Intro to Human Anatomy

Chapter 1

What’s the Difference?

ANATOMY PHYSIOLOGY Which has more new discoveries?

Anatomy or Physiology?

• To send a nerve impulse, sodium and potassium

ions must switch places in the cell

• The human tailbone is a fusion of multiple

vertebrae

• When the bicep muscle contracts, it pulls on

tendons and ligaments which move the lower arm

Homeostasis

• Maintaining a stable

internal environment

• Organ systems

function to maintain homeostasis

– Examples?

Homeostasis

•

Homeostatic mechanisms work by: 1. Having a set point (normal, balanced) 2. Receptors in the body detect deviations or stimulus

•

Increase or decrease past the set point 3. Trigger a set of events to bring the situation back to normal

Blood Sugar Regulation

Homeostasis

• NEGATIVE FEEDBACK – Correction occurs

opposite direction of stimulus

– Examples: • Body temp rises; cooling mechanisms activated • Body temp drops; heating mechanisms activated – Other examples?

Homeostasis

• POSITIVE FEEDBACK - Stimulus amplifies

response in the same direction

– Examples: • Chemicals present in a blood clot lead to more clotting • A baby drinking mother’s milk causes more milk

production

• Pressure in the uterus during childbirth leads to

stronger contractions

Homeostasis

• VITAL SIGNS – A measure of homeostasis – Indicate that someone is alive • What is measured in a test of vital signs?

Organization of the Body

• Lots of vocabulary to describe the body – Why? • Allows doctors to communicate as clearly as possible – Which would you rather hear as a surgeon? • “It hurts in the left upper side of my chest.” • “I’m having pain in the left lateral pleural cavity,

superior to the heart.”

Organization of the Body

• Many body cavities lined by membranes

PARIETAL – lines body cavity VISCERAL – covers organ

Organization of the Body

• Always refer to body

in ANATOMICAL POSITION

– Face forward – Palms forward – Note: Right and left

refer to the patient

Organization of the Body

• To observe

different sections, we cut the body along various imaginary planes

– SAGITTAL (median) – FRONTAL (coronal) – TRANSVERSE

(horizontal)

Organization of the Body

What does this mean?

The lesion is located in the right thorax just lateral to the mid-sagittal plane.