Nervous System Basics
The two main parts of the nervous system are____?
CNS and PNS
A sudden, automatic response to a stimulus.
Reflex action
Chemical messengers that travel in the blood to target organs are called:
Name one system that works with the nervous system to maintain homeostasis.
Endocrine system
Did you know? Your brain is about 2% of your body weight but uses 20% of your energy. What organ is this?
BRAIN
This part of the nervous system controls voluntary actions and conscious thought.
Central Nervous System (CNS)
Which is an example of a reflex action?
A. Writing your name
B. Pulling hand from fire
C. Dancing
D. Reading
B. Pulling hand from fire
Name the “master gland” of the endocrine system.
During stress, which hormone is released by the adrenal glands?
Adrenaline
Some animals release hormones to survive winter by hibernating. Which type of hormone controls this?
MELATONIN
Which of the following is an example of the nervous system maintaining homeostasis?
A. Sweating when hot C. Storing fat
B. Digesting food D. Producing antibodies
A. Sweating when hot
Why are reflex actions important?
A. They are slower
B. Protect the body from harm
C. Increase hormone production
D. Control growth
B. Protect the body from harm
These hormones regulate blood sugar:
A. Insulin and glucagon
B. Adrenaline and thyroxine
C. Cortisol and melatonin
D. Testosterone and estrogen
A. Insulin and glucagon
Shivering occurs when the body is cold to maintain body temperature. Which mechanism is this an example of?
HOMEOSTASIS
A person’s body produces more thyroxine than normal. They feel nervous, lose weight, and have rapid heartbeat. This is called:
Hyperthyroidism
Why is the nervous system faster than the endocrine system?
Uses electrical impulses
Compare a reflex action to a voluntary action.
A. Reflex is slower than voluntary
B. Reflex is involuntary, voluntary is conscious
C. Voluntary is automatic
D. Reflex does not protect the body
B. Reflex is involuntary, voluntary is conscious
Which hormone controls metabolism?
Blood glucose rises after a meal, triggering insulin release to lower it. This is an example of which type of regulation?
NEGATIVE FEEDBACK MECHANISM
Your heart rate, breathing, and digestion are partly controlled automatically without thinking. What system controls these?
AUTONOMIC NERVOUS SYSTEM
Predict what would happen if the CNS was damaged in a region controlling the legs.
PARALYSIS
A patient cannot regulate temperature, thirst, or hunger, yet all endocrine glands are intact. Which organ/system is damaged?
Hypothalamus
A patient has low calcium levels, leading to muscle spasms and tingling sensations. The hormone that regulates calcium is deficient.
PARATHYROID HORMONES
A patient with diabetes cannot regulate blood glucose. Which two systems normally work together to maintain glucose homeostasis?
Answer: Endocrine – Nervous
The fastest nerve impulses in your body travel at about:
120 m/s