Brain and Biology

Question 1

How many connections do brain cells have between each other?

Answer 1

1000-50 000. They have 160 trillion connections, 86 billion neurons.

Question 2

Definition: form blood-brain barrier, repair and protect by moving toxins, and accelerate transmission.

Answer 2

Glial Cells

Question 3

Description: receive incoming signals, branches spread out.

Answer 3

Dendrites

Question 4

Description: single long fibre, carries outgoing messages.

Answer 4

Axon

Question 5

Description: sustains cell’s life, processes impulses.

Answer 5

Soma (cell body)

Question 6

Description: layer of fatty, whitish cells. Speeds up transmission, impulse jumps from node to node

Answer 6

Myelin sheath

Question 7

What is resting potential?

Answer 7

When the inside of the cell is -70mV more negative than the outside. The cell is ready to fire.

Question 8

What is action potential?

Answer 8

When stimulation makes the membrane more permeable so that more positive ions can enter the cell, causing the inside to reach threshold (-55mV), and then firing.

Question 9

What happens after the cell “fires”?

Answer 9

Depolarization. The positive ions get pumped back out, but too many get pumped out, causing hyper polarization (-80mV). The cell goes into refractory period.

Question 10

What is the process of Synaptic transmission?

Answer 10

1. Impulse reaches terminal button.
2. Neurotransmitters are released into gap.
3. Neurotransmitters attach to receptor site on postsynaptic membrane. Certain NT’s fit in certain receptor (key in lock).

Question 11

Description: Fight or flight. Automatically mobilizes body’s resources. Prepares body for action during emergencies. Examples: dilates pupils, digestion slows down, etc.

Answer 11

Sympathetic Nervous System

Question 12

Description: Rest and digest. Once emergencies are over, brings bodily functions back to normal. Conserves energy while relaxing.

Answer 12

Parasympathetic Nervous System

Question 13

Part of the brain that controls breathing, heart rate

Answer 13

Medulla

Question 14

Part of the brain that connects cerebellum to cortex

Answer 14

Pons (bridge)

Question 15

Part of the brain that regulate arousal; screens incoming messages (attention)

Answer 15

Reticular formation

Question 16

Describe the cerebellum

Answer 16

Has 2 hemispheres.
Balance, posture.
Coordinates motor activity (smooth movements, ex riding a bike)
Predicts sensation (tickling ones self, ex ignoring a feeling on the skin)

Question 17

Part of the brain that takes up the largest area

Answer 17

Forebrain

Question 18

Forebrain structures are:

Answer 18

Thalamus, hypothalamus, limbic system

Question 19

Describe what the Thalamus is used for.

Answer 19

It sits on the brainstem so it can relay incoming messages from sense receptors to the cerebral cortex.

Question 20

Describe what the Hypothalamus does.

Answer 20

"Fighting, fleeing, feeding, fucking"
Monitors eating and drinking, sexual behaviour. 
Biological rhythms and cycles 
Emotional behaviour 
Maintains homeostasis

Question 21

Describe what the Limbic system does.

Answer 21

• Memory and emotion*
• olfactory (smell)
• Includes the hippocampus
• and Amygdala

Question 22

What is the job of the hippocampus?

Answer 22

Formation/creation of new memories, spatial and emotional memories. Remember Henry Molaison.

Question 23

What is the job of the amygdala?

Answer 23

Perception of fear, anger, sadness, controlling aggression. Holds memories involving these emotions and regulates aggression. Ex: if ever bitten by dog, the amygdala may help in processing that event and may increase your fear surrounding dogs.

Question 24

The cerebrum?

Answer 24

Highest mental functions.
Two symmetrical hemispheres:
1. Contralateral (crosses over medulla)
2. Right/Left lateral functions

Has folds (tissues) so it can store more information in the given surface area.

Question 25

What are the 4 regions (lobes) in the hemisphere?

Answer 25

1. occipital (sight)
2. temporal (hearing)
3. frontal (thought and reasoning, personality)
4. parietal (touch)

Question 26

In split brain patients, if they are shown a picture in their right eye, will they remember what they saw?
Left eye?

Answer 26

They will know what they saw if shown through right eye. Will not know if shown through left eye.