Body Systems
Introduction
and Circulatory
System
Biological Structures
 Biological
Structure
parts within a living organism or cell
 Examples:
Kidney, lung, mitochondria, chloroplast
 It
that makes up a living thing, or a living thing
itself
Order of Biological Structures
 From Smallest

to
Largest
 Cell Tissue Organ Organ
System Organism
Organelle
Order of
Biological
Structures
 Draw
a
picture that
helps you
remember
the order of
Biological
Structures
Order of Biological Structures

Organism- a living unit/species that is completely
functional with all necessary parts

System-a group of related body parts that work together
to form a specific function

Organ- part of an organism that has a specific vital
function (ex: heart, lungs, etc.)

Tissue- specialized cells and their products forming a
certain material in the body

Cells- the smallest unit of life
Benefits of Specialized Cells
 Specialized
Cells-multicellular organisms have
cells that can become specialized for a specific
task
 Example: Kidney Cells, Heart Cells, Lung Cells
 This allows for specialized body parts: kidneys,
heart, and lungs.
 Organisms with specialized cells live longer.
 Why do you think this is?
Benefits of having Specialized Cells
 Benefits:
1.
Organism has specific and unique parts
2.
Species can be both male and female
3.
Organism can have specific body systems
(Excretory, Digestive, etc.)
4.
They tend to live longer because the cells
can focus on one task
12 Body Systems
 Circulatory
 Digestive
 Excretory
 Respiratory
 Nervous
 Muscular
 Integumentary
 Skeletal
 Lymphatic
 Immune
 Reproductive
 Endocrine
Circulatory System
 Organs/Parts:
Heart
 Blood vessels: arteries and veins
o Function:
 Circulates blood
throughout the body

Circulatory System Continued
 Heart-
A hollow, muscular
organ that pumps blood
throughout the circulatory
system
 http://www.youtube.com/
watch?v=oE8tGkP5_tc
Circulatory System Continued
 Arteries:
carries blood Away from heart
 Oxygenated blood
 Carried under great pressure
Circulatory System Continued
 Veins:
 Carries
de-oxygenated blood (CO2)
towards the heart
 Not under a lot of pressure; has valves to
work against gravity
Circulatory System Continued
Why is
the
artery so
much
thicker
than the
vein?
Key Ideas