“Introduction to Anatomy and Physiology”
What is anatomy and physiology?
• Anatomy: the study of the parts
of the human body and where
they are located.
• Physiology: the study of the
function or purpose of body parts.
“The body’s building blocks”
“The body’s building blocks”
• Molecules : the basic building blocks found in living and
nonliving things (everything on earth is comprised of molecules
as objects, trees, sugar, fat, water, and human bod.
• Cells: are found in all living things. Nonliving things don’t
contain cells. “Cells are comprised of group of molecules and
they’re very small that can be seen by microscope only”.
“The body’s building blocks”
 Cells types in human body are (fat cells, muscle cells, blood cell and bone cells).
 Cells contain of different parts:
A.
Cell membrane: cell skin or wall.
B.
Permeability: a membrane feature when wastes and nutrients (water& oxygen) pass through it.
C.
Cytoplasm: a jelly like material “holds small cell parts”
D.
Nucleus :cell’s brain, controls the cell and contains molecules (DNA); that tells the nucleus
how to do its job such as (breaking a part sugar or storing fat) .DNA is also a genetic material
that makes each person different from another.
* Red blood cell doesn’t have nucleus.
E.
Organelles: small cell parts that are held in the cytoplasm.
“Diagram of a cell and its parts”
“Overview of Cell Structure”
• https://www.youtube.com/watch?v=URUJD5NEXC8
“The body’s building blocks”
• Tissue: cells that look alike, joined
together, and have the same function.
• E.g. muscle tissue, blood tissue, fat
tissue and bone tissue.
https://www.youtube.com/watch?v=tKWTJ3_-1E8
“The body’s building blocks”
• Organ: a group of different tissues joined together to
carry out a specific function within the body.
• E.g. heart is an organ comprised of blood tissue,
muscle tissue, connective tissue and epithelial tissue.
These tissues form the function of pumping blood.
• E.g. small intestine comprised of epithelial tissue,
connective tissue, nerve tissue and muscle tissue. It’s
function is to absorb nutrients from food.
“The body’s building blocks”
• Organ system: a group of different organs that
work together to carry out a function in the body.
• E.g. the heart and blood vessels comprise the
circulatory system.
• E.g. the mouth, stomach, and intestines are part
of the digestive system.
What is Homeostasis?
• Homeostasis: the way the body keeps in balance
(maintain the same condition).
• Homeo= (same) , stasis= (condition)
• The body needs to keep constant levels of:
1. Temperature.
2. Water.
3.
Blood pressure.
“Homeostasis”
 What does the body do when it gets too hot?
1. You sweat and water leaves your body.
2. As the sweat dries on your skin, it cools your body
down to its proper temperature “set point” 37 Celsius.
 What does the body do when it gets too cold?
1. You start shivering.
2. The shivering movements produce heat.
3. The produced heat causes your body temperature to
rise until you reach the set point 37 Celsius.
Homeostasis video
• https://www.youtube.com/watch?v=taLTBoqakSY
Maintaining Homeostasis: Negative feedback
• Negative feedback: the process when the body senses an imbalance.
• Negative= (bad) , Feedback= (information).
• The body uses negative feedback to constant different amounts in our body as the
amount of nutrients, hormones, blood pressure, heart and breathing rate.
• Example,
1.
When people exercise, their body might notice the need for more oxygen. (
negative feedback).
2.
Homeostasis process occurs to improve this situation.
3.
The heart beats faster and you start breathing faster to provide your cells with
more oxygen.
Maintaining Homeostasis: Reflex
Homeostasis is usually maintained by negative feedback in the form of reflex.
Reflex: an automatic event/a series of automatic events in the body that
helps to maintain/restore homeostasis.
When does it happen?
It happens when the body makes a change without your having to think
about it (automatic).
Reflexes are one way that the body responds to negative feedback and
maintains homeostasis.
“Steps in a Reflex When Touching Fire”
1. Sensors in your finger feel the pain and heat of fire. Too much pain and heat! (negative
feedback). The part of the body that can fix this problem must be notified.
1.
To correct this condition, nerves in your finger send a message about the pain and
heat to your spinal cord.
2.
The spinal cord interprets this message "it makes the decision to move the finger
away from the fire”.
3.
The spinal cord sends a message ( make the finger move). This message is carried a
long a nerve to the muscle that can cause the finger to move.
4.
The muscles receive the message; they contract and the finger moves away from the
fire.
“Homeostatic Messengers”
There are two ways to send messages to correct negative situations:
1.
Through the nerves .
• Nerves: are organs that quickly send messages from and to the spinal
cord or brain.
• Neural messages are so fast and their effect stays for a short time.
• E.g. “moving a finger from the fire”.
“Homeostatic Messengers”
2. Through the hormones.
• Hormones: are molecules which are produced by
endocrine glands and secreted into the blood stream.
• E.g. when the body notices more sugar in the blood, the
pancreas secrets the hormone insulin into the
bloodstreams.
• Hormonal messages are slow, and their effect stay
longer.