Patho Exam 1 (negative feedback)

Homeostasis

How the body balances when there is a disturbance

Homeostasis according to Walter Cannon

the ability to maintain stability physiologically and psychologically, during rapid changing conditions in the internal and external environment

Walter Cannon 3 Conditions

Constancy, steady state conditions, regulating systems

Control Systems

regulate cellular functions, regulate physical and psychological adaptation, negative feedback system

Explain Negative Feedback Loop

When something is out of the “normal range” the body releases a substance as a response until the normal range is reached and the response is stopped until the imbalance occurs again

What kind of feedback is a thermostat

negative

Explain glucose negative feedback

Eat sugary food, glucose increases, sensors in Beta cells in Pancreas pick up on increase and release insulin, Glucose takes insulin out of blood and moves it to cells, blood glucose level decreases back to normal, sensor and Beta cells realize no more insulin is needed and stop producing it

Stress (H. Seyle)

state manifested by symptoms that arise from coordinated activation of the neuroendocrine and immune system

What is the general term coined by Seyle for stress

General Adaptation Syndrome (GAS)

Psychoneuroimmunologic Regulations

Stress Response

Hypothalamus stimulates what systems at the same time

endocrine and nervous

Explain the negative feedback of the nervous system

hypothalamus receives stress signal, sends signal to Locus Coeruleus, LC releases norepinephrine, NE triggers Autonomic Nervous System, ANS turns on Sympathetic Nervous System, SNS triggers fight or flight, f/f works medulla of adrenal gland to release more EPI/NE

Explain the negative feedback of the endocrine system

hypothalamus receives stress signal, hypothalamus releases CRF to pituitary gland, works on anterior part of pituitary, pituitary releases ACTH, ACTH works cortex of adrenal gland, adrenal gland releases cortisol, cortisol used for energy needed to exhibit stress response

Which chemical is released by the hypothalamus

CRF (corticotropin release factor)

Which chemical is released by the pituitary gland

ACTH (adrenocorticotropic hormone)

Explain muscle tensing

hypothalamus receives stress signal, releases RNS, simulates spinal cord reflex, muscles tense

What causes muscle tensing

RNS (Reticular Activating System)

term for EPI/NE

chatecolamines

What does vasoconstriction cause

blood flow lessens in the face, causes pale appearance, low blood pressure

Body places functions on back burner for what

Digestion/ kidneys/ immune system/ inflammation response go on back burner to preserve energy so that more energy can be expended to fight stress response

effects of system suppression

dry mouth (digestion) less pee (kidneys) illness (immune/ inflammation)

involved systems

SNS, endocrine, immune, psychoneuroimmunologic regulation