1

Virtual Lab - Dependent and Independent Variables Name:

Biology Date: Period:

Introduction: In this lab, you will use a simulation to further your understanding of independent and dependent

variables. You will be studying the level of European Corn Borer infestation in various environments.

Open the Simulator at: http://www.mhhe.com/biosci/genbio/virtual_labs/BL_01/BL_01.html

(alternately, use Google to search for "mhhe virtual labs"

1. Read the introduction. You will change the independent variable, and then you will observe and measure the

dependent variable. In this experiment, what will be the independent and dependent variable?

2. Explain what is meant by the term "yield" with regard to this experiment. What factors can affect a corn's

yield?

3. Open the Greenhouse Handbook and scan to find information about Bt corn. What makes Bt corn different

from the other variety? What is the purpose of creating Bt corn?

4. What are some questions or worries that people might have about transgenic plants?

2

5. Read the instructions for setting up your chambers. Here you can make some decisions about what level of

ECB infestation you will start with. Change one variable at a time. Record your measurements in the data

table.

Analysis:

Corn Variety Level of ECB

infestation Pot 1 Yield Pot 2 Yield Pot 3 Yield Average

6. Describe the effects of the ECB infestations you used. Were all corn varieties equally effective at

controlling the ECB? How do you know?

7. Did the level of ECB infestation change your results?

8. What is the purpose of taking an average?

3

Identify Controls and Variables

Read the description of each experiment. Identify the parts of the experiment listed below.

Experiment I: A student wants to know if her hosta plants (normally grown in shaded areas) will be able to

grow under full sunlight. She plants 10 hostas in a shaded area of her yard. She plants 10 more in an area of

her yard that receives full sun exposure. She waters them three times a week for 6 weeks. After six weeks, she

measures the heights of the hostas.

A. Hypothesis: If the (independent variable – describe how it will be changed), then the (dependent variable – describe the effect). Be specific.

B. Experimental Group:

C. Independent (manipulated) Variable:

D. Dependent (responding) Variable:

E. Constants:

Experiment II: A student wants to know what effect temperature will have on the germination rate of radish

seeds. To test this, she obtains 3 petri dishes and 60 radish seeds. She places 20 seeds in the first petri dish and

stores it at room temperature. She places another 20 seeds in the second dish and places it in the freezer. She

places 20 seeds in the third petri dish and places the dish in an incubator. Over the next two weeks, she waters

the dishes daily and records the number of seeds germinated. At the end of the experiment she calculates the

germination rate for the seeds at each temperature.

A. Hypothesis:

B. Experimental Group:

C. Control Group:

D. Independent (manipulated) Variable:

E. Dependent (responding) Variable:

Experiment III: In 1887 a strange nerve disease attacked the people in the Dutch East Indies. The disease was

beriberi. Symptoms of the disease included weakness and loss of appetite, victims often died of heart failure.

Scientists thought the disease might be caused by bacteria. They injected chickens with bacteria from the blood

of patients with beriberi. The injected chickens became sick. However, so did a group of chickens that were not

injected with bacteria. One of the scientists, Dr. Eijkman, noticed something. Before the experiment, all the

chickens had eaten whole-grain rice, but during the experiment, the chickens were fed polished rice. Dr.

Eijkman researched this interesting case. He found that polished rice lacked thiamine, a vitamin necessary for

good health.

A. Hypothesis:

B. Experimental Group:

C. Control Group:

D. Independent (manipulated) Variable:

E. Dependent (responding) Variable:

4

Experiment IV: A botanist thinks that mustard plants will grow faster in red light compared to sunlight. The

following table shows his experimental design.

Experimental Group Control Group

Type of Light Red Sunlight

Type of plant Mustard Garden Pea

Temperature 20ºC 30ºC

Amount of Water 5 ml /day 10 ml/day

The botanist measures the height of each plant daily and uses this information to calculate a growth rate after a

two-week period. He concludes that his hypothesis is incorrect because the plant in sunlight showed a faster

growth rate than the plant in red light.

1. How many manipulated variables were there in this experiment? How many should it have?

2. Help the botanist fix his experiment by completing the table below.

Experimental Group Control Group

Type of Light Type of Plant Temperature Amount of Water

3. What is the manipulated variable in the experiment now?

4. List the constants in the experiment.

Experiment V: Jordan is doing a science fair project on the effects of music on the growth of

tomatoes. He has two tomato plants, Plant A and Plant B, which he grows in the same window and

they are given the same amount of water. Plant A is exposed to classical music using headphones

attached to the soil. Throughout the one month growth period, Jordan counts the number of tomatoes

produced by each plant. The results are in the data table below:

Plant A Plant B

Week 1 2 5

Week 2 6 11

Week 3 12 19

Week 4 18 29

Week 5 26 40

Week 6 35 55

A. Hypothesis:

B. Experimental Group:

C. Control Group:

5

D. Independent (manipulated) Variable:

E. Dependent (responding) Variable:

F. What type of graph should be used to show the results of this experiment and explain why?

G. What should Jordan’s conclusion be? Write this in a complete sentence and be specific.

H. Jordan needs to repeat the experiment, but his teacher says that he needs to improve his design. In his

second experiment, what are at least two things that he should do differently?

Experiment VI: Tina asks the question “Does caffeine increase the heart rate of an earthworm?”

In Test 1, she measures the heart rate by looking at the earthworm under a microscopes, the

earthworm has a heart rate of 50 bpm (beats per minute). In Test 2, she places a few drops of

caffeine on the earthworm’s skin and measures the rate again. In this test, the heart rate is 68 bpm.

A. Hypothesis:

B. Control Group:

C. Independent (manipulated) Variable:

D. Dependent (responding) Variable:

E. What is an experimental constant? __________________________________________________________

F. Tina needs to improve her experimental design. In her second experiment, what are at least two things that

he should do differently?

How Penicillin Was Discovered

In 1928, Sir Alexander Fleming was studying Staphylococcus bacteria growing in culture dishes. He noticed

that a mold called Penicillium was also growing in some of the dishes. A clear area existed around the mold

because all the bacteria that had grown in this area had died. In the culture dishes without the mold, no clear

areas were present. Fleming hypothesized that the mold must be producing a chemical that killed the bacteria.

Explain how Fleming could test his hypothesis ______________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

6

How Penicillin was Discovered Antibiotics are chemical compounds that selectively kill microorganisms, many of which cause diseases.

Although we may take antibiotics for granted today, penicillin was discovered only about 85 years ago. The

subsequent development of a wide array of other antibiotics for treating many common diseases has contributed

greatly to the substantial increase in life expectancy over the past 50 years.

In 1928, Alexander Fleming, a young microbiologist at the University of London, was working with a common

bacterium, Staphylococcus, which is commonly found on the skin or in the nose of healthy individuals. But

staph infections can turn deadly if the bacteria invade deeper into your body entering your bloodstream, joints,

bones, lungs or heart. For laboratory study, bacteria are commonly grown on the surface of a nutrient-

containing gel in small, flat culture dishes.

One day Fleming noticed that one of his cultures was contaminated by a bluish-green mold similar to the mold

found on spoiled bread or fruit. Such accidents are rather common, and most laboratory workers would have

simply thrown the cultures away. Fleming noticed, however, that the bacteria were growing everywhere on the

gel except near the contaminating mold (Figure 1a). He thought that the mold must be producing a substance

that either killed the bacteria or prevented their growth.

To test his hypothesis, Fleming used Staphylococcus bacteria as well as other strains of bacteria. He set up

several bacterial cultures in the regular nutrient gel (Group A). He also set up the same bacterial cultures in the

nutrient gel that contained the Penicillium mold (Group B). All of the bacteria in Group A grew all over the

cultures in the nutrient gel. All of the bacteria in Group B did not grow around the Penicillium mold.

Because the mold was a member of the Penicillium family (named for their pencil-shaped branches under the

microscope) (Figure 1b), Fleming called the active ingredient penicillin.

Figure 1

a) bacterial growth in nutrient gel

b) Penicillium mold is growing in a culture dish; the photo shows its effect on bacterial growth.

c) In this photomicrograph of Penicillium, its rod- and pencil-shaped branches are visible. The name comes

from the Latin penicillus, meaning “paintbrush.”

7

1) What was Fleming’s hypothesis?

2) What type of data was collected in experiment - Qualitative or Quantitative? Why?

3) Could it be both qualitative and quantitative? How?

4) Does this indicate that Penicillin will inhibit growth or kill ALL bacteria? Explain.

5) Why is it important for Fleming to report and share his results?

8

Graphing Practice

Step 1: Choosing the correct type of graph When to Use a. . . .

Bar Graph

Bar graphs are used to compare things between different

groups or to track changes over time. However, when trying to

measure change over time, bar graphs are best when the

changes are larger.

Line graph

Line graphs are used to track changes over short and long

periods of time. When smaller changes exist, line graphs are

better to use than bar graphs. Line graphs can also be used to

compare changes over the same period of time for more than

one group. Pie Chart

Pie charts are best to use when you are trying to compare parts

of a whole. They do not show changes over time.

Step 2: Setting up your axes Always put the independent variable along the X-axis and the dependent on the Y-axis.

Make sure that your scale is consistent (For example, 1 block = 5 days) and can be determined very easily.

Work with multiples of 1, 2, 5.

Never put any “breaks” (those squiggly things you do in math class) in the axis.

Step 3: Plot your data Start out but just putting data points on your graph.

Connect the points with a line if you’re

making a line graph.

Draw your bars if you are making a bar

graph.

Step 4: Label your graph. Title: This should be a statement

explaining what your graph is about

(usually more than just a couple of words,

not just X vs. Y)

X and Y Axes should also include labels

and units

Make a key/legend if there is more than

one data set on a single graph.

9

10

11

1. What type of graph is this?

2. Which insect has the fewest wing vibrations per second?

3. A cicada vibrates its wings about 300 times per second. Which insect is a cicada’s vibration rate most similar to?

1. What type of graph is this?

2. What happens to the number of predators when the number of prey increase?

3. Why do you think this happens?

4. What happens to the number of predators when the number of prey decrease?

5. Why do you think this happens?

12

13

14

Questions:

1. Would a line graph or a bar graph be better for showing the number of birds of each color in a population?

Why?

2. How could you plot more than one responding variable on a line graph?

3. Where do you place the manipulated variable on a graph?

4. Which type of graph would you use to show comparisons? Explain.

5. Why is it important to have all parts of a graph clearly labeled?

15

A wild-life researcher was collecting data to determine what animal has the strongest bite. Data table 1 shows

the data that the researcher collected in the field.

1. Did the researcher choose the correct type of graph for this data? Explain.

2. Identify the dependent and the independent variable in this study. Are the dependent and the independent

variables set up on the correct axes?

3. Fill in the missing labels on the X and Y axes.

4. “Bite Force” is not a very good title for this graph? What would be a better title for this graph?

0

200

400

600

800

1000

1200

Snapping TurtlesHyena Lion Domestic DogWild Dog Humans Shark

Bite Force

Data Table 1: Bite Force Data

Animal Bite Force

(pounds per square inch)

Snapping Turtle 1004

Hyena 1000

Lion 691

Domestic Dog 328

Wild Dog 317

Humans 127

Shark 669

16

The researcher believes that an animal’s bite force corresponds with the animal’s mass. In other words, the

heavier the animal, the stronger the bite force.

5. Make a graph (on graph paper) for the data in table 2.

Data Table 2: Animal Weights

Animal Average Weight (in pounds)

Male Female

Snapping Turtle 180 150

Hyena 149 153

Lion 399 278

Domestic Dog 130 95

Wild Dog 60 44

Humans (U.S.) 195 170

Shark 795 1050

A zoo is trying a new experimental growth hormone to determine if it will cause their lion cubs to grow any

faster. 4 Lion cubs are given the growth hormone and 4 lion cubs are not given the growth hormone.

6. Make a graph (on graph paper) for the data in table 3.

Data Table 3: Lion Growth Rate

Day 0 10 20 30 40 50 60 70

Average Weight

(Pounds)

No growth Hormones

12.2 26.5 37.1 45.1 52.2 58.7 64.1 69.6

Average Weight

(Pounds)

With Growth Hormones

11.5 24.8 36.2 46.8 59.7 75.0 94.9 117.3

The zoo wants to determine if the new growth hormone will also work on the hyena pups. The zoo has 12

hyena pups, 6 are given the growth hormone and 6 are not given any growth hormone. The hyena pups are

more aggressive then the lion cubs and could not be weighed at regular intervals.

7. Add the hyena data in table 4 to the lion graph. (Do not make a whole new graph)

Data Table 4: Hyena Growth Rate

Day 0 15 22 27 45 52 64 70

Average Weight

(Pounds)

No growth Hormones

7.8 13.2 18.2 20.0 28.6 29.4 32.5 34.1

Average Weight

(Pounds)

With Growth Hormones

8.0 12.6 18.9 21.1 29.1 30.1 32.3 33.8

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Practice Identifying Parts of the Scientific Method

Directions: The following are experimental scenarios. Read the experiments and then identify the components

of the scientific method by completing the graphic organizer provided.

Experimental Scenario #1

A student investigated whether ants dig more tunnels in the light or in the dark. She thought that ants used the

filtered light that penetrated the upper layers of earth and would dig more tunnels during the daytime. Ten ant

colonies were set up in commercial ant farms with the same number and type of ants per ant farm. The same

amount of food was given to each colony, and the colonies were in the same temperature. Five of the colonies

were exposed to normal room light and five were covered with black construction paper so they did not receive

light. Every other day for three weeks the length of the tunnels was measured in millimeter using a string and a

ruler. Averages for the light and dark groups for each measured were then computed. The averages are listed in

the following chart.

Length of Tunnels (mm) Constructed by Ants in Different Light Conditions

Day Light Dark

1 5 7

3 10 15

5 20 25

7 26 32

9 32 47

11 50 62

13 61 93

15 66 110

17 90 115

19 95 120

21 103 136

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Experimental Scenario #2

A student investigated the effect of aged-grass compost (fertilizer made from decaying plant material) on the

growth of bean plants. She thought that the compost would provide extra nutrients and make plants grow faster.

Thirty bean seeds were divided into three groups and planted in different flats (boxes). All seeds germinated after

12 days and were allowed to grow for five days. The flats were ach given the same amount of water and the same

amount of light. Flat A was then fertilized with 3-month old compost; Flat B was given 6-month old compost;

and Flat C was given no compost. At the end of 14 days the height of each plant was measured in centimeters.

Final Heights (in cm) of Bean Plants

Plant 3-month old

Compost

6-month old

Compost No Compost

1 7.6 10.1 6.5

2 5.4 9.5 7.2

3 8.2 12.1 8.4

4 9.3 13.0 11.0

5 8.2 8.5 6.9

6 6.9 13.1 6.8

7 7.3 12.4 6.3

8 9.4 11.6 10.7

9 10.2 14.8 9.9

10 12.0 10.8 10.6

AVERAGE:

19

Analysis of Experimental Scenario 1

- Graphic Organizer -

Problem/Observation:

Question:

Hypothesis:

Experiment:

Procedures

Independent Variable

Dependent Variable

Controls

Control Group

Experimental Group(s)

20

Results/Data (Graph):

Conclusion:

21

Analysis of Experimental Scenario 2

- Graphic Organizer -

Problem/Observation:

Question:

Hypothesis:

Experiment:

Procedures

Independent Variable

Dependent Variable

Controls

Control Group

Experimental Group(s)

22

Results/Data (Graph):

Conclusion:

23

Metric Prefixes

1. Identify each unit by what it measures. Choose your answer from the following: length, mass,

temperature, or volume.

a) centimeter ________________

b) C ________________

c) deciliter ________________

d) mm ________________

e) cL ________________

f) hectogram ________________

g) L ________________

h) Kelvin ________________

i) g ________________

j) kilometer ________________

2. Give the abbreviation for each of the following units.

a) kilometer ________________

b) hectogram ________________

c) megagram ________________

d) deciliter ________________

3. Give the name of the following abbreviations

a) mm ______________________

b) cL ______________________

c) dag ______________________

d) m ______________________

4. Place the value in the blank that matches each unit.

a) 1 km = _____________ m

b) 1 m = _____________ dm

c) 1 g = _____________ mg

d) 1hL = _____________ L

e) 1 L = _____________ cL

f) 1 dag = _____________ g

5. Convert the following metric measurements to the units indicated.

a) 120 mm = _________ cm

b) 43 cm = _________ m

c) 280 cm = _________ hm

d) 3 m = _________ dm

e) 5.2 mm = _________ cm

f) 25 dag = _________ kg

g) 22.4 mL = _________ ML

h) 4 nm = _________ m

i) 4 cm = _________ mm

j) 80 cm = _________ km

k) 80 dm = _________ mm

l) 43 m = _________ cm

m) 3 µL = _________ mL

n) 2 µm = _________ nm

o) 3.1 dm = _________ km

p) 3.5 hL = _________ cL

q) 3 nm = _________ mm

r) 3 hm = _________ dm

s) 1.23 cm = _________ m

t) 100000 m = ________ µm

u) 5000 µg = _________ kg

v) 100 mm = _________ dm

w) 1000 g = _________ kg

x) 2.3 kg = _________ ng

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Section 1.3 Characteristics of Life

LESSON OBJECTIVES

List the characteristics of living things.

Identify the central themes of biology.

Explain how life can be studied at different levels.

Discuss the importance of a universal system of measurement.

LESSON SUMMARY

Characteristics of Living Things - Biology is the study of life. Living things share these characteristics: They

are made of cells and have a universal genetic code; they obtain and use materials and energy to grow and

develop; they reproduce; they respond to signals in their environment (stimuli) and maintain a stable internal

environment; they change over time.

Big Ideas in Biology - The study of biology revolves around several interlocking big ideas:

Cellular basis of life. Living things are made of cells.

Information and heredity. Living things are based on a universal genetic code written in a molecule

called DNA.

Matter and energy. Life requires matter that provides raw material, nutrients, and energy. The

combination of chemical reactions through which an organism builds up or breaks down materials is

called metabolism.

Growth, development, and reproduction. All living things reproduce. In sexual reproduction, cells from

two parents unite to form the first cell of a new organism. In asexual reproduction, a single organism

produces offspring identical to itself. Organisms grow and develop as they mature.

Homeostasis. Living things maintain a relatively stable internal environment.

Evolution. Taken as a group, living things evolve, linked to a common origin.

Structure and function. Each major group of organisms has evolved structures that make particular

functions possible.

Unity and diversity of life. All living things are fundamentally similar at the molecular level.

Interdependence in nature. All forms of life on Earth are connected into a biosphere—a living planet.

Science as a way of knowing. Science is not a list of facts but “a way of knowing.”

Fields of Biology - Biology includes many overlapping fields that use different tools to study life. These

include biotechnology, global ecology, and molecular biology.

Performing Biological Investigations - Most scientists use the metric system as a way to share quantitative

data. They are trained in safe laboratory procedures. To remain safe when you are doing investigations, the most

important rule is to follow your teacher’s instructions.

25

Characteristics of Living Things - Use pages 18-20 in your textbook.

1. Complete the graphic organizer to show the characteristics living things share.

2. The genetic molecule common to all living things is .

3. The internal process of enables living things to survive changing

conditions.

4. Living things are capable of responding to different types of .

5. Living things have a long history of change.

6. The continuation of life depends of both and

reproduction.

7. The combination of chemical reactions that make up an organism’s help to

organize raw materials into living matter.

8. Growth occurs by cell and .

are made up of basic

units called

________________

are based on a

universal genetic

________________

grow, develop, and

________________

respond to their

___________________

as they mature

maintain a stable

internal

________________

obtain and use

materials and

________________

Living things

26

Big Ideas in Biology – Read pages 20-21 to complete the following table on the Big Ideas in Biology. The first

row is filled in for you.

Big Idea Description

Cellular basis of life Living things are made of cells.

Information and heredity

Life requires matter that provides raw materials, nutrients, and

energy.

Growth, development, and reproduction

Living things maintain a relatively stable internal environment.

Evolution

Each major group of organisms has evolved structures that

make particular functions possible.

All living things are fundamentally similar at the molecular

level.

All forms of life on Earth are connected into a biosphere—a

living planet.

Science as a way of knowing

27

Intro to Biology Test Review

1. 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…

A. an increase in matter, but no increase in the number of icicles.

B. an interaction between the icicle and the environment.

C. no way for the icicle to move away from heat.

D. no metabolic activity present.

2. A company that manufactures a popular multivitamin wanted to determine whether their multivitamin had

any side effects. For its initial study, the company chose 2000 individuals to take one of their multivitamin

tablets per day for one year. Scientists from the company surveyed the participants to determine whether

they had experienced any side effects. The greatest problem with this procedure is that

A. only one brand of vitamin was tested.

B. the study lasted only one year.

C. the sample size was not large enough.

D. no control group was used.

An experiment was designed to test whether students could squeeze a clothespin more times in one minute after

resting or after exercise.

3. The dependent variable for this experiment is the

A. time the student was squeezing the clothespin.

B. number of times the student was able to squeeze the clothespin.

C. strength of the student.

D. length of the clothespin.

4. The experimental result could be made more valid by

A. increasing the time.

B. using a plastic clothespin.

C. using safety precautions.

D. setting a specific type of exercise.

5. The leaves of a plant are dotted with opening known as stomata. When open, stomata allow the plant to

exchange gases and allow moisture to evaporate, helping to draw water from the roots up into the plant.

These activities help the plant to

A. produce light energy.

B. maintain homeostasis.

C. undergo cellular division.

D. synthesize minerals.

6. Why is a mushroom considered a heterotroph?

A. It manufactures its own food.

B. It divides by mitosis.

C. It transforms light energy into chemical energy.

D. It obtains nutrients from its environment.

28

The data table shows an effect of secondhand smoke on the birth weight of babies born to husbands and wives

living together during pregnancy.

Effect of Secondhand Smoke on Birth Weight

Wife: Nonsmoker

Husband: Nonsmoker

Wife: Nonsmoker

Husband: Smoker

Number of Couples 837 529

Average Weight of Baby at Birth 3.2 kg 2.9 kg

7. Based on these data, a reasonable conclusion that can be drawn about secondhand smoke during pregnancy

is that secondhand smoke

A. is unable to pass from the mother to the fetus.

B. slows the growth of the fetus.

C. causes mutations in cells of the ovaries.

D. blocks the receptors on antibody cells.

8. The ability of the human body to keep blood sugar levels within a fairly narrow range, despite the intake of

meals high in carbohydrates, is an example of

A. metabolism.

B. asexual reproduction.

C. an adaption.

D. homeostasis.

9. Which statement best describes a hypothesis?

A. A hypothesis is the process of making careful observations.

B. The conclusion drawn from the results of an experiment is part of a hypothesis.

C. A hypothesis serves as a basis for determining what data to collect when designing an experiment.

D. The facts collected from an experiment are written in the form of a hypothesis.

A scientist conducted an experiment to test the hypothesis that maple seeds exposed to acid rain will take longer

to germinate than seeds exposed to normal rain, which has a pH of 5.6. The scientist set up four groups, each

containing 200 maple seeds. The water used for each group had a different pH value: 5.6, 4.0, 3.0, and 2.0. All

other conditions were kept the same. After ten days, the number of seeds that had germinated in each group

was counted.

10. Identify the control group:

11. Identify the experimental group:

12. Identify the independent variable:

13. Identify the dependent variable:

29

Chapter Vocabulary Review

Complete each statement by writing the correct word.

14. The act of noticing and describing events or processes in a careful, orderly way is called

___________________________.

15. The information gathered during an experiment is called __________________________.

16. A(n) ___________________________ is a logical interpretation based on what scientists already know.

17. A(n) ___________________________ is a scientific explanation for a set of observations that can be tested

in ways that support or reject it.

18. A(n) ___________________________ is a well-tested explanation that unifies a broad range of

observations and hypotheses.

19. In ___________________________ reproduction, the new organism has a single parent.

20. A(n) ___________________________ is a signal to which an organism responds.

21. ___________________________ is an organized way of gathering and analyzing evidence about the natural

world.

Write the letter of the definition that best matches each term on the line provided.

Term

______22. biology

______23. homeostasis

______24. metabolism

______25. DNA

______26. control group

______27. independent variable

______28. dependent variable

______29. biosphere

Definition

A. in an experiment, the group exposed to the same

conditions as the experimental group except for

one independent variable

B. the study of life

C. living things maintaining a relatively stable

internal environment

D. a molecule containing the universal genetic

code

E. a living planet

F. the combination of chemical reactions through

which an organism builds up or breaks down

materials

G. in an experiment, the variable that is

manipulated

H. in an experiment, the responding variable

30

30. All of the features are true of science except

A. deals with the natural world

B. collects and organizes information

C. explores the supernatural

D. proposes explanations based on evidence

31. All of the following are characteristics of all living things except the ability to

A. grow and develop.

B. maintain a stable internal environment.

C. change over time.

D. reproduce asexually.

32. All of the following are big ideas in biology except living things are

A. unable to adapt to their surroundings.

B. based on an universal genetic code.

C. made up of cells.

D. diverse.

33. In an experiment, the variable that is deliberately changed is the

A. inferred variable.

B. independent variable.

C. controlled variable.

D. dependent variable.

34. When working in a lab you should always

A. follow safe practices.

B. work with a partner.

C. use a microscope.

D. design your own experiment

35. Look at the images below. Each one is related to a characteristic of life. Some images may be related to

more than one characteristic of life. See if you can match at least one characteristic of life to each image:

A______________________________ B. ______________________________

C______________________________ D. ______________________________

Metric Review Examples:

1) 1 km = _______________ m

2) 0.45 L = _______________ mL

3) 5000 µg = _______________ mg

4) 130 m = _______________ km

5) 2500 mL = _______________ L

6) 0.017g = _______________ mg

7) 1 km = _______________ Mm

8) 0.45 L = _______________ µL

9) 5000 mg = _______________ kg

10) 130 m = _______________ nm

11) 2500 mL = _______________ nL

12) 17 g = _______________ Mg