Biology 105Biology 105

Asking About Life

CHAPTER 1CHAPTER 1

The Unity and Diversity of Life

Chapter 1Chapter 1

Bacteria: Enough to Give You an Ulcer Key Concepts How Do Biologists Ask Questions?

Do Scientists Use the Scientific Method?

Do Scientists Use the Scientific Method?

scientific method

How Do Observations Lead to Models?

How Do Observations Lead to Models?

observations, models

What Is a Hypothesis?What Is a Hypothesis?

hypothesis

Where do hypotheses come from?

Where do hypotheses come from?

How do scientists decide if a hypothesis is correct?

What Makes a Good Experiment?

What Makes a Good Experiment?

control groups

How Do Scientists Design Experiments?

How Do Scientists Design Experiments?

Reductionism

What Is a Testable Hypothesis?

What Is a Testable Hypothesis?

testable

How Do Scientists Evaluate Experiments That Give

Varying Results?

How Do Scientists Evaluate Experiments That Give

Varying Results?Statistics

What Is Theory?What Is Theory?

Give Examples.

Biologists Ask Many Kinds of Questions?

Biologists Ask Many Kinds of Questions?

WHAT DO WE KNOW ABOUT LIFE?

WHAT DO WE KNOW ABOUT LIFE?

How Are Organisms Different from One Another?

How Are Organisms Different from One Another?

Eubacteria and Archaea - Bacteria Eukarya

• Four Kingdoms– PROTISTA– FUNGI– PLANTAE– ANIMALIA

HOMEOSTASIS AND NEGATIVE FEEDBACKHOMEOSTASIS AND

NEGATIVE FEEDBACK

BOX 1-2

How Are Organisms Alike?How Are Organisms Alike?

ORGANIZED PARTS PERFORM CHEMICAL REACTIONS OBTAIN ENERGY FROM THEIR

SURROUNDINGS CHANGE RESPOND TO THEIR ENVIRONMENT REPRODUCE COMMON EVOLUTIONARY HISTORY

How Can We Tell If Something Is Alive?How Can We Tell If Something Is Alive?

Living organisms share many individual traits with nonliving things.

Only living organisms share a common ancestry.

Organisms Are Made of CellsOrganisms Are Made of Cells

EUKARYOTIC TRUE CELLS HAVE A NUCLEUS ORGANELLES

• mitochondria

PROKARYOTIC ARCHAIC CELLS NO NUCLEUS NO MEMBRANE

ORGANELLES EX. - BACTERIA

How do living organisms replace worn-out parts?How do living organisms replace worn-out parts?

A multicellular organism can lose and replace individual cells.

How much do organisms resemble one another

chemically?

How much do organisms resemble one another

chemically?SUGARS

AMINO ACIDS

LIPIDS

NUCLEOTIDES

Why Do Children Look Like Their Parents?

Why Do Children Look Like Their Parents?

Genes ensure continuity from generation to generation.

What are genes made of?What are genes made of?

DNA

NUCLEOTIDES

What creates variations from one generation to the next?

What creates variations from one generation to the next?

Mutations

What determines the characteristics of an

individual?

What determines the characteristics of an

individual?PHENOTYPE

How Do Organisms Become Different from One Another?How Do Organisms Become Different from One Another?

Common ancestry

Every species has a unique set of adaptations to the environment.

How Do We Know That the Diversity of Life Resulted from

Evolution?

How Do We Know That the Diversity of Life Resulted from

Evolution?The fossil record.

CHARLES DARWINCHARLES DARWIN

Evolution through natural selection H. M. S. Beagle He read several books. Collections from his grandfather Fossil record common traits in animals embryology selective breeding

The Origin of Species The Origin of Species

Natural selection over a very long period of time.

How are traits passed from one generation to the next?How are traits passed from one generation to the next?

Gregor Mendel formulated the laws of heredity.