Properties of life What makes something alive Biology

Properties of life What makes something alive?

Biology • Biology: – “Bio” is a latin prefix that means life. – The “-ology” suffix means “the study of”. • Biology is the study of life, but what is really considered “alive”? – Are plants considered alive? – How about bread mold? – What about rust on iron?

More complicated than you thought… • Some things may seem like they’re alive, but really aren’t. – In order to make things simpler, biologists have come up with set characteristics that help to determine if something is alive or not.

The 7 properties of all living things • • Cellular organization Homeostasis Metabolism Responsiveness Reproduction Heredity Growth

Cellular organization • Cells are the smallest unit capable of all life units – Cells are highly organized, tiny structures, enclosed in a thin membrane. – They are the basic structure of all living things. – The cells of all living things contain the same basic properties.

Homeostasis • All living organisms must maintain a stable internal environment in order to function properly. – If you get hot what does your body do to maintain temperature homeostasis? – If you drink too much water, what does your body do to maintain homeostasis?

Metabolism • Living things must carry out many chemical reactions in order to obtain energy. • Metabolism is the sum of all these chemical reactions. – Where to plants get their energy from? – What about animals? – Where does all energy come from?

Responsiveness • Living organisms must respond to their environment. – How do you respond if its very cold outside? – How do plants respond to sunlight?

Phototropism

Reproduction • Most living things can reproduce. – Reproduction is the process of making more of their own kind. – No organism lives forever, so reproduction is an essential part of life.

Heredity • When an organism reproduces, it passes on its own traits to its offspring. This is known as Heredity. – Inheireted characteristics change over generations. – The process is called evoloution.

Growth • All living organisms grow. – Some things grow briefly. – Other organisms grow for hundreds of years. • As organisms grow, they change. This is called development. – Development differs from evolution because development happens to an individual over a lifetime – Evolution happens to a population, over several thousand lifetimes.