Transcript Human Anatomy and Physiology

Human Anatomy and Physiology
20A-2
Anatomy and Physiology
• Anatomy ~ how a structure is shaped, where it
is found and of what it is made.
• Physiology ~ concerned with the function of a
structure
• Anatomical position ~ a person standing, arms
at side, with toes, palms and face facing
forward. Giving the direction and area on a
human body using terms based on the body
being in the anatomical position.
Sagittal: divides body into
right and left portions
Box p627
Levels of Organization of Multicellular
Organisms
1. Cells ~ the basic unit of structure and
function of living organisms
2. Tissues ~ similar cells that are grouped
together to perform a similar function
3. Organs ~ tissues grouped together to perform
a specific function. One organ may contain
more than one type of tissue. The heart
contains tissues from all four groups.
4. Organ Systems ~ Groups of organs working
together to accomplish life functions.
Cellular
Organelle
Molecular
Atomic
Subatomic
Pronghorn
Antelope
Organism
Organ System
Nervous
System
Brain
Organ
Tissue
Nervous
Tissue
Biosphere
Earth’s
surface
Air
Ecosystem
Community
Bushes
Water Hawk
Snake
Pronghorns
Grass
Hawk
Snake
Population
Herd of Pronghorns
Pronghorns
Soil
Histology
• Histology ~ the study of tissues
• Vascular tissues- blood vessels run through
them (ex. Muscle tissue)
• Avascular tissues- lack blood vessels (ex.
Epithelial tissue)
4 Types of Tissue
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Connective
Epithelial
Muscle
Nervous
Connective Tissue
• Most abundant and diverse
• Support, connect, and protect other body
structures
• Usually connective tissue cells are not
adjacent to each other, but have matrix
between them.
Types of Connective Tissue
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Bone
Cartilage
Dense fibrous (ligaments and tendons)
Loose fibrous
Adipose (fat)
Blood
Lymph
Hemopoietic (blood forming)
Connective Tissue
Matrixes
Matrix ~ nonliving material present in tissue,
which is secreted by the tissue’s cells
Four types of matrix
1. solid matrix ~ example: bone
2. fluid matrix ~ example: blood ~ carries blood
cells
3. fibrous matrix ~ example: ligaments and
tendons ~ permits flexibility
4. gel matrix ~ example: cartilage of nose and
ear ~ soft mixed with fibers
Blood
Adipose (fat)
Cartilage
Bone
Tendons and Ligaments
Table p628
Epithelial Tissue
• Layers of cells that cover or line the external
and internal surfaces
• Vary in thickness from a single layer lining
capillaries to multiple layers forming the skin.
• Covers and lines to protect, secrete, absorb
and filter
Bladder
Trachea
Skin
Muscle Tissue
• Cells contract
• Move body or move fluid through the body
• 3 types
– Skeletal
– Smooth- typically involuntary
– Cardiac
Skeletal Muscle: Note that
the cells (running vertically)
are long, straight, striated
and multinucleated.
Cardiac Muscle: Note that
the cells are much more
branching than skeletal
muscle, but are still
striated. The key feature is
the dark lines that run across
the tissue between
cells. These are intercalated
discs and are only found in
cardiac muscle.
Smooth Muscle: Note that
striations are not present
(thus the name) and that
the cells are flattened and
stretched out (spindle
shaped).
Chart p647
Nervous Tissue
• Cells receive and transmit electrochemical
impulses from muscles, glands, and other
nerve cells
• Brain, spinal cord, and nerves
• Coordinates muscular movements, interprets
sensations received from the environment,
and controls thought processes and emotions
Table p628
Organ Systems
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Integumentary
Skeletal
Muscular
Respiratory
Digestive
Circulatory
Lymphatic
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Excretory
Nervous
Endocrine
Reproductive
Body Cavities
1. Cranial cavity ~ houses the brain
2. Spinal cavity ~ surrounds the spinal cord
3. Thoracic cavity ~ contains the heart,
respiratory organs and esophagus
4. Abdominal cavity ~ contains the digestive,
reproductive and excretory organs
*The thoracic cavity and abdominal cavity are
separated by the diaphragm.