Lecture 2 Flashcards
What is homeostasis?
A state of equilibrium; maintenance of relatively stable internal conditions despite continuous changes in environment
Examples of homeostasis
-body temperature
-blood levels of calcium, sodium, glucose, etc
-blood pressure
-water balance/hydration
What are the components of a control mechanism?
- receptor
- control center
- effector
What does the receptor do?
The receptor is the sensor, which monitors the environment and responds to stimuli
What does the control center do?
The control center determines a set point at which variable is maintained, and receives input from the receptor. From there it determines appropriate response.
What does the effector do?
The effector receives output from the control center and provides the mean to respond.
What is the order of the control system?
- stimulus
- receptor
- input
- output
- response
What does the stimulus do?
produces change in variable
What does the receptor do?
detects change
What is the input?
information sent along afferent pathway to control center
What is the output?
information sent along efferent pathway to effector
What is the response?
The response of the effector feeds back to reduce the effect of stimulus and returns variable to homeostatic level
Negative feedback
reduces or shuts off original stimulus; variable changes in opposite direction of initial change
Positive feedback
increases original stimulus if negative feedback is overwhelmed
Ventral
toward or at the front of the body
Dorsal
toward or at the back of the body
Intermediate
between a more medial and a more lateral structure
Proximal
closer to the origin of the body
Distal
farther from the origin of the body
The lungs are ____ to the skin.
deep
The elbow is ________ to the wrist.
proximal
The skin is ___________ to the skeletal muscles.
superficial
The knee is ______ to the thigh.
distal
The heart is ______ to the arm.
medial
The arms are _______ to the chest.
lateral
The collarbone is ____________ between the breastbone and shoulder.
intermediate
The head is ________ to the abdomen.
superior
The heart is _________ to the breastbone.
posterior
The navel is ________ to the chin.
inferior
The breastbone is ________ to the spine.
anterior
Axial consists of
head, neck, and trunk
Appendicular consists of
limbs
Frontal plane
divides body front and back
Median plane(midsagittal)
divides body equally left and right
Transverse plane
divides body superiorly and inferiorly
The cranial cavity encases
the brain
The vertebral cavity encases
the spinal cord
The ventral body cavity consists of what cavities
the thoracic cavity
the abdominopelvic cavity
Membranes in ventral body cavity
parietal serosa
visceral serosa
The parietal serosa…
lines the internal body cavity
The visceral serosa…
covers the internal organs
Pericardium is
heart
Pleurae is
lungs
Peritoneum is
abdominopelvic cavity
Types of energy
kinetic and potential
Chemical energy
stored in bonds of chemical substances
Electrical energy
results from movement of charged particles
Mechanical energy
directly involved in moving matter
Radiant or electromagnetic energy
travels in waves(ex. visible light, UV light)
Muscle and nerve require a lot of ATP so they need a lot of
Oxygen and Glucose
What are the four elements that make up 96.1% of body mass?
Carbon, Hydrogen, Oxygen, and Nitrogen
Atoms are composed of
protons, neutrons, and electrons
Protons and neutrons are found in
the nucleus
Electrons are found in
the electron cloud orbiting the nucleus
What is the atomic number?
the number of protons in the nucleus; written as subscript to left of atomic symbol
What is the mass number?
total number of protons and neutrons in nucleus
What are isotopes?
structural variations of atoms
How do you get the atomic weight?
average mass of numbers of all isotopes of an atom
