Introduction to Biology and Life Science Mrs. Margreiter

What is Biology?  Bio  Life  ……ology  The study of  So Biology is  The science that uses scientific method to study living things.

Why is Biology Important?  Helps us to understand and care for our bodies.  Helps us understand our environment.  Helps us understand the resources we consume.  Helps us understand potential threats in our environment.

What are Living Things?  It is difficult to describe living things.  No single characteristic is enough to describe a living thing.  Some nonliving things share the traits of living things.  Living describes things that are both alive or have ever been alive.

  Icicle  Cell  River  Seed  Cloud  Clock  Coral  Fire  Bubbles  Chick  Cars  Jellyfish Is it a Living Thing?

What are Living Things?  Most living things share the following characteristics:  Living things are made up of units called cells.  Living things reproduce.  Living things are based on a universal genetic code.  Living things grow and develop.  Living things obtain and use materials and energy.  Living things respond to their environment.  Living things maintain a stable internal environment.  As a group, Living things change over time.

Living things are made up of units called cells.  A cell is the smallest unit of an organism that can be considered alive.  To see most cells you need a microscope.  Living things may be  Unicellular- they are made up of a single cell. (bacteria)  Multicellular- composed of many cells. (humans)

Living things reproduce.  All living things have the ability produce new living things.  Most plants and animals engage in sexual reproduction to reproduce.  Many single celled organisms and some plants reproduce using Asexual reproduction.  Sexual Reproduction- Cells from two different parents unite to form the first cells of the new organism.  Asexual Reproduction- A single parent produces offspring that are identical to the parent.

Living things are based on a universal genetic code.  The Genetic code is DNA.  DNA stores complex information that is needed to live, grow and reproduce.

Living things grow and develop.  Every living thing uses energy to form a pattern of growth and development.  Growth is the process of becoming larger.  Development is the process of change that produces more complex cells.  Multicellular organisms cells divide and to preform different functions.

Living things obtain and use materials and energy.  All living things take in materials and energy to grow and develop.  Autotrophs- are organism that make their own food.  Example: Plants capture the suns energy along with carbon dioxide and water to make their own food.  Heterotrophs- organisms that cannot make their own food.  Heterotrophs eat autotrophs or other heterotrophs that eat autotrophs.

Living things respond to their environment.  Organisms detect and respond to stimuli in their environment.  Stimulus- Is a change in an organism surrounding that cause a reaction.  Example: A plant bending toward the sun. Screaming or jumping when you are startled.

Living things maintain a stable internal environment.  Outside conditions may change dramatically but the internal conditions of an organism stay relatively the same.  This is called homeostasis.

As a group, Living things change over time.  The basic traits that an individual organism inherits usually do not change.  But over many years and generations groups of organisms typically change, this is evolution.