1. Chapter 3 BIOLOGY AND BEHAVIOR
HOLT Psychology
4/19/2017
Chapter 3 BIOLOGY AND BEHAVIOR
Section 1: The Nervous System
Section 2: The Brain: Our Control Center
Section 3: The Endocrine System
Section 4: Heredity: Our Genetic Background
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2. Chapter 3:Section 1
The Nervous System
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3. Main Objective:
Explain how messages are transmitted by neurons and describe the functions of the peripheral nervous system.
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4. What does the Nervous System do???
Thinking
Feeling
Moving
Dreaming
Regulates internal functions
Learning/memory
Etc….
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5. Consists of 2 main parts:
Central Nervous System:
Brain and spinal cord
2. Peripheral Nervous System:
* made up of nerve cells that send messages between the central nervous system and all the parts of the body.
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6. Neurons: Neurons: A nerve cell; the basic building
block of the nervous system.
Each of us has more than
100 billion neurons!!!
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7. Components of a Neuron:
Cell Body: Produces energy that fuels the activity of the cell.
Dendrites: Receive information from other neurons and pass the message through the cell body
Axon: Carries messages away.
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8. Components of Neuron (cont’d)
Myelin sheath:
A white, fatty substance that
insulates axons and enables rapid
transmission of neural impulses.
Axon terminals:
Small fibers branching out from an axon.
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9. The Communication Process:
Messages are sent from the axon terminals of one neuron to the dendrites of other neurons.
In order for a message to be sent from one neuron to another neuron, it must cross the synapse
A junction between the axon terminals of one neuron and the dendrites of another neuron.
Less than a millionth of an inch wide!
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10. Anatomy of 2 Neurons:
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11. Communication (cont’d)
Messages are received by the dendrites and travel through the cell body and the axon to the axon terminals.
They cross synapses to the dendrites of other neurons
New synapses can develop between neurons that were not previously connected, as when we learn something new!!
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12. Neurotransmitters: Chemical Messengers
Neurons send messages across synapses through the release of neurotransmitters.
Chemicals that are stored in sacs in the axon terminals.
100’s can be fired
every second!!
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13. Neurotransmitters (cont’d)
The message is converted into an electrical impulse that travels the length of the neuron.
The message is then transmitted to the next neuron by neurotransmitters
This whole process takes only a fraction of a second!!!
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14. Different Types of Neurotransmitters!
Acetylcholine (Ach): control of muscles.
Plays a part in Alzheimer’s disease
Dopamine: motor behavior
Deficiency plays a role in Parkinson's disease
Serotonin: emotional arousal and sleep
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15. OVERVIEW OF MESSAGE TRANSMISSION VIA NEURONS
Section 1: The Nervous System
Messages are sent from the axon terminals of one neuron to the dendrites of other neurons
Messages travel in one direction and are received by the dendrites and travel through the cell body and the axon to the axon terminals.
From there messages cross synapses to the dendrites of other neurons.
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16. Hmmm…What do you think???
Endorphins are neurotransmitters that NATURALLY reduce pain and boost mood. Flooding the brain with painkillers, antidepressants, or other drugs may cause the brain to stop producing endorphins. Thus, when such a drug is discontinued, a person may experience a period of discomfort—ranging from mild to agonizing– until the brain resumes production of endorphins. What do you think about antidepressants? Do the benefits outweigh the potential harm?
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17. The Central Nervous System:
Consists of brain and spinal cord
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18. Central Nervous System (cont’d)
Spinal cord:
A column of nerves within the spine that transmit messages to and from the brain.
Protected by the spine.
Spinal reflex: simple, automatic response to something.
EX: Remove hand for hot stove!
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19. Other simple Reflexes:
Blink when dust in your eye
Sneeze with pepper
Tapping on knee to see if kick
Knee-jerk reflex
Want to try?…sit on desk with legs crossed. The “doctor” needs to gently strike the knee with a “karate chop”. Does the knee jerk?
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20. THE PERIPHERAL NERVOUS SYSTEM
Section 1: The Nervous System
Responsible for transmitting messages between the central nervous system and all part of the body and is made up of the somatic and autonomic nervous system
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21. The somatic nervous system transmits sensory messages to the central nervous system.
Activated by touch, pain, changes in temperature, and changes in body position.
Enables us to experience:
Hot/cold; pain/pressure; helps us
maintain posture/balance.
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22. 2 divisions: Sympathetic Parasympathetic
The autonomic nervous system regulates the body’s vital functions such as heartbeat and breathing.
2 divisions:
Sympathetic
Parasympathetic
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23. Sympathetic System:
Activated when a person is going into action, perhaps because of some stressful event.
“Fight-or-Flight”
Prepares you to confront situation or to run away!
May suppress digestion, increase heart & respiration rates, and elevate blood pressure.
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24. Parasympathetic Nervous System:
Restores body’s reserves of energy after an action has occurred.
EX: Heart rate and blood
pressure are normalized,
breathing is slowed, and
digestion returns to normal.
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25. The Brain: Our Control Center
Chapter 3: Section 2
The Brain: Our Control Center
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26. Main Objective:
Identify the major structures of the brain, and explain the functions of each structure.
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27. Brain Divided into 3 Sections:
Hindbrain
Midbrain
Forebrain
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28. Hindbrain: Medulla: Pons: Cerebellum:
Vital functions such as heart rate, blood pressure, and breathing.
Pons:
Located in front of medulla and is
involved in regulating body movement,
attention, sleep, and alertness.
Cerebellum:
Balance and coordination.
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29. The Midbrain: Located between hindbrain and forebrain.
Vision and hearing
Contains part of reticular activating system:
Part of brain that is involved in attention, sleep, and arousal.
EX: Drugs/alcohol can affect
this alertness.
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30. Involved in complex thinking processes!!
The Forebrain:
Involved in complex thinking processes!!
4 key areas:
Thalamus
Hypothalamus
Limbic System
Cerebrum
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31. Thalamus:
The structure of the brain that relays messages from the sense organs to the cerebral cortex.
EX: Relays message to brain, such as pain, in order for brain to respond.
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32. Hypothalamus:
The neural structure located below the thalamus that controls temperature, hunger, thirst, and various aspects of emotion:
Sexual behavior; caring for offspring, aggression; etc….
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33. Limbic System:
A group of neural structures at the base of the cerebral hemispheres that is associated with emotion, motivation, hunger, sex, and aggression.
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34. Cerebrum:
The large mass of the forebrain, consisting of two hemispheres.
Cerebral Cortex:
The bumpy, convoluted surface
of the brain; the body’s control
and information-processing center.
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35. The Cerebral Cortex: What Makes Us Unique
Made up of right and left hemispheres.
Corpus callosum:
The nerve fibers that connect
the left and right hemispheres
of the cerebral cortex.
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36. Information received by one side of the body is transmitted to the OPPOSITE hemisphere of the brain.
Each hemisphere of the
brain is divided into
four parts/lobes.
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37. Complete the following on the SAME handout!
Occipital Lobe:
Vision
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38. Temporal Lobe:
Hearing/Auditory
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39. Parietal Lobe:
Sensory Cortex:
Warmth, cold ,touch ,and pain
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40. Frontal Lobe: Motor cortex
Neurons in the motor cortex fire when we move certain parts of our body.
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41. Association Areas: Association areas:
Areas of the cerebral cortex that are involved in such mental operations as thinking, memory, learning, and problem solving.
Shape information into something meaningful.
EX: Puzzle
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42. Language functions based in left hemisphere
Language Abilities:
Right-handed people:
Language functions based in left hemisphere
About 2 out of 3 left-handed people:
Language in left hemisphere
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43. 2 Key Language Areas: Broca’s Area: Wernicke’s Area:
Located in frontal lobe.
Controls area of face used for speaking.
If damaged, then person speaks slowly,
using simple sentences!
Wernicke’s Area:
Located in temporal lobe
Pieces together sounds and sights
If damaged, then speech becomes meaningless!!
EX: “Stealing cookies”…pg. 63
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44. Left vs. Right Hemispheres:
Left Hemisphere:
Language, logic, problem solving, mathematical computation.
Right Hemisphere:
Imagination, art, feelings, and spatial relations.
Even though have heard “right brained” and “left brained” the hemispheres DO NOT act independently of each other!!
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45. Midsaggital Plane:
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46. Is Phineas Gage Still the Same Man???
Turn to Pg. 65
Is Phineas Gage Still the Same Man???
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47. Methods of Studying the Brain:
Accidents:
Accidents and brain damage
Electrical Stimulation of the Brain:
Stimulate parts of brain to change behavioral patterns.
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48. The Electroencephalogram (EEG):
Electrodes record electrical activity of brain.
Used to diagnose some psychological disorders and locate tumors.
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49. Scans: CAT scan : Computerized axial tomography
3-dimensionanl view of brain.
MRI: Magnetic resonance imaging
More powerful; shows details more clearly
PET scan: Positron emission tomography
Show activity of brain at given time
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50. Chapter 3: Section 3
The Endocrine System
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51. Main Objective:
Explain how hormones secreted by the major glands of the endocrine system affect the body.
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52. Endocrine System:
Consists of glands that secrete substances, called hormones, into the bloodstream.
Chemicals produced by the endocrine glands that regulate specific body functions.
Glands include:
Pituitary gland
Thyroid gland
Adrenal glands
Testes
Ovaries
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53. Pituitary Gland: About the size of a pea.
“Master gland”…VERY IMPORTANT
Stimulated by hypothalamus:
Responsible for the secretion of many different hormones that affect various aspects of behavior.
EX: Growth hormones; Prolactin (stimulates milk on nursing women)
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54. The Thyroid Gland: Produces Thyroxin:
Affects body’s metabolism…its rate of converting food to energy.
Hypothyroidism: Too little thyroxin
Can lead to overweight.
Cretinism: Too little thyroxin in children.
Stunted growth/ mental retardation
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55. The Adrenal Glands: Located above the kidneys Outer layer (cortex):
Secrete cortical steroids, which increase resistance to stress & promote muscle development.
Also, cause liver to release stored sugar,
making energy available for emergencies.
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56. Adrenal Glands (cont’d)
Also produce adrenaline and noradrenalin:
Released when sympathetic nervous system activated.
Help arouse body, enabling
person to cope with stressful
situation.
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57. The Testes and the Ovaries:
(continued)
The Testes and the Ovaries:
Section 3: The Endocrine System
Testes and Ovaries – produce the hormones testosterone, estrogen, and progesterone that play an important role in development, development of primary and secondary sex characteristics and have psychological as well as biological effects.
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58. Testosterone: Male sex hormone. Produced by testes in males.
Small amount in females produced by ovaries.
Produced by testes in males.
Stimulates growth of male
sex organs.
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59. Estrogen and Progesterone:
Female sex hormones produced by ovaries.
Low levels found in men.
Responsible for the following:
Breast enlargement; regulates menstrual cycle; PMS; higher levels of estrogen connected with feelings.
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60. Our Genetic Background
Chapter 3: Section 4
Heredity:
Our Genetic Background
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61. Main Objective:
Explain the role of chromosomes and genes in heredity and evaluate the methods used by psychologists to study the role of heredity in determining traits.
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62. What is Heredity?? Heredity:
The transmission of characteristics from parents to offspring.
Contribute to the following:
Appearance, personality,
psychological disorders
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63. Genes and Chromosomes:
The basic building blocks of heredity.
Traits determined by pairs of genes…one gene in each pair from each parent.
Chromosomes:
Threadlike structures in which genes are found, which are composed of DNA (deoxyribonucleic acid)
Double helix
46 chromosomes with 23 pairs
In pairs…one from mom and
one from dad.
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64. Oh!!! It’s A ????? 23rd pair: Female: Male: Determines sex
2 X-chromosomes
Male:
1 X & 1 Y chromosome
Father determines sex of baby!
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65. Nature vs. Nurture: Nature: Nurture: What people inherit.
Environmental factors
Family, education, culture,
everyday living experiences
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66. What do most psychologists believe??
Believe nature & nurture are equally important!
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67. Kinship Studies: Kinship: 2 Common types: Twin Studies Adoptee Studies
Refers to the degree to which people are related, based on genes.
2 Common types:
Twin Studies
Adoptee Studies
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68. Twin Studies: Identical twins: Fraternal twins:
Differences due to environment (nurture)
More likely to share personality traits & psychological disorders (Ex: autism)
Fraternal twins:
Differences due to genes
AND environment
Share 50% of genes
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69. Adoptee Studies:
If children act more like biological families –then behavior may be largely influenced by heredity!!
Provides ways of sorting
out the effects of nature
and nurture
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70. Twins Reared Apart:
Psychological and personality traits are influenced by heredity.
A way of finding out that
twins reared apart share many
of the same mannerisms despite
their separation
EX: Intelligence, aggression, leadership.
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71. Does Heredity Determine Our Personalities??
Turn to Pg. 73
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72. End of Chapter 3