WHAT IS PHYSIOLOGY?
• Study of specific characteristics and
mechanisms of human body that make it a
living being .
OBJECTIVES
1. Define: Cell, Tissue,
organ, and organ system,
homeostasis
2. Describe types of tissue
3. What are organs?
4. Describe organ system
Organization of Vertebrate Body
There are four levels of organization:
1. Cells
2. Tissues
3. Organs
4. Organ systems
Bodies of vertebrates are composed of
different cell types
-Humans have 210
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Levels of Organization
• CELL—Basic unit of structure and function in
organisms.
– Some organisms, like bacteria and protists, are unicellular (made
entirely of one cell).
– Some organisms, like fungi, plants, and animals, are multicellular
(made of many cells).
– In multicellular organisms, cells exhibit cell specialization. They
take on specific jobs and look different from each other.
Levels of Organization
• TISSUES—Groups of similar cells that
work together to perform a specific
function
– 4 major/primary tissue types in animals
•
•
•
•
Epithelial tissue
Connective tissue
Muscle tissue
Nervous tissue
Levels of Organization
• ORGANS— a structural and functional unit.
• made of different types of tissues that work together to
perform a specific function.
– Examples
•
•
•
•
•
•
•
•
•
•
Heart
Lungs
Stomach
Small intestine
Liver
Large Intestine
Gall Bladder
Plant Roots
Plant Stems
Plant Leaves
Levels of Organization
• ORGAN SYSTEMS—Groups of organs that
work together to perform a specific function.
• The vertebrate body contains 11 principal organ
systems
– Examples:
• Digestive system
• Circulatory system
• Respiratory system
• Nervous system
• Muscular system
• Skeletal system
• Integumentary system (skin)
Levels of Organization
• AN ORGANISM—A complete, individual
living thing.
• Examples:
– A single person
– A single plant
– A single bacterium
– A single protist
TISSUES
EPITHELIAL
CONNECTIVE
MUSCLE
NERVOUS
Epithelial Tissue
An epithelial membrane, or epithelium,
- covers every surface of the vertebrate body
-Some epithelia change into glands
-Provide a protective barrier
-remarkable regenerative powers replacing
cells throughout life
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Epithelial Tissue
Two general classes
-Simple = One layer thick
-Stratified = Several layers thick
Subdivided into:
-Squamous cells = Flat
-Cuboidal cells = Cube-shaped
-Columnar cells = Cylinder-shaped
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Where do find Epithelial tissue?
List two places to find Epithelial tissue
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Stratified Epithelium
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Connective Tissue
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CONNECTIVE TISSUE TYPES
• CONNECTIVE TISSUE PROPER:
-Adipose
-Loose connective tissue
-Dense connective tissue
• SPECIAL CONNECTIVE TISSUE:
-Cartilage
-Bone
-Blood
Connective Tissue Proper
Adipose cells (fat cells) also occur in loose
connective tissue
-Develop in large groups in certain areas,
forming adipose tissue
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Connective Tissue Proper
-Dense regular connective tissue
-Makes up tendons and ligaments
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Special Connective Tissue
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Muscle Tissue
Smooth muscles
-found in walls of blood vessels and visceral organs
-Cells are mono-nucleated
Skeletal muscles
-Most voluntary functions
-Cells are multi-nucleated
Cardiac muscle
-composed of smaller, interconnected cells
-Each with a single nucleus
-Enable cardiac muscle cells to form a single functioning unit
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Nerve Tissue
• Cells include neurons
• supporting cells called neuroglia
-Support and provide insulating cover called the myelin
sheath
Most neurons consist of three parts
-Cell body: contains the nucleus
-Dendrites: highly branched extensions
-Conduct electrical impulses toward the cell body
-Axon: single cytoplasmic extension
-Conducts impulses away from cell body
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Organ Systems
1-Communication and integration
-Three organ systems detect external stimuli and coordinate the body’s
responses
-Nervous, sensory and endocrine systems
2-Support and movement
-The musculoskeletal system consists of two interrelated organ systems
3-Regulation and maintenance
-Four organ systems regulate and maintain the body’s chemistry
-Digestive, circulatory, respiratory and urinary systems
4-Defense
-The body defends itself with two organ systems: integumentary and immune
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Write your answers in complete sentences
•
Q 1: A (tissue, organ, system) is a group of the same kinds of cells that work together.
Choose the right answer.
system
organ
tissue
Q 2: Some tissues and organs work together like the members of the team. The parts
that work together are called a _____________.
cell
system
group
Q 3: The mouth, teeth, tongue, stomach and intestines all work together. Therefore they
are called the important parts of __________________.
digestive system
circulatory system
muscular system
Q 4: Brain, heart and lungs are some of the important _______________ in a body.
organs
tissues
cells
system
Q 5: Different tissues work together to form _________ .
cells
system
organs
Q 6: Different systems work together to form organs. True or false?
false
true