Transcript Introduction to Anatomy & Physiology

Anatomy & Physiology:
Understanding the Human Body
1
Definitions
Anatomy and physiology are interrelated subjects
Anatomy is the study of the structure of an
organism.
Physiology is the study of the function of an
organism.
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Levels of
structural
organization
3
Levels of structural organization
• Chemical level
– atoms and molecules
• Cellular level
– Cells: smallest living part of the body
• Tissue level
– Tissue: group of cells that work together to perform the same task
– 4 basic tissue types: epithelial, muscle, connective and nervous
• Organ level
– Organ: group of 2 or more tissue types that work together to perform
a specific function
System level
– Organ system: a group of organs working together to preform one of
the body’s major functions
– sometimes an organ is part of more than one system
• Organismal level – the organism OR living thing
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THE HUMAN CELL
All living organisms are composed of cells
 The cell is the smallest living part of our body
 It is the building block of
our entire body
 Cells vary in size, shape
and function
 All cells need food, water,
and oxygen to live and
function
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Structures of the cell - organelles
The cell can be considered as a factory with lots of machines inside,
each performing a different job
Cell membrane:
outer covering of the cell
holds substances inside
maintains the shape of the cell
The nucleus:
central portion of the cell
directs the cell’s activities
contains the chromosomes
 Chromosomes (made up of DNA): the bearer of genes, which
carry inherited traits such as eye colour
Cytoplasm:
surrounds the nucleus
contains machinery of the cell (organelles).
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Types of Cells
There are many different types of cells, each with a different shape
and function.
Types of cells:
 Nerve cells (neurons):
have long, thin
extensions that can
transmit nerve impulses
over a large distance
 Epithelial Cells: thin, flat,
and tightly packed so
that they form a
protective layer
 Muscle Cells: slender
rods that attach to the
ends of the structures
they move
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Types of tissues
Connective Tissue holds body parts together and connects them. Body parts
like bones, ligaments, and tendons are held together by this type of tissue.
Epithelial Tissue covers the internal and external body surfaces. Examples of
this tissue are the skin and the linings of internal organs.
Muscle Tissue expands and contracts, allowing the body to move.
Nervous Tissue carries messages from all parts of the body to the central
nervous system (CNS).
Organs and Organ Systems
Organ Systems
 have separate and distinct functions, but they rely on one another to perform
their tasks
 made up of organs