Introduction to Biology
Characteristics of Life
K. Nifong, 2013
Biology
• Biology: the study of life
Characteristics of Living Things
There are 8 main characteristics of all living things.
What does it mean to be living?
http://news.discovery.com/videos/are-viruses-alive.htm
Organization
• Living things are organized in their structure.
• Cells  tissues  organs  organ systems
• Structure and Function
• What organ systems make up humans?
Cells
• Living things are made of cells!
• Unicellular – single-celled; less complex
• Multicellular – many cells; more complex and differentiated
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DNA
• Living things have a genetic code for their inherited traits.
Reproduction
• All living things create more individuals through reproduction.
• Asexual – single parent cell divides
• Budding, fission
• Ex. Bacteria
• Offspring are identical
• Sexual – 2 parent cells unite
• Ex. Animals, sperm and egg
• Offspring are unique
Metabolism
• Living things must obtain and use materials and energy.
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Must constantly carry out many chemical reactions to survive.
Nutrients
Energy from sun or energy from feeding on others
Ex. Digestion, Respiration
Stimulus and Response
• Living things respond to stimuli in
order to maintain HOMEOSTASIS!!!
• Stimulus – what happens
• Response – reaction to what happens
• Can be voluntary or involuntary
• Homeostasis – constant maintenance
of an organism’s internal conditions
• ex. pH, temperature
Growth and Development
• Living things grow and develop in their lifetime!
• Unicellular organisms increase size before dividing
• Ex. Child  Adult; Caterpillar  Butterfly
Adaptation
• Living things pass genetic traits from one generation to the next.
• Adaptation: genetic trait that makes an organism better suited for its
environment and survival
• Adaptations can lead to evolution of a species.
Characteristics of Life team activity
• Work together with your group to complete the following:
• 1. Write down an explanation for that characteristic in your own
words in your focus journal. Include examples and details.
• Extra Details textbook page 16-20
• 2. Prepare a short presentation to explain your characteristic to
the class, including examples and details about it. You may do a
short speech, quick song, poem, or act it out.
• Total Time: 10 minutes to plan, 1-2 minute presentations