The document outlines the different levels of organization of life, from the smallest subatomic particles up to larger biological groups. It begins by listing the levels in order from smallest to largest: subatomic particles, atomic particles, organelles, cells, tissues, organs, systems, organisms, families, populations, biocenoses, ecosystems, and biosphere. It then provides more details about the characteristics and components of each level.

1. Levels of Organization of Life
David Suescún Pelegay Página 1

2. Levels of Organization of Life
First, we are going to see a scheme of the levels of organization of life.
⇒ Subatomic particles.
⇒ Atomic particles.
⇒ Organelles.
⇒ Cell.
⇒ Tissue.
⇒ Organ.
⇒ System.
⇒ Organism.
⇒ Family.
⇒ Population.
⇒ Biocenosis.
⇒ Ecosystem.
⇒ Biosphere.
And now, we are going to see each one with careful.
David Suescún Pelegay Página 2

3. Levels of Organization of Life
The subatomic particles are the smaller part of anything. It is composed by:
Electrons: The electron is a subatomic particle, which has a negative mass.
Protons: The proton is a subatomic particle, which has a positive mass.
Neutrons: The neutron is a subatomic particle, which has a negative mass.
Now, we are going to see the characteristics of each subatomic particle.
Load Load (numbers) Weight
Electron ∗ 9,1 ∙ 10
1,602 ∙ 10
-
Proton ∗ 1,6 ∙ 10
1,602 ∙ 10
+
Neutron 0 1,6 ∙ 10
0
Coulomb*= The coulomb is the unit of electric charge. It is defined as the charge
transported by a steady current of one ampere in one second.
The subatomic particles are the base of everything.
This is an image of an atom of helium. The green balls
are the neutrons, the red balls are the protons and the
yellow balls are the electrons.
David Suescún Pelegay Página 3

4. Levels of Organization of Life
The atomic particles are formed by the union of subatomic particles.
The atomic particles are the atoms and the molecules. We are going to see each one:
Atom: The atom is a basic unit of matter that consists of neutrons, electrons
and protons. The atom has to parts: the nucleus, which contains the neutrons
and the protons, and the cortex that contains the electrons.
An example of atom is !".
Molecule: A molecule is a neutral group or two or more atoms.
An example of molecule is $ % & ' ".
This is a molecule of water.
David Suescún Pelegay Página 4

5. Levels of Organization of Life
The organelle is a specialized subunit inside a cell, everyone has an specific function.
Every organelle has an specific function:
Name Function
Nucleus Contains DNA*, controls the activity of the cell.
Chloroplast Make photosynthesis, traps energy from sunlight.
Golgi apparatus Sorting and modification of proteins.
Mitochondria Energy production from the oxidation of food substances.
Vacuole Storage water. Help to maintain homeostasis.
Centriole Anchor for cytoskeleton, helps in cell division by forming spindle
fibers.
Lysosome Breakdown of large molecules.
Nucleolus Ribosome production.
Ribosome Translation of RNA* into proteins
DNA*= Deoxyribonucleic acid.
RNA*=Ribonucleic acid.
An animal cell. Within the cytoplasm, the
major organelles and cellular structures
include: (1) nucleolus (2) nucleus (3)
ribosome (4) vesicle (5) rough
endoplasmic reticulum (6) Golgi
apparatus (7) cytoskeleton (8) smooth
endoplasmic reticulum (9) mitochondria
(10) vacuole (11) cytosol (12) lysosome
(13) centriole.
David Suescún Pelegay Página 5

6. Levels of Organization of Life
The cell is the basic structural and functional unit of all known living organism. It is the
smallest unit of life that is classified as a living thing, and is often called the building
block of life. Humans contain about 100 trillion cells; a typical cell size is 10 ( and a
typical cell mass is 1 monogram.
The cells could be classified into:
Eukaryotic: The eukaryotic are cell which contains a nucleus. The eukaryotic cell
could be:
Animal eukaryotic cells: The animal cells don’t have a vacuole, because the
reserves of water are bigger.
Plant eukaryotic cells: The major difference is that this type of cells has
vacuole to store water.
Prokaryotic: The prokaryotic are cells which don’t contain nucleus.
This are three examples of cells: (up
left) is an animal cell, (up right) is a
plant cell, both of them are eukaryotic,
the image at the left is from a bacteria,
don’t contain nucleus, and it is
prokaryotic.
David Suescún Pelegay Página 6

7. Levels of Organization of Life
A tissue is group of cells.
A tissue is a cellular organizational level intermediate between cells and a complete
organism. A tissue is an ensemble of cells, not necessarily identical, but from the same
origin, that together carry out a specific function. The tissue could be classified into
four parts:
Connective tissue: Are fibrous tissues. They give shape to organs; blood and
bone are examples of connective tissue.
Muscle tissue: Are made up of contractile tissue of the body. This tissue moves
to produce forces and cause motion, locomotion. The heart is a muscle tissue,
allowing pumping the blood.
Nervous tissue: These tissues are only used in the CENTRAL NERVOUS
SYSTEM and in the PERIPHERIAL NERVOUS SYSTEM, are used to transmit
information.
Epithelial tissue: Are formed by cells that cover organ surfaces such as the skin,
the airways, and the digestive tract. These tissues help to protect organism from
bacteria.
This image shows the different types of tissue looked thought a telescope. The
composition is different.
David Suescún Pelegay Página 7

8. Levels of Organization of Life
The organs are group of tissue.
Usually there is a main tissue (parenchyma) and sporadic tissues (stroma). For
example, the main tissue in the heart is the myocardium; a group of organs cooperate
to form systems.
This image shows the principal organs of our body.
David Suescún Pelegay Página 8

9. Levels of Organization of Life
A system is a group of organs.
These organs work together to make a specialized job.
In the human body, they are many systems, the principal are:
Circulatory System: Is the system which pumps blood.
Digestive System: Is the process which the food breaks down to be digested.
Endocrine System: Is the communication within the body using hormones
made by endocrine glands…
Excretory System: Gets rid of waste in the body; contains the digestive,
respiratory and urinary system.
Nervous System: This system collects, transfer and process the information
with the brain, the spinal cord and the peripheral nervous system.
Respiratory System: Are the organs used for breathing, the lungs, pharynx,
larynx, trachea, bronchi and diaphragm.
Skeletal System: Is the structural support and protection: bones, cartilage,
ligaments and tendons.
Urinary System: Are the organs that maintain the fluid balance and excretion of
urine.
This is an image that shows
the different systems of
the body.
David Suescún Pelegay Página 9

10. Levels of Organization of Life
An organism is a group of systems.
An organism is any living being. In at least some form, all organism could response to a
stimuli, reproduction, growth and development, and maintenance of homeostasis as a
stable whole.
This are organism.
David Suescún Pelegay Página 10

11. Levels of Organization of Life
A family is a group of organism.
Are group of living being that are like to the living being of its family.
This is a classification of the families.
This the Simpsons family tree.
David Suescún Pelegay Página 11

12. Levels of Organization of Life
Population is a group of families.
David Suescún Pelegay Página 12

13. Levels of Organization of Life
Biocenosis is a group of population.
Biocenosis describes the interacting organism living together in a habitat.
David Suescún Pelegay Página 13

14. Levels of Organization of Life
An ecosystem is a group of biocenosis.
An ecosystem is a biological environment consisting of all the organisms living in a
particular area, as well non-living beings.
The ecosystems could be very small or very big.
These are examples of
ecosystems.
David Suescún Pelegay Página 14

15. Levels of Organization of Life
The biosphere is a group of ecosystems.
The biosphere is the global sum of all ecosystems. It can also be called the zone of life
of Earth.
The Earth as a biosphere.
David Suescún Pelegay Página 15

16. Levels of Organization of Life
David Suescún Pelegay Página 16