Notes 1 - Introduction to Biology

How our notes will be set up... We always start with “Central Questions”, which you will answer at the end Key terms usually show up in blue. Anything that is in blue, must be highlighted. Text in red are essential facts.

Central Questions What does biology study? What are the characteristics of living things?

What is Biology? Biology is the study of living things and their interactions with the world around them. Bio=life; ology=study of A Biologist is someone who uses the scientific method to study life.

Branches of Biology  Zoology  Ecology  Botany  Paleontology  Cytology  Microbiology  Virology  Biochemistry  Genetics  Physician  Veterinarian  Medical researchers  Wildlife managers  Forester  Agricultural researchers  Breeder Pure ScienceApplied Science

Characteristics of Living Things 1.Composed of Cells 2.Reproduce 3.Based on the Genetic Code 4.Grow and Develop 5.Obtain and Use Energy 6.Respond to their Environment 7.Maintain Homeostasis 8.Evolve

1. Composed of Cells The cell is the smallest unit of life Organisms can be: 1.Unicellular: has single cell 2.Multicellular: has many cells

2. Living Things Reproduce Two Types of Reproduction 1.Sexual Reproduction Animals Requires two parents Sex cells combine to produce offspring 2. Asexual Reproduction Bacteria Requires only one parent Parental cell splits into two

3. Based on the Genetic Code Deoxyribonucleic Acid (DNA) In asexual reproduction, the offspring are genetically identical to the parents In sexual reproduction, the offspring are not identical to the parents.

4. Grow and Develop

5. Obtain and Use Energy Heterotrophs—acquire food Autotrophs—make food

6. Respond to the Environment A stimulus is any signal to which your body responds

7. Maintain Homeostasis Homeostasis: keeping internal conditions the same as outside changes  Example: water level, internal temperature

8. Evolve Evolution: change over time

Levels of Organization Molecules – atoms, subcellular Cells – basic unit of life Tissues – groups of cells Organs – groups of tissues Organ Systems – groups of organs Organisms – individual living things Populations – same species, in an area Communities – living things, in an area Ecosystems – both living and nonliving Biosphere – anywhere on Earth there’s life SMALL BIG

Central Questions What does biology study? What are the characteristics of living things? Answer these questions at the bottom of your notes.