nervous system

Question 1

neurons

Answer 1

cells inside the brain, are electrically active chemical factories that carry messages to and from the brain and body, and within our brain

• All the neurons you will ever have are present at birth
• they don’t divide to make new cells
• they grow and make connections within our brains as we age
• the more connections we have, the better

Question 2

glial cells

Answer 2

support and feed the neurons, packed around them

Question 3

macrophage

Answer 3

clears up dead cells and kills germs

Question 4

signals that pass through neurons

Answer 4

they result in our sensations, thoughts, movements, memories, and feelings

Question 5

Neurons are made up of 3 parts:

Answer 5

• the cell body
• dendrites
• axon

Question 6

the cell body

Answer 6

• contains the nucleus, where most of the molecules that the neuron needs to survive and function are made and where neurotransmitters are made

Question 7

neurotransmitters

Answer 7

chemical messengers which help messages travel from neuron to neuron

Question 8

dendrites

Answer 8

extend out from the cell body and recieve messages from other nerve cells (look like branches).

Question 9

Path of signals through the neuron

Answer 9

dendrites –> (through) cell body –> (down) axon (covered in myelin) –> signal stimulates sacs, which release neurotransmitters –> (into) the synapse

Question 10

axon

Answer 10

Gets messages to where they’re needed
messages will travel at different speeds down it. If it has had other cells wrapped around it to form a sheath, then the messages will travel much faster.

Question 11

sheath

Answer 11

made up of a fatty molecule called myelin, which increases speed of transmission
chemical activity only occurs when there’s no fat along the axon, causing it to travel faster

Question 12

synapse

Answer 12

the place where a signal passes from one neuron to the next
- neurotrabsmitters cross it and attatch to a neighboring cell, and the process continues until it reaches where it’s being sent

Question 13

The Nervous System has two systems:

Answer 13

1. Central Nervous System
2. Peripheral Nervous System

Question 14

CNS

Answer 14

• brain + spinal cord
• interprets sensory info to make decisions

Question 15

PNS

Answer 15

• sensory neurons + motor neurons in bundles
• neurons that project between the CNS out of the spinal cord connect the nervous system to the rest of the body