1. Circulatory System Cornell Notes

2. What is blood made of?
Red blood cells contain hemoglobin which carries oxygen (and sometimes carbon dioxide).
White blood cells can destroy many bacteria by engulfing them.
Platelets are sticky fibers that help close wounds.
Plasma is the liquid everything else is carried in.

3. What color is blood? Blood can be different shades of red.
Red blood cells
It is never blue.
In textbooks, blue means “high in carbon dioxide, low in oxygen”
Red means “high in oxygen, low in carbon dioxide”

4. What is the purpose of blood?
Blood vessels act like a highway for the body
Carries carbon dioxide from cells
Carries oxygen to cells
Carries glucose to cells
Carries hormones—
chemicals we will discuss later— to different parts of the body

5. How are arteries and veins different?
Arteries are usually high in oxygen since they carry blood away from the heart
Exception: pulmonary arteries lead into the lungs
Veins are usually high in carbon dioxide since they carry blood toward the heart
Exception: pulmonary veins lead out of the lungs

7. How does blood travel through the heart?
Simple mnemonic device:
Ray’s R.V. went from L.A. to L.V.
Venae Cavae
Right Atrium
Right Ventricle
Left Atrium
Left Ventricle
Aorta

8. Why does blood only move in one direction through the heart?
A system of valves keeps blood flowing in the correct direction.
When blood leaves an atrium, a valve closes like a gate, so blood cannot move backwards.

9. Nervous System Cornell Notes

10. What is the nervous system made of?
The brain, spinal cord, and nerves.
Nerves are bundles of neurons.
A neuron is a long cell.

11. What are the parts of a neuron?
Cell body which contains a nucleus (eukaryote cell)
Many Dendrites receive electrochemical signals called impulses
Axon carries an impulse away from the cell body

12. Axon endings contain neurotransmitter
Myelin sheath keeps the impulse from leaving the cell’s membrane; keeps it moving in the direction toward the axon endings.

13. What is an impulse?
An impulse is a signal started by neurotransmitters
It is like a chain reaction.

14. How does an impulse travel through a neuron?
Dendrite
Axon
Cell body
Axon endings

15. How is an impulse sent to another neuron?
When the impulse reaches the axon endings:
Neurotransmitter is released into synapse
Synapse: space between neurons
Neurotransmitter lands on receptors of nearby dendrites.
How is an impulse sent to another neuron?

16. How do neurons create sensations?
Sensory neurons in eyes/ears/nose/mouth/skin receive an impulse.
The impulse is sent to Interneurons in the Central Nervous System (CNS).
The CNS is made of the brain and spinal cord.

17. How do neurons move our muscles?
Interneurons in our CNS receive an impulse.
The impulse is sent to motor neurons in the Peripheral Nervous System (PNS).
The PNS includes all the nerves that carry messages to/from the CNS
The impulse is sent to a muscle cell (effector).

18. Which neurons are used during thinking?
Choose one of the following:
Sensory neurons
Interneurons
Motor neurons
The correct answer is b.

19. What are the parts of the PNS?
The Somatic Nervous System sends impulses to and from skeletal muscles (neck, arms, fingers, legs, etc.)
The Autonomic Nervous System sends impulses to and from your internal organs (heart, diaphragm, liver, kidneys, etc.)

20. Which neurons are used during a reflex?
a sensory neuron
OUCH! You touch a cactus needle.
A spinal cord interneuron
— NOT a brain interneuron, because you don’t think about what to do next
a motor neuron
You move your hand away quickly.

21. 2.6 Paragraph
The urinary system contains kidneys, which are made of nephrons. Humans have two kidneys. Their job is to filter blood. Each kidney is made of about one million nephrons. A nephron can filter out waste and make sure body fluids are balanced. This describes the role of kidneys and their basic units, nephrons.

22. 4.10 Paragraph
In my study of abused drugs, I learned about stimulants, depressants, narcotics, and hallucinogens. Stimulants increase the activity of the Central Nervous System and the sympathetic .…