Bellwork 12-9-14Answer on a sheet of notebook paper!

• Which organ system exchanges oxygen and carbon dioxide between the body and the external environment?

A muscular

B immune

C digestive

D respiratory

Need to Know

• Explain one benefit and one harmful effect of inflammation in our bodies’ organ systems. Use complete sentences and cite evidence from the text to explain your answer.

Objectives

• Explain the basic functions of a major organ system. (SPI0707.1.3)

42. Nervous and Endocrine Systems (one page)

Nervous System (pg. 282-295)

• The nervous system acts as the body’s central command post.

• Two basic functions:1. Gather and interpret information from inside your

body and from the world outside.

2. Respond to that information as needed.

• Two parts of the nervous system:1. Central nervous system (CNS)- brain and spinal cord

2. Peripheral nervous system (PNS)- connects all parts of the body to the CNS and uses nerves to carry information between your body and the CNS.

Nervous System (pg. 282-295)

Peripheral Nervous System:• Messages about your environment travel through the

nervous system along neurons.• A neuron is a nerve cell that is specialized to transfer

messages in the form of fast-moving electrical energy or impulses.

Nervous System (pg. 282-295)

Peripheral Nervous System:

• A nerve is a collection of nerve fibers (axons) through which impulses travel between the CNS and the other parts of the body.

A message from the brain travels down the spinal cord, then along the axon of a motor neuron inside a nerve to the muscle. The message makes the muscle contract.

Nervous System (pg. 282-295)Central Nervous System:• The brain is the mass of nerve tissue that is the

main control center of the nervous system.• Three main parts of the brain:

1. Cerebrum- largest part of the brain where you think and where most memories are stored; controls voluntary movements and allows you to sense touch, light, sound, etc.

2. Cerebellum- second largest part of the brain that allows the brain to keep track of your body’s position, such as balance.

3. Medulla- connects to your spinal cord and controls involuntary processes, such as blood pressure and heart rate.

Nervous System (pg. 282-295)

Central Nervous System:

• The spinal cord carries information to and from the brain.

• Vertebrae protect the spinal cord.

• BrainPop- Nervous

Endocrine System (pg. 296-299)• The endocrine system is a collection of glands and groups of cells

that secrete hormones that regulate growth, development, and homeostasis.

• A gland is a group of cells that make special chemicals for the body.• A hormone is a chemical messenger that flows through the

bloodstream to all parts of the body. • Epinephrine (adrenaline) is released from the adrenal gland, which

increases your heartbeat and breathing rate.• When you are frightened, angry, or excited, this “fight-or-flight”

response prepares you to fight the danger or run from it.

• BrainPop- Endocrine

Drawings

• For each body system, draw and color at least one organ that belongs in that body system.

• For example:– Nervous System= brain, spinal cord, nerves– Endocrine System = the different glands

• Use your textbook pictures or the sample sheet in the folder at your group.

Human Body Books

Interesting FactsNervous System:• Male canaries sing a new song

every year. Male canaries replace old brain cells related to song production with new neurons each spring. In the spring, the brain-cell clusters associated with vocalization grow larger. So, males compose their new melodies and females learn to recognize the males by their new songs.

• Long-term memory enables us to recall events that happened to us long ago. These memories can be triggered by a stimulus, such as a song or a smell, or they can be deliberately recalled. Recalling memories helps us to refresh them and makes them last a lifetime.

• Fainting is often caused by suddenly low blood pressure and insufficient blood flow to the cerebrum.

Endocrine System:• Epinephrine occurs naturally in

the body, but it is also administered as a drug by doctors. It can be injected into the heart to help revive a person who has suffered from a heart attack.

• The pancreas makes two different hormones, insulin and glucagon. If the pancreas does not make enough insulin, the person will have a condition called diabetes.

• Another hormone imbalance is when a child’s pituitary gland doesn’t make enough growth hormone.