Characteristics of Living Things Section 1 Bellringer What are four living and nonliving things that you interact with every day? How do you know whether

Characteristics of Living ThingsSection 1

Bellringer

What are four living and nonliving things that you interact with every day? How do you know whether each is living or nonliving? Do you know what the word inanimate means? If so, write out a definition. Does nonliving mean the same thing as dead? Explain your answer.

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It’s Alive!! Or Is It?Chapter 2

Section 1: Characteristics of Living Things

Section 2: The Necessities of Life


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Living Things Have Cells

• What Is a Cell? A cell is a membrane-covered structure that contains all of the materials necessary for life.

• How Many Cells? Some organisms are made up of only one cell and some are made up of trillions of cells.


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Living Things Sense and Respond to Change

• Homeostasis The maintenance of a stable internal environment is called homeostasis.

• Responding to External Change Organisms must respond to change in the external environment in order to maintain their homeostasis.


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Living Things Reproduce

• Having Offspring Organisms make other organisms similar to themselves. They do so in one of two ways: by sexual reproduction or by asexual reproduction.


Living Things Have DNA

• DNA in Cells The cells of all living things contain the molecule deoxyribonucleic acid, or DNA.

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Living Things Use Energy

• Energetic Organisms Organisms use energy to carry out the activities of life.


Living Things Grow and Develop

• Growing Up All living things, whether they are made of one cell or many cells, grow during periods of their lives.

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Discussion:

What are four living and nonliving things that you interact with every day? How do you know whether each is living or nonliving? Do you know what the word inanimate means? If so, write out a definition. Does nonliving mean the same thing as dead? Explain your answer.


The Necessities of Life Section 2

Objectives

• Explain why organisms need food, water, air, and living space.

• Describe the chemical building blocks of cells.


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The Necessities of LifeSection 2

Water


• Thirsty Cells Your cells and the cells of almost all living organisms are approximately 70% water.

Air

• Oxygen Air is a mixture of several different gases, including oxygen and carbon dioxide. Most living things use oxygen in the chemical process that releases energy from food.

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A Place to Live


• Home Sweet Home All organisms need a place to live that contains all of the things they need to survive.

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Food


• Making Food Some organisms, such as plants, are called producers. Producers can make their own food.

• Taking Food Other organisms are called consumers because they must eat (consume) other organisms to get food.

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Putting It All Together


• Using Nutrients Some organisms make their own food. Some organisms get food from eating other organisms. But all organisms need to break down that food in order to use the nutrients in it.

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Proteins


• Making Proteins Organisms break down the proteins in food to supply their cells with amino acids. These amino acids are then linked together to form new proteins.

• Proteins in Action Proteins have many different functions. Other proteins are very small and help cells do their jobs. Other proteins, called enzymes, start or speed up chemical reactions in cells.

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Carbohydrates


• Simple Carbohydrates Simple carbohydrates are made up of one sugar molecule or a few sugar molecules linked together.

• Complex Carbohydrates Complex carbohydrates are made of hundreds of sugar molecules linked together.

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Lipids


• Phospholipids Phospholipids are the molecules that form much of the cell membrane. A phospholipid’s membrane is shown on the next slide.

• Fats and Oils Fats and oils are lipids that store energy.

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Phospholipid Molecules and Cell MembraneSection 2



Nucleic Acids


• What Are Nucleic Acids? Nucleic acids are large molecules made up of molecules called nucleotides.

• Blueprints of Life Nucleic acids are sometimes called the blueprints of life because they have all the information needed for a cell to make proteins.

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It’s Alive!! Or Is It?Chapter 2

Concept Map


Use the following terms to complete the concept map on the next slide: DNA, sugars, energy, enzymes, living cells proteins, starches, carbohydrates.

Concept MapChapter 2


Concept MapChapter 2


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Characteristics of Living Things Section 1 Bellringer What are four living and nonliving things that you interact with every day? How do you know whether