TO DO WORK
2B. Explain why the first four are required for life. Correct
Answers 1. Organisms require energy to stay alive and
reproduce
2. All organisms are made of cells. The chemical reactions that
sustain life take place inside the cells.
3. Cells contain genetic information that encodes for an
organism to be alive.
4. Organisms also must respond to information from the
environment and adjust to maintain homeostasis
5. Cells must replicate during meiosis to ensure that all
organisms contain the correct number of chromosomes
2C. Understand how the ability to perform work is related to
being alive. Correct Answers It's necessary for our cells to
constantly do work in order for it to stay out of chemical
equilibrium--once the cell reaches chemical equilibrium with the
outside world, it's considered dead. Our body wants to be in
equilibirum; equilibrium = deaththat is why work is done--->to
keep our body out of equilibrium. Endergonic reactions are vital
to life: maintaining homeostasis
2D. Predict the direction of net flow of water across a cell
membrane due to osmosis given information about solute
concentrations on either side of the membrane. Explain what
happens to rates of movement of water molecules in both
directions across the membrane at equilibrium. Correct Answers
