Section 2: The Study of Life How are the branches of life science related? What are some big ideas in life science?

What is Life Science? The study of living things Aka “Biology” Bio = life -ology = the study of Biology = the study of life If –ologist = a person who studies, then what would be the term for a person who studies living things?

Organism The general term for a living thing is an organism. An organism may be an animal, a plant, a fungus, or a microbe. How many different organisms can you name in this picture?

Branches of Life Science Though life science can be divided into branches, the different fields of study often overlap.

More branches of Life Science! What do you think these branches study? Microbiology Botany Ornithology Ichthyology Small Organisms Plants Birds Fish

Big Ideas in Life Science Your book discusses four big ideas in Biology…. Let’s look at them!

1) Diverse but similar Organisms are diverse, yet share similar characteristics All organisms are made up of cells, some of one cell, others of many All living things are mainly water, but with other chemicals too, such as DNA All living things need energy, some make their own, others must eat things All organisms grow and develop, some more complex than others All living things reproduce, some sexually, some asexually

2) Change over time Groups of organisms change over time This is a gradual process known as evolution This process is different from growth and development, because now we are no longer talking about individuals, but rather a species as a whole. And evolution happens slowly over many generations, not in one individual’s lifetime.

3) Complementary Structure and Function The structure and function of organisms is complementary, this means the form of each living thing is closely related to the way that is lives. Example- owls have large eyes which allow them to see better at night, which is when they hunt. Example- Humans have opposable thumbs which allow us to pick things up easily

4) Physical Principles Organisms operate on the same physical principles as the rest of the natural world Example- the principles of chemistry explain how plants use the sun to make food, and how DNA carries genetic info from parents to offspring. Example- the principles of physics help explain how light makes eyes functions, similar to how a camera uses a lens to focus light.