levels of Organization

1. any organism having as its fundamental structural unit a cell type that contains specialized organelles in the cytoplasm, a membrane-bound nucleus enclosing genetic material organized into chromosomes, and an elaborate system of division by mitosis or meiosis, characteristic of all life forms except bacteria, blue-green algae, and other primitive microorganisms.

1.1. Eukaryotes

2. any cellular organism that has no nuclear membrane, no organelles in the cytoplasm except ribosomes, and has its genetic material in the form of single continuous strands forming coils or loops, characteristic of all organisms in the kingdom Monera, as the bacteria and blue-green algae.

2.1. Prokaryotes

3. vocabulary

3.1. cell differentitation

3.1.1. is the process where a cell changes from one cell type to another.

3.2. stem cell

3.2.1. are undifferentiated biological cells that can differentiate into specialized cells and can divide to produce more stem cells.

3.3. tissue

3.3.1. an aggregate of similar cells and cell products forming a definite kind of structural material with a specific function, in a multicellular organism.

3.4. organ

3.4.1. a grouping of tissues into a distinct structure, as a heart or kidney in animals or a leaf or stamen in plants, that performs a specialized task.

3.5. organ system

3.5.1. is a group of anatomical structures that work together to perform a specific function or task.