1. The Brain

2. 2 Main Parts:
Cerebrum (conscious)
The rest of the brain (unconscious)

3. (a) Unconscious Brain 1.Medulla Oblongata (Brain stem)… #8 Heartbeat
Respiration rate
Blood pressure regulation
Vomiting, coughing, etc

4. 2. Hypothalamus… #13
Associated with homeostasis
Hunger/thirst
Sleep
Body temperature
Blood pressure
Pituitary gland

5. 3. Thalamus… #5
Relay between spinal cord and brain using the Reticular Activating System (RAS)
Screen sensory impulses

6. 4. Cerebellum… #7
Muscle coordination and balance (inner ear)

7. Cerebrum Basics

8. (b) Conscious Brain (Cerebrum)
Right and left hemispheres
4 surface lobes on each side
Let’s take a look at each lobe…

9. **Label the lobes on both diagrams, if possible!
1. Frontal Lobe…#1
Intellect
Voluntary muscles (skeletal)
2. Parietal Lobe…#4
Sensory (from skin)
3. Temporal
Hearing, smelling, speech
4. Occipital…#6
Vision

10. Left and right hemispheres connected by the CORPUS CALLOSUM… #2

11. Neurotransmitters
Chemicals that communicate info through the brain and body
Relay signals between neurons
Control everything from your heart beat to digestion!

13. Excitatory Neurotransmitters
Initiate impulses in adjacent neurons
Examples: acetylcholine, norepinephrine, epinephrine, dopamine
*They get the neurons firing! (Depolarization sequence)

14. Inhibitory Neurotransmitters
These inhibit the firing of impulses
Can help stop responses such as tremors and seizures
Examples: Serotonin, GABA
A balance of inhibitory and excitatory neurotransmitters in needed for proper brain function!

16. Drug Interactions Nicotine
Shaped like acetylcholine (neurotransmitter)
Binds to receptors, increasing action potentials
Increases dopamine release
- Stimulate muscle movement, breathing, heart rate, learning, and memory

17. Alcohol
Mimics GABA's effect by binding to GABA receptors
Acts as an inhibitor
Simulates endorphins (like GABA and serotonin) as a naturally produced pain killer

18. Marijuana
Chemical produced called THC
Binds to cannabinoid receptors
Affects cerebellum (coordination), cerebral cortex (concentration, perception) and hippocampus (memory, learning)

20. Cocaine
Acts by blocking dopamine transporters (clear dopamine out of the synapse)
Dopamine builds up in synapse
Amplified signal to neurons = feelings of euphoria

22. Fentanyl
Similar to morphine but x more powerful
Belong to Opioid group of drugs (painkillers)
Increases dopamine levels
Dangerous forms are being synthesized in labs  many overdose deaths
Deaths associated with respiratory distress

23. Neuroendocrine Control (Hormones)
Epinephrin (Adrenaline)
Source: Adrenal medulla (central portion of adrenal gland)
Effects: “fight or flight” response
Increased heart rate
Increased [glucose] in blood
Decreased blood flow to digestive tract & skin
Increased breathing rate
Increased circulation to voluntary muscles

24. Control: Secretion of adrenalin by adrenal medulla controlled by hypothalamus
Signal travels via brain stem  spinal cord  sympathetic nerve fibers  adrenal medulla

25. 2. The Pituitary Gland… #12
*Controlled by the
HYPOTHALAMUS

26. Posterior Pituitary
Hormones: ADH, Oxytocin
ADH- results in kidneys retaining water
Oxytocin- causes contraction of the uterus (childbirth) & milk production at mammary glands

28. (b) Anterior Pituitary Hormones: GH- growth hormones (whole body) FSH & LH- teste/ovary development LTH (lactogenic hormone)- develops mammary glands TSH (thyroid stimulating hormone) ACTH- stimulates adrenal gland

29. Negative Feedback Loops
Sensor
Organ
Response
Homeostasis
Stimulus
(internal or external)

30. Example: ADH Release
Stimulus: [water] decreases in blood  low blood volume
Sensor: Hypothalamus
Organ: Pituitary gland (posterior)
Response: Release ADH  effects collecting duct of nephron (in kidneys)
Homeostasis: Retain water  blood volume increases
*Once blood [water] increases, pathway is shut down = self regulatory!!