Download Homeostasis

October 21, 2015
• Journal Question: Why is your body
temperature always around 98.6
degrees Fahrenheit?
Introduction to Anatomy and
Physiology
What is Anatomy?
• Literally means to cut apart
• The study of internal and external
structures of plants and animals
• How living things are put together
Two Types of Anatomy
• Microscopic Anatomy: Study of
structures only seen with magnification
aids.
• Macroscopic Anatomy: Study of
structures visible to the naked eye
• Also known as Gross Anatomy
• Examples?
Would the following items fall under
Microscopic or Macroscopic
Anatomy?
Red Blood
Cell
Stomach
Bacteria
Lungs
Femur
Cardiac Muscle Tissue
Ear
What is Physiology?
• The study of how body parts function
• How the body works
How does anatomy relate to
physiology?
Structure (anatomy) determines
function (physiology)
• If the structure is not right, the function
can’t be right either.
• Abnormal structure and function =
disease
• Example: Sickle Cell
Homeostasis
• Physiological mechanisms that work to
maintain a constant internal
environment
• Examples?
Components of Homeostatic
Mechanisms
1. Receptor – detects stimuli and sends
signal on an afferent pathway to the
control center.
2. Control Center – interprets signal and
decides how to act.
3. Effector – information flows from the
control center along the efferent
pathway to the effector.
How do homeostatic mechanisms
work?
If the body detects that its normal setpoint is either to high or to low it will
respond.
Afferent
Pathway
Receptor
(Start)
Control
Center
Efferent
Pathway
Effector
Example
• When your body gets to hot, what
happens?
• Send signal to control center in the brain
• Brain signals a response
• Sweat is released and blood vessels get
bigger
Positive Feedback Loops
• Loop continues in the same direction
and increases magnitude of change to
the body
Negative Feedback Loops
• Loop moves in the opposite direction of
a stimulus
Determine if the scenario represents a positive or
negative feedback homeostatic system:
a.
A car starts rolling out of a driveway w/o a
driver. A person decides to respond by pushing
the car in the direction that makes it leave the
driveway faster.
b.
Your blood calcium level is low so your body
begins to break down bone tissue so that calcium
is released into the blood.
c.
A neuron is stimulated and sodium goes rushing
into the cell. The more it is stimulated the more
sodium goes rushing in, thus enhancing the
stimulus.
Metabolism
• In order to maintain homeostasis
many chemical reactions have to
take place in your body. These
chemical reactions are collectively
called your metabolism
Two Types of Metabolic
Pathways:
1. Anabolism – the process by which simpler
compounds are built up and used for growth,
repair and reproduction.
Examples - cellular respiration to ATP
2. Catabolism – the process by which complex
substances are broken down into simpler
substances.
Examples – hydrolysis of fats or glycogen.
Homeostasis Lab!
Understanding Anatomy and
Physiology Terminology
Prefixes
Abdomin/o - Abdomen
Angi/o - Vessel
Arthr/o - Joint
Cardi/o - Heart
Cyan/o - Blue
Cyt/o - Cell
Derm/o - Skin
Erythr/o - Red
Gastr/o - Stomach
Glyc/o - Sugar
Hepat/o - Liver
Hist/o - Tissue
Leuk/o - White
Mamm/o - Breast
Nephr/o - Kidney
Neur/o - Neuron
Oste/o - Bone
Phag/o - Swallow
Path/o - Disease
Rhin/o - Nose
Acro - Extremities
Brady - Slow
Dys - Difficult
Electro - Electric
Macro - Large
Micro - Small
Tachy - Fast
Peri- around
A or An- Without
Dia- Through
Suffixes
-algia: Pain
-ectomy: Surgical Removal
-itis: Inflammation
-graphy: the process of
recording
-ologist: One Who Studies
-otomy: Cutting Into
-ostomy: Surgically forming an
opening
-phobia: fear
Decoding Medical
Terminology
• When defining medical terms normally the
suffix is said first, followed by the combining
word.
• Example: Gastrologist - one who studies
the stomach
• If a medical term has a prefix and a combining
word you normally say it in the order it is
written.
• Example: Bradycardia - slow heart rate
• If there is a prefix, a combining word, and a
suffix, you say the suffix first and then the
prefix and then the middle word
• Example: Endoabdominalgia - pain within
Writing out Medical
Terminology
• When writing out medical terms for most
instances the suffix indicates the last part of
the term first.
• Example: Inflammation of the stomach is gastritis
• When putting together a combing word and a
suffix you do not use the letter “O” at the end
of the combing word if the suffix begins with a
vowel, but you use the letter “O” if the suffix
begins with a consonant
• Example: Gastr/o + -itis = Gastritis
• Example: Leuk/o + -cyte = Leukocyte
Practice with Decoding and
Writing Medical Terms
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Cranial Cavity
Abdominal Cavity
Diaphragm
Ventral Cavity
Thoracic cavity
Mediastinum
Vertebral Canal
Pelvic Cavity
Abdominopelvic cavity
Pleural Cavity
Pericardial Cavity
Body Cavities