1. Levels of Biological Organization
All the levels of biological organization will be introduced at the beginning of the year. These are the different levels at which you can study biology. If one level is effect by some sort of change, the change will have an effect on each of the levels in a related way (drought in the ecosystem, dehydration in the organism, cells lose water, etc).
For unit 1, focus on the macroscopic levels (starting at organism and ending at biosphere).

2. Organelle Structures with particular functions with in cells
Membrane-bound organelles are found in eukaryotic cells
Examples include the mitochondria, chloroplast and nucleus

3. Cell Basic unit of all organisms Smallest living thing
Simple cells are Prokaryotes and complex cells are Eukaryotes

4. Tissue
A group of the same type of cells that work together to perform a specific function
Examples of tissues in animals include muscle, bone, epithelial, and nervous tissue
Plants and Fungi also have tissue

5. Organ
A group of two or more tissues working together to perform a specific function
Examples of organs in animals include the stomach, the heart, the brain, and the skin
Plants also have organs such as roots, stems and leaves

6. Organ System
Multiple organs that work together to perform a specific function
Examples of organ systems in animals include the digestive, immune, and nervous system
Plants also have organ systems (ex: vascular system)

7. Organism A living thing
Anything that possesses all the characteristics of life
Organisms can either be animals, plants, fungus, protists, bacteria or archae

8. Population
A group of organisms, all of the same species, living in the same place at the same time
These organisms can interbreed

9. Community
A group of several populations living in the same place at the same time
Communities make up food chains and food webs
Communities only include the biotic (living) things

10. Ecosystem
All of the biotic (living) and abiotic (non-living)factors interacting in the same place at the same time
Biotic = living (ex: grass, snail, frog)
Abiotic = nonliving (ex: rock, climate, landforms)

11. Biosphere The portion of Earth that supports life
This includes high in the atmosphere to deep in the oceans
We live in the biosphere

12. Biosphere The portion of Earth that supports life
This includes high in the atmosphere to deep in the oceans
We live in the biosphere