Chapter 1 homework questions key
1. What level of organization in the hierarchy for life are the following items at?
a. Kidney cells - cell
b. Carbon dioxide- molecule
c. A group of monkeys containing multiple species- community
d. Rhesus monkeys in a tree- population
e. Rainforest- ecosystem
2.
Explain what an emergent property is and give an example
Properties that were not present at the previous lower level and result
from the specific arrangement and interactions between components.
Example- engine, organ systems
3.
What are producers? What are consumers?
Producers produce organic compounds from inorganic compounds
Consumers obtain nutrients from other organisms
4.
How are the levels of life ordered in a hierarchy?
According to complexity
5.
Which one of the following sequences illustrates a hierarchy that increases in
complexity?
A) ecosystem, population, organ system, cell, community, molecule, organ, organism,
tissue
B) cell, molecule, organ system, organ, population, tissue, organism, ecosystem,
community
C) organism, organ system, tissue, population, organ, community, cell, ecosystem,
molecule
D) molecule, cell, tissue, organ, organ system, organism, population, community,
ecosystem
E) ecosystem, molecule, cell, tissue, organism, organ system, organ, community
6.
Which of the following is/are properties of life?
A) a complex organization
B) the ability to take in energy and use it
C) the ability to respond to stimuli from the environment
D) the ability to reproduce
E) All of the choices are correct.
7.
Consider the following statement: "If all vertebrates have backbones, and turtles
are vertebrates, then turtles have backbones." This statement is an example of
A) a hypothesis.
B) discovery science logic.
C) rationalization.
D) deductive reasoning.
E) inductive reasoning.
8.
To be scientifically valid, a hypothesis must be
A) phrased as a question.
B) based on faith.
C) testable.
D) falsifiable.
E) testable and falsifiable.
9.
Briefly explain the role of a control in an experiment
Ensure that the result is the product of a single variable that is being manipulated
10.
You are conducting an experiment teaching mice to run through a maze. To do
this, two groups of mice are used: one group receives a food reward upon successful
completion of the maze and the other group does not. You conduct one test run per day
for a period of 6 days and record the time required to complete the maze. At the end of
the 6 days you have the following data:
With food
reward
Average time to
complete maze
(min)
25
23
16
11
5
7
Day
1
2
3
4
5
6
Without food
reward
Average time to
complete maze
(min)
25
23
19
15
12
11
Day
1
2
3
4
5
6
A. State a hypothesis you think this experiment tested
B. Which group is the control group in this experiment?
B. Identify the independent and dependent variables
D. Graph the results of the experiment
If positive reinforcement via a food reward encourages learning, then mice who
receive a food reward will learn a maze more quickly than those who do not.
Control group is the group that does not receive a food reward.
Independent variable is the day.
The dependent variable is the time taken to complete the maze.
Time taken to complete maze vs Days of training
30
Time (min)
25
With food reward
20
15
Without food reward
10
5
0
0
2
4
6
8
Day
11. Identify if each of the following are observational or experimental science
A. Jane Goodall observing lowland gorilla behavior
Observational
B. A drug study where one groups receives blood pressure medication and
another a placebo
Experimental
C. An anthropologist living among and studying indigenous peoples of South
America
Observational
D. Drinking several flavors of tea to see which helps you study longer
Experimental
12. Name two things that are and two things that are not biology
Are Biology;
Ethology
Evolutionary Biology
Physiology
Genetics
Molecular Biology
Ecology
Are not Biology
Chemistry
Engineering
13. What criteria must sometime meet to be considered “science”
Observable, testable, measurable
14. Which statement best distinguishes hypotheses from theories in science?
A. Theories are hypotheses that have been proved
B. Hypotheses are tentative guesses: theories are correct answers to questions
about nature
C. Hypotheses are usually narrow in scope, theories have broad explanatory
power
D. Hypotheses are different terms for essentially the same thing in science
E. Theories are proved true in all cases, hypotheses are usually falsified by tests
15. Explain what biology is and what it does and does not encompass. Give two examples
of subjects it encompasses.
Biology must be testable and observable
Not- religion, theology
Does- ethology, ecology
16. Rewrite the following statements into a testable hypothesis
A. Temperature causes leaf color to change
B. Students who read the chapter before class perform better in class
C. Chocolate causes pimples
D. If a person is in shape, they will have a better pulse than someone who is not
E. If you are a smoker, does your heart rate take longer to return to resting rate
F. A pea plant will grow at a constant rate if watered daily
A. If temperature causes leaf color to change, then leaves exposed to different
temperatures will turn different colors.
B. If reading material before class influences student success, then students who
read the chapter before class will do better than those who don’t.
C. If chocolate causes pimples then people who do not eat chocolate will have fewer
pimples than those who do eat chocolate
D. If a persons physical condition affects pulse rate then someone who has a better
physical condition (is in shape) will have a better pulse than someone who is not in
shape
E. If smoking affects the time it takes the heart to return to resting state after
exercise, then the heart of people who smoke will take longer to return to resting
rate than those who do not smoke.
F. If water effects plant growth then pea plants that are watered daily will grow at a
constant rate.
Chapter 2 questions
1. The four most common elements in living organisms are
A) C, H, O, Fe.
B) C, H, O, Na.
C) C, H, O, N.
D) C, N, O, Na.
E) Fe, N, O, Ca.
2. What is a trace element and identify which of the following is not a trace element in
the human body
A trace element is…..
An element that is present in minute amounts, yet is critical to life
A) fluorine
B) nitrogen
C) zinc
D) manganese
E) iodine
3. Define a neutron, proton and electron. Include their charges and location in an atom
Neutron- found in the nucleus, is a particle with a neutral charge
Proton- Found in the nucleus, is a particle with a positive charge
Electron- found around the nucleus in electron shells, is a particle with a negative
charge
4. What is a valence shell?
The outermost shell of electrons that interacts with other atoms
5. Identify the number of protons, neutrons and electrons for the following, assuming the
atoms have neutral charges:
Ru
Li
Atomic number 44
Atomic number 3
Atomic weight 101.07
Atomic weight 6.9
Protons 44
Protons 3
Neutrons 57
Neutrons 4
Electrons 44
Electrons 3
S
Atomic number 16
Atomic weight 32.06
Protons
16
Ga
Atomic number 31
Atomic weight 69.72
Protons 31
Neutrons 16
Electrons 16
Neutrons 39
Electrons 31
Ti
Atomic number 22
Atomic weight 47.9
Protons 22
Neutrons 26
Electrons 22
6. What happens if you add or remove a proton from an atom?
It becomes another atoms
7. What is the difference between an isotope and an ion?
Isotope is a variation in the number of neutrons. An ion is a variation in the number
of electrons
8. A hydrogen bond is a type of ____________ bond
Covalent (polar covalent)
9. A compound…..
A) is a pure element.
B) is less common than a pure element.
C) contains two or more elements in a fixed ratio.
D) is exemplified by sodium.
E) is a solution.
10. A(n) __________ forms when two atoms share electrons.
A) ion
B) element
C) covalent bond
D) ionic bond
E) hydrogen bond
11. A water molecule (H-O-H) is held together by
A) an ionic bond.
B) a single covalent bond.
C) a polar covalent bond.
D) hydrogen bonds.
12. The hydrogen atoms of a water molecule are bonded to the oxygen atom by
__________ bonds, whereas neighboring water molecules are held together by
__________ bonds.
A) hydrogen . . . ionic
B) hydrogen . . . polar covalent
C) polar covalent . . . hydrogen
D) ionic . . . covalent
E) polar covalent . . . ionic
13. The ability of water molecules to form hydrogen bonds with other water molecules
is critical to
A) evaporative cooling of skin surfaces.
B) the movement of water from the roots of a tree to its leaves.
C) the milder temperatures of coastal regions compared to inland areas.
D) the ability of certain insects to walk on the surface of water.
E) all of these factors.
14. You've made a hot drink by dissolving a teaspoon of instant coffee and a teaspoon of
sugar in a cup of hot water.
What kind of solution is this?
Identify the solute and solvent
Aqueous
Solute is the coffee and sugar
Solvent is the water
15. How is radiation helpful and harmful? Give an example of each
Helpful in medical fields, research etc. Example is irradiation of food products for
safety.
Harmful in high quantities. Example is nuclear bombs
16. What type of covalent bond is formed when electrons are equally shared?
Non-polar
17. Describe how water helps regulate coastal temperatures. What unique feature of water
makes this possible?
H bonds absorb a great deal of energy before breaking, thus, a lot of energy is
required before an increase in temp occurs
18. Sketch a Helium atom, including sub-atomic particles. Label the particles. Atomic #
is 2
Electron
Proton
Neutron
19. A solution of pH 6 contains ____ than the same of amount of solution at pH 8
2 times more H+
4 times more H+
100 times more H+
4 times less H+
100 times less H+
20. Magnesium Oxide (MgO) is a moisture absorbent used by libraries for preserving
books. Oxygen has a greater electronegativity than magnesium. The electron structures
appear as follows:
Which atom will gain and which atom will loose electrons? What will the charge be on
each atom?
Mg will loose 2 electrons, O will gain 2 electrons. The charge of Mg will
be +2 and the charge on O will be -2