Feedback mechanisms
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Feedback mechanisms O Are used to either maintain or amplify (to increase) chemical systems in the body. O Note: To determine the type of mechanism you must be able to determine the stimulus and response.
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Feedback mechanisms. Are used to either maintain or amplify (to increase) chemical systems in the body. Note: To determine the type of mechanism you must be able to determine the stimulus and response. Feedback Mechanisms. Identify a Stimulus and Response. - PowerPoint PPT Presentation
Transcript of Feedback mechanisms
Feedback mechanisms
OAre used to either maintain or amplify (to increase) chemical systems in the body.
O Note: To determine the type of mechanism you must be able to determine the stimulus and response.
Feedback Mechanisms
Identify a Stimulus and Response
Your dog chases the ball and you say “Good Boy!”OStimulus: __________________OResponse:__________________Your dog pees on the rug and you say “Bad Dog!”OStimulus:____________________OResponse:____________________
Feedback Mechanisms
Positive Feedback
Negative Feedback
O The response will increase the stimulus
O Does not return to homeostasis but will cause more of the stimulus to happen.
O The response will decrease the stimulus or return the system back to homeostasis.
Feedback Mechanisms
? ?O The dog pees on
the rug and you say “Bad Dog!”
O Is this Positive or Negative Feedback?
O The dog chases the ball and you say “Good Boy!”
O Is this positive or Negative Feedback?
You have your head phones in listening to your favorite songs.
Positive Feedback Negative Feedback
What would be an example?
O What would be an example?
The Circulatory System
FunctionsO To transport oxygen to the cells of
the body so cells can continue Cell Respiration
O To Transport nutrients to the cells of the body
PartsO HeartO Blood VesselsO Blood
Components of BloodO Red blood cellsO White blood cellsO PlateletsO Plasma
What are Red Blood Cells?
O Also called erythrocytesO Transport oxygenO Contain Hemoglobin
O An iron containing protein that binds to oxygen
O Gives blood a red color
What are White Blood Cells?
O Also called leukocytesO Can live for days, months or even
yearsO Guard against infection, fight
parasites, and attack bacteriaO Can leave the circulatory system and
go into the immune system fighting infection
What are two kinds of White Blood Cells?
O Phagocytes (eating cells)O Engulf and digest bacteria and other
disease causing bacteriaO Lymphocytes
O Produce antibodies that are proteins to help destroy pathogens
What are platelets?O Cell fragments needed for clotting
O Clotting processO Platelet comes in contact with edges of
broken blood vessel and becomes stickyO A cluster of platelets gathers around
the wound forming a clot (scab)
What is plasma?O Fluid part of blood (mostly made of
water)O Straw colored
O Transport fatty acids, hormones and vitamins
O Regulate osmotic pressure and blood volume
O Fight viral and bacterial infectionsO Aid in blood clotting
What are blood vessels?
O Types of blood vesselsO Arteries (largest)O Capillaries (smallest)O Veins
What are arteries?O Large, thick walled blood vesselsO Carry blood from the heart to the
cellsO All arteries except the pulmonary
artery carry oxygen rich blood
What are capillaries?O Tiny blood vessels with walls that are
only one cell thickO Oxygen and nutrient absorption take
place in the capillariesO Also carbon dioxide and waste
products move into the blood through the capillaries
O Diffusion of Oxygen and Carbon Dioxide occurs here in the lungs.
What are veins?O Smaller than arteries but larger than
capillariesO Return blood to the heartO Contain valves to keep blood flowing
towards the heart
Parts of the Heart
Superior Vena Cava
Right Atrium
Right Ventricle
Inferior Vena Cava
Septum
Left Ventricle
Left Atrium
Pulmonary Artery
Pulmonary Vein
Aorta
Blood Flow Through the Heart
O Oxygen poor-1.) Superior and inferior vena cava2.) Right Atrium
3.) Right Ventricle
4.) Lungs
O Oxygen rich-5.) Left Atrium
6.) Left Ventricle
7.) Aorta
8.) Body
Blood Flow Through the Body
O Pulmonary circulationO Right side of the heart pumps blood
from the heart to the lungsO Systemic circulation
O Left side of the heart receives blood from the lungs and pumps it to the rest of the body
Feedback Mechanisms in the Circulatory System
When human tissue, such as skin is torn or cut, all the cells near the damage send out a signal that activates the platelets in that area.A the platelets begin to form a plug, they send out chemical signals calling for more platelets in order to stop the bleeding. Stimulus:__________Response:_________Feedback:_________
Feedback Mechanisms in the Circulatory System
O When muscle cells are active they need more ENERGY (ATP). In cellular respiration, the Mitochondria uses Oxygen to make ATP. After you are done exercising, your breathing returns to a normal rate because the amount of Oxygen required by your cells has decreased.
O Stimulus: ______________O Response:______________O Feedback:_______________
