Structural levels

Many functions in a multicellular organism are complex. Groups of different kinds of tissues work together as an _________ to perform these functions. ________ exist only in multicellular organisms.

The stomach is an _________ in the digestive system.

^_________ are made of many related kinds of cells working together to perform specific functions. _______exist only in multicellular organisms.

Fatty _______ stores fat, and cushions and insulates organs.

An _____ is a particle that is the basic building block of all matter. ______are very, very small, ranging from approximately 0.1 to 0.5 nanometers in diameter.

A ________ is a particle that is made of two or more smaller particles held together by chemical bonds. _________ made of two particles can be tiny, while __________ made of many particles can be huge.

The glucose _________ is a molecule that is approximately 0.7 nanometers wide.

An _____________ is a group of organs that works together to perform complex functions. _______________ exist only in multicellular organisms.

The circulatory system transports substances to all the cells in the body.

_________ are components of cells. Different kinds of cells may be made of different kinds of _________.

This _________ is a cell membrane. It protects the cell from the environment and allows substances to enter and exit the cell. It is about 7 nanometers thick.

A ____________ can be considered a system made up of subsystems.

We humans are _______________.

The _______is the smallest thing that can be considered living.

This human cheek _____is one of the many kinds
of ______ found in humans. It is typically 40–50 micrometers in diameter. The cheek ____ is a typical animal ____.

What is the smallest thing considered to be living?

• Atom

• Molecule

• Cell

• Tissue

What is the order of the structural levels from smallest to largest?

• Molecule

  Organ

  Atom

  Tissue

  Cell 

  Multicellular Organism

  Cell Structure

  Organ System 

  
  

• Molecule

  Atom

  Cell

  Tissue

  Multicellular Organism

   Cell Structure

  Molecule

  Organ System

  Organ

• Tissue

  Molecule

  Organ System

  Organ

  Cell 

  Multicellular Organism

  Atom

  Cell Structure

   

  
  

• Atom

  Cell

  Cell Structure

  Molecule

  Multicellular Organism

  Organ

  Organ System

  Tissue