Do Now

• What is the scientific method?

(use your notes)

Unit 1 The Nature of Life

Ch. 1 The Science of Biology

What Science Is and Is Not

• The goal of science is to investigate & understand the natural world, to explain events in the natural world, & to use those explanations to make useful predictions

What is Science?

• Science – an organized way of using evidence to learn about the natural world

Thinking Like a Scientist

• Observation – process of gathering info about events or processes

• Data – info gathered from observations• Inference – an interpretation

based on prior knowledge or experience

Explaining & Interpreting Evidence

• Hypotheses – a proposed scientific explanation for a set of observations (if…then…)

Designing an Experiment

• 1. Ask a question• 2. Form a hypothesis• 3. Set up a controlled experiment

– Controlled experiment – where only 1 variable is tested at a time, everything else is kept constant

Designing an Experiment

• 4. Record & analyze results• 5. Draw a conclusion

Building Science SkillsRecall a common superstition, such as the one that proposes that a black cat crossing your path brings bad luck or your own.• How would you use an experiment to verify

or disprove this superstition. • Using the steps on the next slide. • Work in groups of three and design an

experiment using the scientific method• Write steps in your NUA notebook and

leave room to write a response to each step

Scientific Method Steps• Ask a question• Form a hypothesis• Set up a controlled

experiment• Record and analyze data• Draw a Conclusion

1-1 Section AssessmentWrite in your NUA notebook • Get your textbook on the book shelve• Go to page 7 in your textbook• Answer questions 1, 3, 4 and 5

Homework (definitions of terms)

Vocabulary: Spontaneous Generation, Controlled Experiment, Manipulated Variable, Responding Variable & Theory

Do Now

List the 5 steps of the scientific method

How a Theory Develops

• As evidence from many investigations builds up, a hypothesis may become so well supported that scientists consider it a theory

Characteristics of Living Things

• Biology – the study of life• Living things share

The following 8 characteristics:• 1. Made up of cells• 2. Reproduce• 3. Based on a universal genetic code• 4. Grow & Develop

Characteristics of Living Things

• 5. Obtain & use materials & energy• 6. Respond to their environment• 7. Maintain a stable internal environment• 8. As a group, living things change over

time

Characteristics of Living ThingsLab (write in your NUA notebook)

Work in groups of 2 and examine the 2 pictures on the next slide.

Car Cat

Compare the two, noting similarities and differences. Collaborate using the characteristics of living things to write a paragraph explaining what makes the picture a living thing and the other not.

Pictures

Made Up of Cells

• Cell – a collection of living matter enclosed by a barrier that separates the cell from its surroundings– They can grow, respond to surroundings, &

reproduce

Reproduction

• Sexual reproduction – 2 parents produce offspring

• Asexual reproduction – 1 parent produces offspring

There are two organisms shown in the photo, which organism represents sexual reproduction? Why does the other organism not represent sexual reproduction?

Based on a Genetic Code

• DNA (deoxyribonucleic acid) – molecule that carries directions for inheritance, for every organism on Earth

Growth & Development

• All living things grow during at least part of their lives

Need for Materials & Energy

• Metabolism – all the chemical reactions that take place within an organism, to carry out life processes, which requires energy

Response to the Environment

• Stimulus – a signal that an organism responds to– Ex.) when there is enough water, & the ground

is warm enough, a plant seed responds by germinating

Maintaining Internal Balance

• Homeostasis – maintaining a stable internal environment, such as temperature & water content

Evolution

• As a group, any given kind of organism can evolve, or change over time

Branches of Biology

• Some of the levels that life can be studied include molecules, cells, organisms, populations of a single kind of organism, communities of different organisms in an area, & the biosphere

• At all of these levels, smaller living systems are found within larger systems

Complete flow chart of the Level of Organization (Page 21 textbook)

Start with the broadest level on top and work you way down to the smallest level.

Fill in __________ All ecosytemsEcosystem________ Fill in

Fill in___________ Population in a defined area

Population______ Fill in

Fill in_________ Individual living things

Groups of cells Fill in

Fill In______ Smallest functional unit of life

Molecule_ Fill In

1-2 Section AssessmentWrite in your NUA notebook • Get your textbook on the book shelve• Go to page 15 in your textbook• Answer questions 1, 2, 3 and 4

Homework (definitions of terms)

Vocabulary: biology, cell, sexual reproduction,

asexual reproduction, metabolism, stimulus, homeostasis and evolution.

Do Now

What is the difference between sexual reproduction and asexual reproduction?

A Common Measurement System

• Most scientists use the metric system when collecting data & performing experiments

• Metric system – International System of Units, or SI

Microscopes

• Microscopes – devices that produce magnified images of structures that are too small to see with the naked eye

Light Microscopes

• Compound Light Microscope – produce a magnified image by focusing visible light rays

Electron Microscopes

• Electron microscopes – produce magnified images by focusing beams of electrons

Electron Microscopes

• The best electron microscopes can produce images almost 1000 times more detailed than light microscopes can

**Remember B.U.B.

• Objects, when viewed under a microscope, appear: Bigger, Upside down, & Backwards