Homeostasis

Homeostasis Have you ever been running on a hot day and started sweating? Or out in the snow and started to shiver?

Homeostasis Sensor Stress (Stimulus) Skin Control Center Heat from sun Homeostasis is the ability to maintain a relatively stable internal condition even though the outside world consist of a changing environment. There are three components to the homeostatic system: The Sensor which detects the stress. The Control Center which receives information from the sensor and sends a message to the Effector. The Effector which receives the message from the control center and produces the response which reestablishes homeostasis. Sensor Stress (Stimulus) Skin Control Center Heat from sun Brain Hypothalamus Effect (Response) Effector Sweat cools off body Sweat Glands

Why don’t you keep sweating???? Heat receptors in the skin Hypothalamus Hyperthermia Stress (Stimulus) Control Center Sensors The Effect reduces the Stress and shuts down the mechanism Increased activity of sweat glands Perspiration evaporates cooling the skin Increased blood flow to the skin Effect (Response) Effectors

Negative Feedback Loop A negative feedback loop is homestatic pathway where the response of the reaction shuts down the stimulus and therefore stops the response.

Positive Feedback Loop In a Positive Feedback Loop the response increases and accelerates the stress (stimulus). Can anyone come up with an example of when the body does this? Stress (Stimulus) Sensor Control Center Intensifies Effect (Response) Effector

Positive Feedback - Childbirth Control Center Effector Effect (Response) Stress (Stimulus) The birth of the child will bring this process to a close. Other examples of positive feedback regulation occur during milk letdown and blood clotting. Sensor

Two pathways the Feedback Loops Use Neural Pathway NERVOUS SYSTEM Hormonal Pathway ENDOCRINE SYSTEM Function: Monitor and control responses to internal and external stimuli. Characteristics: Can work independently or together to maintain homeostasis.

ORGANS NERVOUS SYSTEM ENDOCRINE SYSTEM Brain Spinal Cord Nerves

CELL UNIT Neuron Specialized cells in glands NERVOUS SYSTEM ENDOCRINE SYSTEM Neuron Specialized cells in glands

CHEMICAL MESSENGERS Neurotransmitters Hormones NERVOUS SYSTEM ENDOCRINE SYSTEM Neurotransmitters Hormones

SPECIALIZED COMMUNICATIONS PATHWAYS NERVOUS SYSTEM ENDOCRINE SYSTEM Reflex arc Senses Negative and Positive Feedback Loops Negative and Positive Feedback Loops

RATE OF REACTION Hundredths of a second Seconds, Minutes, Hours,Days NERVOUS SYSTEM ENDOCRINE SYSTEM Hundredths of a second Seconds, Minutes, Hours,Days

How does Caffeine Affect Carlos came to school in the morning after staying up until 4 AM playing Call of Duty. He felt tired and sleepy and he was worried because he had a test in English class. Carlos could not understand how his friends could stay up all night playing Call of Duty and then coming to school and staying awake. His friend Jose advised him to buy a Cappuccino at the Conquest Coffee store; he told him it would give him a quick boost of energy. “Coffee keeps me moving, I need a t least one cup in the morning one in the afternoon and a Monster thought out the day, “said Jose. “It allows me to stay awake in class and get good grades; however, I have noticed that I also get sick more often.” Carlos took Jose’s advice and drank two cappuccinos and one Monster. During the day Carlos felt jittery, his hands were shaking and he could not sit still. He felt his heart beating faster and felt energized. He also felt that he needed to use the restroom more than usual. His friend Sylvia asked him if he was feeling ok, because he looked anxious. At the end of the day rather than waiting for his ride, Carlos felt he had enough energy to run home. At dinner, his mom noticed his hands were shaking. She asked if he felt all right. Carlos explained that he felt over stimulated.

List common foods and drinks that contain caffeine. Coffee 150 ml (5 oz) 60-150 Coffee, decaf 2-5 Tea 40-80 Hot Cocoa 1-8 Chocolate Milk 225 ml 2-7 Jolt Cola 12 oz 100 Josta 58 Mountain Dew 55 Surge 51 Tab 47 Diet Coca Cola 45 Coca Cola 64 Coca Cola Classic 23 46 RC Cola 34 Dr. Pepper 61 Mello Yellow 35 Mr. Pibb 27 Pepsi Cola 43 Cherry Coca-Cola 8 oz 7-Up Mug Root Beer Sprite Ben/Jerry No Fat Coffee Fudge Froz. Yog. 85 Starbucks Coffee Ice Cream 40-60 Dannon Coffee Yogurt 45 Chocolate Bar 3-63 Chunky Bar 11.6 100 Grand Bar 11.2 Nestle Crunch Bar 10 Krackel Bar 8.5 Peanut Butter Cup 5.6 Kit Kat Bar 5 Mr. Goodbar Raisinets 2.5 Butterfinger Bar 2.4 Baby Ruth Bar Special Dark Sweet Chocolate Bar 31 Chocolate Brownie 8 Chocolate Chip Cookie 3-5 Chocolate Ice Cream 2-5 Milk Chocolate 1-15 Bittersweet Chocolate 5-35 2 After Eight Mint 1.6 Jell-O Pudding Pop Chocolate

What parts of the body does caffeine affect?

How were these body parts affected?

What actually happened?.