Organization of Living Things

How are living things organized?
In order for us to discuss organization of living things, we must begin with the most basic cell, which is a prokaryote.
Prokaryotic cells are cells without nucleus (organelles). The only known prokaryotes are bacteria.

Pro - means before
Karyote - means nucleus

According to fossil records, prokaryotes (bacteria) were the first living things. They existed before the evolution of nucleus.

IMAGE OF PROKARYOTE
Eu - means true
Karyote - means nucleus

The next level of organization is eukaryotic cells. Cells with organelles or membrane bound structures. These cells have distinct compartments like nucleus, mitochondria and other organelles that help them carry out their life functions.

Some eukaryotics are unicellular or organisms that are made of one cell. Some eukaryotics are multicellular or organisms that are made of many cells.

IMAGE OF A UNICELLULAR EUKARYOTIC ORGANISM


IMAGES OF MULTICELLULAR EUKARYOTIC ORGANISMS


THE ORDER OF ORGANIZATION FOR MULTICELLULAR ORGANISMS FROM THE LEAST TO THE GREATEST.

FIRST - Organelles are the small organs inside the cell, or the membrane bound structures inside the cell. Ex. nucleus, mitochondria, chloroplast.

SECOND - Cell is the basic unit of life and it is made of organelles.

THIRD - Tissue is a group of the same cells working together to perform one function. Ex. fat tissue, muscle tissue. and nerve tissue,

FOURTH - Organ is a group of different tissues working together to perform one function. Ex. the heart is an organ and it has fat tissue, nerve tissue, and muscle tissue.

FIFTH - Organ system is a group of different organs working together to perform one function. Ex. the digestive system consists of the mouth, the esophagus, the stomach, the large intestine and the small intestine.

SIXTH - Organism is any living thing. All of these structures and systems are coordinated to make a functional organism.


Check This Interactive "HUMAN ORGANIZATION"

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