exploring and classifying life chapter 1. what is science? section 1

Exploring and Classifying Life

Chapter 1

What is Science?

Section 1

What is Science?

• Science is an organized way of studying things and finding answers to questions

• Series of steps to solve problems scientific method

• BrainPop• Safety Rap

http://glencoe.mcgraw-hill.com/sites/dl/free/0078617022/164155/00044686.html

http://www.teachertube.com/members/viewVideo.php?video_id=194405

M&M Lab

• You will be organizing and counting M&M candies to find out which color M&M is the most plentiful in each bag.

Question

• Which color of M&M is most plentiful?

Hypothesis

• If I count each color of M&M in a bag then _________ will be the most plentiful because _______________________________________________________.

Procedure

1. Do NOT eat anything in lab.2. Open a bag of M&Ms. 3. Count the numbers of each color.4. Record in chart.

DataColor Number Average

Group 1 Group 2 Group 3 Group 4 Group 5 Group 6 Group 7 Total

Red

Green

Orange

Yellow

Blue

Brown

• Graph Number of M&M v. Colors of M&M in a bar graph

• Label the x-axis as Colors of M&Ms horizontal axis

• Label the y-axis as Numbers of M&Ms vertical axis

• Make your graph as large as possible & colorful

• Glue or staple onto your lab paper

Conclusion• What did your hypothesis

say?• Was your hypothesis

correct? wrong?• Include your observations

and data• Give explanations.• Why would this information

be important or useful?

Next Step????• Talk with your lab

partners and come up with 2 questions about M&Ms that could be answered by doing a lab activity

Vocabulary

1. Hypothesis an educated guess or possible outcome to a problem

2. Procedure set of directions or steps to follow

3. Data Info gathered during an investigation

4. Graph picture of your data

5. Conclusion An answer to your question; was your hypothesis correct?

6. Variable things that are changed in an experiment

7. Control Things that are NOT changed in an experiment

Theory or Law?

• Scientific Law – a RULE that describes a pattern in nature– Does not try to explain why

• Scientific Theory - Attempt to explain a pattern observed repeatedly in the natural world– Can Δ w/ new data

Safety

• Follow all safety rules during an experiment

• Must make an 80% on lab safety quiz

11Section CheckSection Check

Question 1

This diagram shows a way to use scientific methods to solve a problem. According to the diagram, if a hypothesis is not supported by data then you should _______.


A. change the data so that they do support the hypothesis B. find a different problem to solveC. propose a scientific theoryD. revise the hypothesis and perform new experiments


Answer

The correct answer is D. Scientific methods are an organized way to solve a problem in science. This series of procedures involves forming a hypothesis that can be tested.


Question 2

What is the definition of a control in a scientific experiment?

Answer

A control is the standard to which the outcome of a test will be compared. Controls help you determine how to interpret your data.


Question 3

A statement about how things work in nature that seems to be true all the time is a _______.

A. conclusion B. hypothesisC. lawD. variable


Answer

The correct answer is C. Although laws can be modified as more information becomes known, they are less likely to change than theories.

Living Things

Section 2

What are living things like?

• Any living thing organism• All organisms share similar traits

1. Living things are organized

• Cell smallest unit of an organism that can carry on all the functions of life– Orderly structure – Contains hereditary material

2. Living things respond

• Stimulus anything that causes a Δ• Response reaction to a stimulus

Homeostasis

Stimulus Response

Your body temperature rises

because of exercise

3. Living things use Energy

• All energy ultimately comes from the Sun

Some organisms eat plants for energy

Some organisms make their own food from the Sun’s energy

Heterotrophs Autotrophs

4. Living things grow, develop, and die

• Development Δ that take place during the life of an organism

• Lifespan length of time an organism is expected to live

5. Living things reproduce

• Must replace individuals that die

List the characteristics of living things discussed in this video

clipStar the ones that are different than what we have discussed.

What do Living things need?

• Place to live• Raw materials

– Water– Oxygen– Food

• Different requirements for different organisms

Homework• Find 2 pictures of living things and 2

pictures of non-living things.• Either out of a magazine, real photos or

you can even draw them, glue or tape them into your notebook.

• Under each, list the characteristics the thing does or does not have that makes it alive or non-living.

• Bring them to class and be prepared to share with the class whether they are living things or non-living things and why.


Question 1

What is the smallest unit in a cat that carries on the functions of life?

AnswerThe cell is the smallest unit. All organisms are composed of cells. Cells take in materials from their surroundings and use them in complex ways.


Question 2

Pulling your hand back when you accidentally touch a hot pan on the stove is an example of what characteristic of living things?

A. growth and development B. organizationC. reproductionD. response to stimuli


Answer

The correct answer is D. The hot pan is an example of a stimulus. Living things can respond to both external and internal stimuli.


Question 3

Give an example of two raw materials that you need to survive.

Answer

Some possible answers include: water, food, and oxygen. Some bacteria and plants can make food from raw materials in their surroundings.

Where does life come from?

Section 3

Two ideas

Spontaneous generation Biogenesis

Sources of Life

Living things come from non-living things

Living things come only from other living things

Timeline Foldable

• Information on page 20 in textbook• Glue last page of foldable into NB

1668• Francesco Redi– Decaying meat in

jars & covered some

– Maggots appeared only on uncovered meat

– Conclusion: maggots hatched from fly eggs & not from the meat

1745• John Needham– Heated broth in

flasks– Became cloudy w/

microorganisms– Conclusion: they

developed spontaneously from the broth

– (WRONG!)

1768• Spallanzani– Heated broth in

sealed flasks– Only opened ones

became cloudy

1859• Louis Pasteur– Boiled broth in

open S-necked flasks

– Only became cloudy when tilted & exposed to dust in the S-neck

– Conclusion: no such thing as spontaneous generation

1924• Oparin Hypothesis– Earth’s early atmosphere

contained no oxygen, but did have ammonia, hydrogen, methane, & water vapor

– Chemical reactions triggered by• E from Sun• Lightning• Earth’s heat

– New molecules washed into Earth’s oceans primordial soup

1953• Miller and Urey– Sent electric

currents through gasses

– Cooled & condensed into liquid that contained amino acids (found in present-day cells)


This diagram shows an experiment Louis Pasteur conducted with boiled broth and S-necked flasks. Why did microbes only grow in the bottom flask?

Question 1


Microbes from the air settled out at the bottom of the S-neck and only entered the broth when it was tilted so that the broth touched this area. This experiment by Pasteur helped disprove the theory of spontaneous generation.

Answer


Which one of the following examples supports the theory of biogenesis?

Question 2

A. kittens are produced from cats B. milk is produced by cowsC. rain is produced by rain cloudsD. stimuli produce responses


The correct answer is A. The theory of biogenesis states that living things come only from other living things.

Answer


What did Alexander Oparin suggest about Earth’s early atmosphere?

Question 3


He suggested that it contained no oxygen but was made up of the gases ammonia, hydrogen, methane, and water vapor. He hypothesized that these gases could have combined to produce compounds found in living things.

Answer

How are living things classified?

Section 4

Classification• Placing similar

things together into groups

• Aristotle – Plant or Animal– Broke these down

into smaller groups

• Linnaeus– Classification based on

similar structures

• Modern scientists– Use similarities in internal

structure as well– Chromosome #– Fossil record– Very early stages of

development

Six Kingdoms

Scientific Names

• Common names can be confusing

• Binomial Nomenclature 2-word name (1st – genus, 2nd – species)

Uses of Scientific Names1. Avoid mistakes2. Organisms w/

similar evolutionary history are grouped together

3. Give descriptive information

4. Info can be organized easily & efficiently

Dichotomous Keys

• Detailed list of characteristics• Includes scientific names• Series of steps that leads you to the

correct identification• Alien Identification activity

– Cut out Alien Sheet and glue in NB– Make a list 1-20– Use dichotomous key to label aliens


Question 1

Over 2,000 years ago, Aristotle developed a system to classify all organisms _______.

A. as either plant or animal.B. based on fossils. C. into six different kingdoms.D. using binomial nomenclature.


Answer

The correct answer is A. Aristotle broke these two groups into smaller groups. Two of his smaller groups of animals would have been animals with hair and those with no hair.


Question 2

What word is used to describe the evolutionary history of an organism?

AnswerThe word is phylogeny. Phylogeny explains how an organism has changed over time and is the basis for the modern classification of many organisms.


Question 3

Acer rubrum is the scientific name for a red maple tree. This name is an example of _______.

A. a dichotomous key B. a hypothesisC. binomial nomenclatureD. spontaneous generation


Answer

The correct answer is C. Binomial nomenclature is the system used by modern scientists to name organisms. The first part of the scientific name identifies the genus of the organism.

Chapter ReviewChapter Review

Question 1Why has the hypothesis in this example been used to propose a theory?


Answer

In the example, several different experiments have all supported the hypothesis. In science, if the results of experimentation always support a particular hypothesis, the hypothesis can then be called a theory. A theory usually explains many hypotheses.


Question 2

Which one of the following is an example of using field work to collect data about where robins build their nests?

A. doing an internet search on robinsB. finding a book on robins in the library C. watching robins in a laboratoryD. watching robins in a park


Answer

The correct answer is D. Fieldwork includes observations or experiments that are done outside the laboratory.


Question 3

Why is reproduction an important characteristic of living things?


Answer

Without reproduction, living things could not replace individuals that die and would soon no longer exist. Reproduction can take many different forms, including production of spores, laying eggs, or giving birth to live young.


Question 4

What is the estimated age of Earth?

A. 4600 years oldB. 4.6 million years oldC. 4.6 billion years oldD. 4.6 trillion years old


Answer

The correct answer is C. Rocks found in Australia more than 3.5 billion years old are one piece of data that supports this estimation.


Question 5This is the classification of the bottle-nosed dolphin. Which one of the following organisms from the order Cetacea is most closely related to the bottle-nosed dolphin?


A. Bow-head whale from the Family BalaenideaB. Ganges River dolphin from the Family Platanistidae

C. Killer whale from the Family Delphinidae

D. Right whale from the Family Balaenidea


The correct answer is C. The bottle-nose dolphin and the killer whale are more closely related than the others because they are classified in the same family of Delphinidae.

Answer

Standardized Test PracticeStandardized Test Practice

Question 1Which measurement should be made using the SI unit of meters instead of the units shown in the table?

Measurements to make SI unit to use

Volume of water in jar milliliters

Height of a bookshelf grams

Mass of a sofa kilograms

Distance to the moon kilometers


A. distance to the moonB. height of a bookshelfC. mass of a sofaD. volume of water in a jar

Measurements to make SI unit to use

Volume of water in jar milliliters

Height of a bookshelf grams

Mass of a sofa kilograms

Distance to the moon kilometers


Answer

The correct answer is B. Height is a measurement of length and can be measured in meters. The SI unit of a gram is a measurement of mass.


Question 2

Why might you find these symbols in your text book?


A. to alert you to situations that require special attention B. to help you study for test on each chapterC. to show you where to find certain information in the textD. to warn you to turn the page quickly


Answer

The correct answer is A. These are safety symbols that are used throughout your text.


Question 3

Like all living things, you require energy to survive. What is the source of the energy used by your body?

A. carbon dioxide B. the SunC. food that you eatD. oxygen


Answer

The correct answer is C. You get food by eating plants or other organisms that ate plants. Plants make their own food through photosynthesis. Therefore, you use the Sun’s energy indirectly.


Question 4Stanley Miller and Harold Urey conducted this experiment to find out if gases in Earth’s early atmosphere could have produced _______.


A. bacteria from viruses B. chemicals found in living things C. electricityD. mice from grain


The correct answer is B. They hypothesized that lightning in Earth’s early atmosphere could have caused the gases to combine to produce these chemicals. They passed an electrical current through those gases to simulate what might have happened.

Answer


Dichotomous keys are arranged in steps with two _______.

Question 5

A. descriptive statements at each stepB. kingdoms at each stepC. pictures at each stepD. scientific names at each step


The correct answer is A. If you learn how to use a dichotomous key, you can identify and name species.

Answer

exploring and classifying life chapter 1. what is science? section 1

Documents

scientific law

scientific experiment

scientific methods

scientific theoryd

variable things

bag of mms

experimentcontrol things

lab paperconclusionwhat