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UNIT 1: INTRODUCING BIOLOGY

Chapter 1: Biology in the 21st Century

UNIT 1: INTRODUCING BIOLOGY Chapter 1: Biology in the 21st Century

I. The Study of Life (1.1)

A. Earth is home to an incredible diversity of

life

1. The biosphere includes all living things and all

the places they are found.

2. Every part of the biosphere is connected with

every other part.

3. The biosphere includes many environments

a. Land environments

Tidepool Estuary

b. Saltwater and freshwater environments

c. Portions of the atmosphere

4. Biodiversity is the variety of life

a. Generally increases

from the poles to the

equator

b. Greater in areas with

consistently warm

temperatures.

5. A species is one particular type of living thing.

a. Members of a species can interbreed and

reproduce.

b. About 2 million

different living species

identified.

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B. All organisms share certain characteristics

1. Biology is the scientific study of all forms

of life.

2. An organism is any individual living thing.

a. All are made of one or more cells

b. All need energy for metabolism

c. All respond to their environment

d. All have DNA that they pass on to offspring.

II. Unifying Themes of Biology (1.2)

A. All levels of life have systems of related parts

1. A system is an organized group of interacting

parts.

a. A cell is a system of chemicals and

processes.

b. A body system includes organs that interact

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c. An ecosystem includes living and nonliving

things that interact.

2. Biologists study many different systems

B. Structure and function are related in biology

1. Structure determines function

a. Proteins with different structures

perform different functions.

b. Heart muscle cells have a different

structure and function than

stomach muscle cells.

c. Different species have different

anatomical structures with different

functions.

C. Organisms must maintain homeostasis to

survive in diverse environments.

1. Homeostasis is the maintenance of

constant internal conditions.

a. Homeostasis is usually maintained through

negative feedback

b. Negative feedback systems return a condition

to its normal (set) point.

2. Behaviors and adaptations can help maintain

homeostasis.

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D. Evolution explains the unity and diversity of life

1. Evolution is the change in living things

over time.

a. The genetic makeup of a population

of a species changes

b. Evolution can occur through natural

selection of adaptations.

c. Adaptations are beneficial inherited

traits that are passed to future

generations.

2. Evolution accounts for both the diversity and

unity of life.

III. Scientific Thinking and Processes (1.3)

A. Like all science, biology is a process of

inquiry

1. Scientists make careful and systematic

observations.

2. Scientists record observations as data

3. Scientists form a hypothesis as a possible

answer to a question

4. Scientists test their hypotheses and analyze their

data.

Francesco Redi (1600’s)-

designed one of the first

controlled experiments.

Redi designed experiment

to determine what caused

appearance of maggots on

meat

B. Biologists use experiments to test hypotheses

1. Observational studies allow scientists to

describe a phenomenon

2. Experiments allow scientists to determine

what causes a phenomenon

Pasteur’s experiment showed that boiled broth would remain

free of microorganisms even if air was allowed in, as long as

dust and other particles were kept out

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a. Independent variables are manipulated

b. Dependent variables are observed and

measured.

c. Constants are conditions that are kept the same

C. A theory explains a wide range of observations

1. Theories explain a wide range of

observations and experimental results.

2. A theory is supported by a wide range of

scientific evidence.

3. Theories can

change based on

evidence

IV. Imaging technologies provide new views of life

(1.4)

A. A microscope provides enlarged image of

an object.

stoma

1. Light microscope

2. Scanning electron microscopes (SEM)

stoma

3. Transmission electron microscope (TEM)

stoma

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B. Imaging technology is used in medicine

1. X-ray images

2. Magnetic resonance imaging (MR)

3. Functional MRI (fMRI)

C. Complex systems are modeled on computers

1. Computer models are used to study

systems that cannot be studied directly

a. Heart attacks

Normal heartbeat Heart attack

b. Effect of medicines on the human body

c. Movement of water molecules into and out of a

cell

d. Spread of a diseases through a population

Computer model of

flu pandemic

2. Computer models are used when experiments

are not safe, ethical, or practical

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D. The tools of molecular genetics five rise to new

biological studies.

1. A gene is segment of DNA that stores

genetic information

2. Through our understanding DNA, we can study

genetics on a molecular level

a. molecular genetics

b. Genomics

V. Your health and the health of the environment

depend on your knowledge of biology (1.5)

A. Knowledge of biology helps you

understand your health

1. Food allergies

2. Potential effects of

obesity

3.cancer

4. Effects of alcohol,

tobacco, and other drugs.

B. Knowledge of biology can help you understand

environmental issues.

1. Interactions in ecosystems

2. Pollution

3. Biodiversity

C. Biotechnology offers great promise but also

raises many issues.

1. Biotechnology is the use and application

of living things and biological processes.

a. DNA testing in medicine and

forensics

b. Transgenic (genetically modified)

crops

c. Transgenic bacteria

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Tracy (1990-1997) was a transgenic ewe that had

been genetically modified by the Roslin Institute,

near Edinburgh, Scotland, so that her milk

produced a human protein called alpha antitrypsin,

a potential treatment for the disease cystic fibrosis.

2. Questions are raised about the use of

biotechnology

a. Safety of genetically modified crops

b. Spread of undesirable genes

c. Decrease in biodiversity

d. Ethical considerations

D. Biology presents many unanswered

questions

1. Over the past 50 years, biological

knowledge has greatly increased.

2. There are still many questions to answer in

biology.

3. Advances in technology may help answer

questions.

a. How are memories

stored in the brain?

b. How do viruses mutate?

Tools and Procedures

A. A common Measurement System

1. Scientist use the Metric System (SI

system)- a decimal system based on certain

standards and scaled on multiples of 10

2. System is easy to use because based on

units of 10

B. Analyzing Biological Data– many times use

data tables and graphs to more easily detect

patterns of change

C. Interpreting the Evidence

a. Observation alone has little meaning in

science

b. Observation usually followed by

inference (a logical interpretation based on

prior knowledge and experience)

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Chapter 1

The Nature of Life

The work of scientists begins with

a. testing a hypothesis.

b. careful observations.

c. creating experiments.

d. drawing conclusions.

The work of scientists begins with

a. testing a hypothesis.

b. careful observations.

c. creating experiments.

d. drawing conclusions.

Science differs from other disciplines, such as

history and the arts, because science relies on

a. facts.

b. testing explanations.

c. observations.

d. theories.

Science differs from other disciplines, such as

history and the arts, because science relies on

a. facts.

b. testing explanations.

c. observations.

d. theories.

Information gathered from observing a plant grow 3

cm over a two-week period results in

a. inferences.

b. variables.

c. hypotheses.

d. data.

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Information gathered from observing a plant grow 3

cm over a two-week period results in

a. inferences.

b. variables.

c. hypotheses.

d. data.

You state that the presence of water could

accelerate the growth of bread mold. This is a(an)

a. conclusion.

b. hypothesis.

c. experiment.

d. analysis.

You state that the presence of water could

accelerate the growth of bread mold. This is a(an)

a. conclusion.

b. hypothesis.

c. experiment.

d. analysis.

Hypotheses may arise from

a. prior knowledge.

b. logical inferences.

c. imaginative guesses.

d. all of the above

Hypotheses may arise from

a. prior knowledge.

b. logical inferences.

c. imaginative guesses.

d. all of the above

Which of the following is a valid hypothesis for why a

plant appears to be dying?

a. The plant is not being watered enough.

b. The plant is being watered too much.

c. The plant is receiving too much sunlight.

d. all of the above

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Which of the following is a valid hypothesis for why a

plant appears to be dying?

a. The plant is not being watered enough.

b. The plant is being watered too much.

c. The plant is receiving too much sunlight.

d. all of the above

In science, a hypothesis is useful only if

a. it is proven correct.

b. it can be proven incorrect.

c. it can be tested.

d. the explanation is already known.

In science, a hypothesis is useful only if

a. it is proven correct.

b. it can be proven incorrect.

c. it can be tested.

d. the explanation is already known.

Which of the following is NOT a part of doing

science?

a. experimenting

b. observing

c. generalizing

d. hypothesizing

Which of the following is NOT a part of doing

science?

a. experimenting

b. observing

c. generalizing

d. hypothesizing

Which of the following variables present in Redi’s

experiment on spontaneous generation is NOT a

controlled variable?

a. gauze covering that keeps flies away from

meat

b. types of jars used

c. types of meat used

d. temperature at which the jars were stored

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Which of the following variables present in Redi’s

experiment on spontaneous generation is NOT a

controlled variable?

a. gauze covering that keeps flies away from

meat

b. types of jars used

c. types of meat used

d. temperature at which the jars were stored

When enough experimental data supports a

hypothesis, the hypothesis becomes a(an)

a. fact.

b. theory.

c. inference.

d. conclusion.

When enough experimental data supports a

hypothesis, the hypothesis becomes a(an)

a. fact.

b. theory.

c. inference.

d. conclusion.

A theory

a. is always true.

b. is the opening statement of an experiment.

c. may be revised or replaced.

d. is a problem to be solved.

A theory

a. is always true.

b. is the opening statement of an experiment.

c. may be revised or replaced.

d. is a problem to be solved.

A well-tested explanation that unifies a broad

range of observations is a(an)

a. hypothesis.

b. inference.

c. theory.

d. controlled experiment.

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A well-tested explanation that unifies a broad

range of observations is a(an)

a. hypothesis.

b. inference.

c. theory.

d. controlled experiment.

Biology is the study of

a. the land, water, and air on Earth.

b. the living world.

c. animals and plants only.

d. the environment.

Biology is the study of

a. the land, water, and air on Earth.

b. the living world.

c. animals and plants only.

d. the environment.

Which of the following is NOT a characteristic of

all living things?

a. growth and development

b. ability to move

c. response to the environment

d. ability to reproduce

Which of the following is NOT a characteristic of

all living things?

a. growth and development

b. ability to move

c. response to the environment

d. ability to reproduce

Which of the following characteristics of living

things best explains why birds fly south for the

winter?

a. Living things respond to their environment.

b. Living things maintain internal balance.

c. Living things are made up of units called

cells.

d. Living things are based on a universal

genetic code.

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Which of the following characteristics of living

things best explains why birds fly south for the

winter?

a. Living things respond to their

environment.

b. Living things maintain internal balance.

c. Living things are made up of units called

cells.

d. Living things are based on a universal

genetic code.

The process by which organisms keep their

internal conditions relatively stable is called

a. homeostasis.

b. evolution.

c. metabolism.

d. photosynthesis.

The process by which organisms keep their

internal conditions relatively stable is called

a. homeostasis.

b. evolution.

c. metabolism.

d. photosynthesis.

What is the term for a group of organisms of one

type living in the same place?

a. biosphere

b. ecosystem

c. population

d. environment

What is the term for a group of organisms of one

type living in the same place?

a. biosphere

b. ecosystem

c. population

d. environment

Which is NOT a unit of measurement in the metric

system?

a. meter

b. inch

c. liter

d. gram

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Which is NOT a unit of measurement in the metric

system?

a. meter

b. inch

c. liter

d. gram

To observe a small living organism, a scientist

might use a(an)

a. electronic balance.

b. TEM.

c. compound light microscope.

d. electron microscope.

To observe a small living organism, a scientist

might use a(an)

a. electronic balance.

b. TEM.

c. compound light microscope.

d. electron microscope.

Which of the following is the best reason for using

a scanning electron microscope?

a. ability to magnify objects that are larger than

0.2 micrometers

b. ability to observe live organisms

c. ability to see three-dimensional images of

the surfaces of objects

d. ability to see movement within living cells

Which of the following is the best reason for using

a scanning electron microscope?

a. ability to magnify objects that are larger than

0.2 micrometers

b. ability to observe live organisms

c. ability to see three-dimensional images

of the surfaces of objects

d. ability to see movement within living cells

An instrument that allows light to pass through the

specimen and uses two lenses to form an image

is a(an)

a. compound light microscope.

b. electron microscope.

c. TEM.

d. SEM.

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An instrument that allows light to pass through the

specimen and uses two lenses to form an image

is a(an)

a. compound light microscope.

b. electron microscope.

c. TEM.

d. SEM.

Safety procedures are important when working

a. in a laboratory.

b. in the field.

c. with animals.

d. all of the above

Safety procedures are important when working

a. in a laboratory.

b. in the field.

c. with animals.

d. all of the above

Which of the following is NOT considered a safety

procedure?

a. Read all the steps in your activity before

doing it.

b. If in doubt about any part of an activity, trust

your instincts.

c. Follow your teacher’s instructions.

d. Follow the textbook direction exactly.

Which of the following is NOT considered a safety

procedure?

a. Read all the steps in your activity before

doing it.

b. If in doubt about any part of an activity,

trust your instincts.

c. Follow your teacher’s instructions.

d. Follow the textbook direction exactly.