Nervous System Coordination and Regulation Biozone Check on

Nervous System Coordination and Regulation

Biozone Check on Monday (week 4): 114 – Homeostasis 115 – Maintaining Homeostasis 116 – Negative Feedback 117 – Positive Feedback

Quick Check 1. What roles does the endocrine system play in the body? 2. What is a hormone? Explain how hormones reach the cells where they have their effect. 3. List the glands of the endocrine system. 4. What is the hypothalamus? How does it interact with the pituitary gland?

Answers 1. It regulates long term changes in the body, such as growth and development, and controls many of the body’s daily activities. 2. A hormone is a chemical substance produced by an endocrine gland. Hormones travel through the bloodstream to reach target cells. 3. hypothalamus, pituitary gland, thymus gland, adrenal glands, thyroid gland, pancreas, and ovaries or testes 4. The hypothalamus is an endocrine gland located in the brain. It produces hormones called “releasing hormones” that signal the pituitary gland to release its hormones.

READING (A) Humans are warm blooded animals. This means that we are able to maintain a constant body temperature even when the temperature around us changes. If our body temperature begins to rise, our body responds in several ways to prevent overheating. These responses include sweating which cools the surface of the skin and expansion of the blood vessels close to the surface of the skin to allow for heat loss. Since sweat is largely made of water, our bodies must be properly hydrated in order for sweating to occur.

Think-Pair-Share (A) 1. What internal condition is the body trying to balance or make stable?

Think-Pair-Share (A) 2. Using the information, explain what could happen to a football player’s body temperature if he is not careful to drink while he is training all day in 42 degree weather and why.

Think-Pair-Share (A) 3. What happens to a person’s urine if he/she sweats profusely (a lot) and does not replace this water loss by drinking?

READING (B) Glucose is a simple sugar which our body uses as “fuel” to make energy. Since organisms are constantly using energy, we must maintain a consistent level of glucose in our bloodstream at all times. We get this glucose from our food. After we eat, our food is digested and glucose is absorbed into the blood. This glucose is brought to the cells in the body and is used to make energy. When we have extra glucose in our bloodstream, the excess glucose can be stored in the liver for later use. When needed, this glucose can be released by the liver back into the blood to be delivered to our body cells.

Think-Pair-Share (B) 1. What internal condition is the body trying to balance or make stable?

Think-Pair-Share (B) 2. Using the information, explain how the cells in our body are able to continue to produce the energy they need even toward the end of a fasting day in the month of Ramadan when we haven’t been able to eat or drink from sunrise until sunset?

Think-Pair-Share (B) 3. What is the name of the disease a person has when he/she is not able to maintain normal levels of glucose in his/her body?

READING (C) Our bodies require oxygen in order for our cells to convert the glucose that we eat into energy. When we inhale, we bring oxygen from the atmosphere into our lungs. From our lungs, this oxygen is passed into the blood to be delivered to the rest of our cells. To assure that our cells have enough oxygen, we must maintain a certain level of oxygen in our blood. We can regulate the amount of oxygen in our bloodstream by changing the rate at which we breathe (number of breaths per minute) and how deeply we inhale. The faster we breathe and the deeper we inhale, the more oxygen we take into our lungs and bloodstream.

Think-Pair-Share (C) 1. What internal condition is the body trying to balance or make stable?

Think-Pair-Share (C) 2. Explain how your breathing changes when you travel to places high above sea level. Remember that there is less oxygen in the atmosphere at higher altitudes.

Think-Pair-Share (C) 3. Why does your breathing rate increase when you exercise?

Nervous System – 2 parts: Central Nervous System (CNS): Brain and the spinal cord

Nervous System – 2 parts: Peripheral Nervous System (PNS): Made of peripheral nerves which link the CNS with the body's receptors and effectors.

Word Work! Periphery outside the boundary of something. Peripheral nerves reside outside the CNS

Divisions

Stimulus A Neuron Transmits signals to other nerve cells Cell body Axon Conducts signals down the axon Neuron receives a Dendrites signal Nerve endings

Action Potentials An action potential is a wave of chemical and electrical change that moves through the membrane. Neuron 1 Neuron 2

Neurons 1. Sensory (afferent) Neurons: Receptor to CNS 2. Relay Neurons: Within the CNS (aka interneurons or connector neurons) 3. Motor (efferent) Neurons: CNS to Effectors

Receptors to Effectors

Sense Organs Sense organs contain groups of receptors that respond to specific stimuli.

Stimulus-Response Model Remember: R SIME R S I Interneuron E M

Pause and Think What is going on with the nervous system when you are driving and you see a red light?

Reflex – A Simpler Pathway! A reflex is a rapid and involuntary response to a stimulus.

Reflex Tests

Classwork REVIEW BOOKLET – Homeostasis Feedback Receptors and Variables Nervous System Endocrine System

Edrolo Homework AOS 2 – Survival through Adaptations and Regulations https: //edrolo. com. au/s/16448/ Adaptations https: //edrolo. com. au/s/16449/ Biomimicry https: //edrolo. com. au/s/16450/ Regulation DUE ON MONDAY!