Organization of the Organism

To produce energy for the cell

To store genetic information and control cell activities

To allow substances to enter and leave the cell

To synthesize proteins for secretion

Cell $\rightarrow$ Tissue $\rightarrow$ Organ $\rightarrow$ Organ System

Organ $\rightarrow$ Organ System $\rightarrow$ Tissue $\rightarrow$ Cell

Tissue $\rightarrow$ Cell $\rightarrow$ Organ System $\rightarrow$ Organ

Cell $\rightarrow$ Organ $\rightarrow$ Tissue $\rightarrow$ Organ System

Cell membrane

Cytoplasm

Cell wall

Nucleus

The brain

A nerve cell

Spinal cord tissue

The nervous system

A leaf

A root hair cell

The xylem

The phloem

Organ system $\rightarrow$ Organ $\rightarrow$ Tissue $\rightarrow$ Cell

Cell $\rightarrow$ Tissue $\rightarrow$ Organ $\rightarrow$ Organ system

Tissue $\rightarrow$ Cell $\rightarrow$ Organ system $\rightarrow$ Organ

Cell $\rightarrow$ Organ $\rightarrow$ Tissue $\rightarrow$ Organ system

Centimeters ($cm$)

Meters ($m$)

Millimeters ($mm$)

Micrometers ($\mu m$)

$0.2\ mm$

$2\ mm$

$0.02\ mm$

$200\ mm$

$10\ \mu m$

$1000\ \mu m$

$100\ \mu m$

$10000\ \mu m$