Transcript Chapter 1 - Levels of Organization

Introduction to Human Anatomy
and Physiology
Anatomy: The study of structure
Physiology: The study of function
How are they related?
A body structure is
specifically adapted
for its function.
Ex: the hand
grasps while the
heart pumps blood.
What characteristics
make you a living thing?
How do we know you are
alive?
Characteristics of Life
1. Movement
• Walking, endo/exocytosis, heart beat
2. Responsiveness • Reaction to a stimulus internal/external
3. Growth
• Increase in body/cell size; cell material or cell
number
• Mitosis (repair/replace), meiosis, a new life
4. Reproduction
5.
6.
7.
8.
9.
Respiration
Digestion
Absorption
Circulation
Assimilation
10. Excretion
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Obtaining oxygen and releasing energy from foods
Breakdown of food substances. (catabolic)
Moving through membranes.
Moving within body fluids. (blood or lymph)
Changing absorbed foods into other chemical
structures. (anabolic)
• Removing wastes from metabolic reactions.
Everyday example using the
characteristics of life…
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I am walking to In and Out Burger (movement)
I stop at the traffic light (response)
My body is growing because I am young (growth)
I am breathing air (respiration)
I eat a Double-Double (digestion)
My body absorbs the hamburger (absorption)
The hamburger nutrients circulate in my blood
(circulation)
• The hamburger is changed to things my body
needs (assimilation)
• Eventually, I go to the bathroom (excretion)
• I picked a scab that wasn’t ready. (reproduction)
Metabolism:
• All the physical and chemical changes.
• All the body processes that use energy to
function.
• It is your engine! The speed of your engine
is regulated by all the characteristics.
What environmental
requirements must be met so
that you can stay alive?
Environmental Requirements
1.
Water
2. Food
3. Oxygen
4. Heat
5. Pressure
• Solvent for reactions, transport,
temperature regulation.
• Building material, energy, enzymes
• Releases energy from foods.
• Regulates speed of
metabolism/reactions.
• Force needed for breathing and
blood circulation.
What is HOMEOSTASIS?
Physiological principle that systems strive
to maintain relatively constant internal
environment.
It is a balancing act!
Adaptations to
sudden or
gradual changes
must be met!
Homeostasis usually operates to keep
vital stats within a narrow range for
normal function.
Ex: Normal pH of blood is about 7.4
pH of 6.7 or 8.0 would
mean death!
Homeostasis control is mainly by the
nervous and endocrine systems.
What can cause homeostasis to become
unbalanced?
• Age, diet, stress, disease or disorders.
How does Homeostasis work?
1. Receptors – messengers that pick up
imbalance; send info to control center.
2. Control Center – interprets and sends out a
response
3. Effectors – carries out response
4. Set Point – ideal internal value
5. Negative Feedback - process to return set
point to normal. (Effectors cause an opposite
response to stimulus; stimulus is reduced.)
6. Positive Feedback – stimulus is increased or
reinforced by the effectors. Not very common.
Is this an
example of
negative or
positive
feedback?
Is this a negative or
positive feedback
loop?
What do you think the effectors will be
told to do if BP gets too low?
Positive Feedback
1.
How does the
action of the
effectors
compare to the
original
stimulus?
2.
Is homeostasis
being restored?
Blood Clotting
Process…
Question: Why is
positive feedback
helpful in clotting blood,
but unsuitable for
regulation of body
temperature?
What are the
control centers?
Effectors?
•
During lactation (milk production), the
suckling by the baby stimulates the
production of oxytocin, which in turn
causes contraction of smooth muscle
surrounding the milk duct, causing milk
to flow. The flow of milk increases the
suckling by the baby and more oxytocin
is produced.
Is this negative or positive
feedback loop?
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When blood glucose levels rise above a set
point after eating a meal high in carbohydrates,
beta cells in the pancreas are activated and
release insulin into the blood. Insulin causes
an increase in glucose uptake by body cells
and causes the liver to take in glucose and
convert it to glycogen. As a result, blood
glucose levels decline to the set point.
1. Is this a negative or positive feedback loop?
2. What is the control center?
3. What is the effector?
How is the body
organized?
Levels of Organization
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Smallest to largest:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Atoms
Molecules
Macromolecules
Organelles
Cells
Tissues
Organs
Systems
Organism
How would you order
these?
osteocyte
calcium
femur
bone tissue
skeleton
Organ Systems
1. Body Covering
2. Support/Movement
3. Integration/Coordination
4.
Transport
5.
Absorption/Excretion
6.
Reproduction
• Integumentary
• Skeletal, Muscular
• Nervous,
Endocrine
• Cardiovascular,
Lymphatic
• Digestive,
Respiratory,
Urinary
• Reproductive
• Axial Portion - head,
neck, trunk
• Appendicular Portion arms & legs
Dorsal
Cavity
Body Membranes
Serous membranes line and cover cavities
and organs. Two layers with a serous fluid
for lubrication.
1. Parietal – membrane attached to the wall of
a cavity. Lines the cavity the organ is in.
2. Visceral – membrane that covers an organ.
These terms are further associated with:
– Pleura – lungs
– Pericardium – heart
– Peritoneum - abdomen
Body Regions
How are the location of
body parts described in
relative to another body
part?
Must refer to correct
ANATOMICAL POSITION
Positional Terms
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Superior – toward the top or head region
Inferior – toward the bottom or feet
Anterior or Ventral – front side
Posterior or Dorsal – back side
Medial – closer to midline
Lateral – farther from midline
Proximal – body part is closer to the point of
limb attachment than other body part
• Distal – body part farther from the point of limb
attachment than other body part
• Superficial – closer to the surface
• Deep – deeper in the body
Coronal Plane
(front/back)
Sagittal plane (right/left)
(top/bottom)
What type of
section is
shown here?
What type of
section is
shown here?
What type of
section is
shown here?
What type of
section is
shown here?