What factors influence behavior? How does evolution influence behavior? Explain examples of learned...

• What factors infl uence behavior?• How does evolution infl uence behavior?• Explain examples of learned vs. innate

behaviors?

NERVOUS SYSTEM AND ANIMAL

BEHAVIOR

Compare and contrast Bird brains and human brains

The nervous system receives and interprets signals

Neurons – specialized cells that receive and respond to stimuli

Nerves – bundles of neurons

THE NERVOUS SYSTEM

THE NERVOUS SYSTEM

3 categories of neurons:1. Sensory neurons

carry information to the CNS

2. Motor neurons carry information away from CNS toward eff ector tissue

3. Interneurons are located between sensory and motor neurons

THE NERVOUS SYSTEM

Sensory receptors – detect sensory input• These are neurons or other

cells that communicate with sensory neurons

• They detect changes in conditions inside or outside the body

The spinal cord also is a refl ex center

Refl exes – automatic responses to stimuli

Refl ex arc – prewired circuit of neurons Sensory neuron receiving stimulus Interneuron transmitting

information Motor neuron sending message to

muscle Refl exes allow a person to react

quickly to dangerous stimuli

Withdrawal refl ex – when touching something hot The pain stimulus travels from the spinal cord to

the brain and takes a little longer than the refl ex

You have removed your hand from the heat before you feel the pain

The brain is where decisions are reached and bodily activities are directed and coordinated

The human brain is roughly the size of a small cantaloupe

21.2 THE BRAIN

The brain is housed in the skull and sits inside a liquid bath called the cerebrospinal fluid for protection and cushioning

THE BRAIN

Largest part of brainContains many folds and bumps

Sulci vs. gyriCorpus callosum is found b/t the L

and R Responsible for reasoning,

intellectual fxn and critical thinking

CEREBRUM

CEREBELLUM

Regulates balancebody positionPostureMuscle coordination

MidbrainPonsMedulla oblongata

BRAIN STEM

MEDULLA OBLONGATA

Vital Reflex center

Visceral activities: blood pressure, respiratory

cardiac

Part of the brain stem

Injuries often fatal

PONS

b/t midbrain and medulla oblongata

Regulates rate and depth of breathing

Homeostatic mechanisms

1. The temporal lobe involved in auditory and some visual information; memory and emotion

2. Occipital lobe processes visual information from eyes…

3. Parietal lobe processes information from touch; self-awareness

4. Frontal lobe processes involuntary muscle movements; planning and organizing future expressive behavior

CEREBRUM There are 2 hemispheres, each divided into 4 lobes

Cerebral cortex – wrinkled outer surface

If unfolded, a human cerebral cortex would be the size of a 16’ pizza Lots of surface area in a

small space Fissure – deep groove

dividing the cerebrum and cortex Divided into right and left

cerebral hemispheres

Corpus callosum – bundle of nerve fi bers at base of fi ssure – l inking two hemispheres

Functions of the brain are divided between the right and left hemispheres The left hemisphere

controls the right half of the body

The right hemisphere controls the left half of the body

The left hemisphere controls speech, reading and abil ity to solve mathematical problems

The right hemisphere controls spatial abil ity and musical and artistic creation

THE BRAIN

1. Medulla oblongata located here.2. Regulates balance3. Cerebral cortex is located here4. Capacity for intellectual function resides here5. Breathing rate is regulated here6. Has folded layers with bumps and grooves7. Regulates posture8. Contains the corpus collosum9. Pons located here10. Leads to spinal cord

CEREBELLUM, CEREBRUM, OR BRAIN STEM

Neurons are highly specialized cells that usually don’t divide

Damage to neurons can’t be repaired by cell division – many times results in permanent impairment

NEURON STRUCTURE

DendritesSomaAxon terminalsAxon

Many neurons have axons covered in a protective layer – myelin sheath – that insulates to prevent sideways transmission Increases speed of

transmission (100x) composed mainly of

lipids and is white like animal fat

Nervous tissue of myelinated cells is called white matter

NEURON STRUCTURE

Gray matter are unmyelinated neurons

Transmit impulses slower

NEURON STRUCTURE

•Potassium channels are ‘leaky’ and allow potassium to passively move to the outside•The sodium-potassium pump in the neuron membrane moves sodium out and potassium in•Using ATP, the sodium-potassium pump moves 3 Na+ out for every 2 K+ in•This restores the potassium levels in the cell

•The depolarization – loss of charge difference – moves in a wave down the cell

Repolarization – when potassium ions leave and internal cel l state is more negative than outside

After traveling along the axon, the signal must be passed along to the next neuronMost neurons are not physically connected

Synapse – the gap between two neurons

SYNAPTIC TRANSMISSION

COMMUNICATION BETWEEN NEURONS, OR MUSCLES, OR GLANDS

ANIMATIONS OF SYNAPTIC TRANSMISSION

http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter10/animation__function_of_the_neuromuscular_junction__quiz_3_.html

What would occur if the neurotransmitter stayed in the synapse? After the neurotransmitter

causes the response Removed from synapse Enzymes break down

neurotransmitters Reuptake – some

neurotransmitters are reabsorbed by the presynaptic neuron

By enzymatical ly breaking down and reuptake of neurotransmitters, there is no continuous st imulation of the postsynaptic cel l

SYNAPTIC TRANSMISSION

http://science.education.nih.gov/supplements/nih2/addiction/default.htm

Chemicals that are released from one neuron at the presynaptic nerve terminal. Neurotransmitters then cross the synapse where they may be accepted by the next neuron at a specialized site called a receptor.

NEUROTRANSMITTERS

Released from brain and ANS Adrenal gland

ExcitatorySense of feeling goodMonoamineCan be used to manage hypertension

NOREPINEPHRINEAKA: ADRENALIN

DOPAMINE

Released from brain (CNS) hypothalamus

Receptors: heart, kidneys, bld vessels

Inhibitorysense of feeling goodParkinson’s Diseaseamine

SEROTONIN

Brain (CNS)Regulates endocrine

activity (hormonal controls)

Leads to sleepinessControls sleep/wake cycles

amineInadequate amounts:

Severe depression and obsessive/compulsive disorders, anger issues, and eating disorders

NeuropeptideProduced in brain (CNS)Pain relief: inhibitoryReleased in times of pain or stressElevated levels cause disease known as Addison’s

diseaseStructure is similar to???

morphine

ENDORPHINS

Depression is a diseaseFeelings of helplessness and despair and thoughts of suicide

It may involve three neurotransmittersSerotonin & dopamine (inhibitory) and norepinephrine (excitatory)

NEUROTRANSMISSION, ALZHEIMER’S, DEPRESSION, PARKINSON’S, AND ADD

Parkinson’s disease is a malfunctioning of neurons that produce dopamine, causing nerve cells to fire without regulation Tremors, rigidity and

slowed movements

ADD may be due to abnormal levels of dopamine

Dopamine controls emotions as well as complex movements

May be due to overabundance of dopamine receptors on presynaptic cells – too much reuptake

NEUROTRANSMISSION, ALZHEIMER’S, DEPRESSION, PARKINSON’S, AND ADD

Ritalin is thought to increase dopamine’s abil ity to stimulate postsynaptic cells Block reuptake receptors in

presynaptic cells Dopamine in synapse longer

Stimulants in high doses result in Euphoric feeling More energy and endurance Sense of power Feeling of mental sharpness

After the stimulants wear off , user feels Heightened fatigue Insomnia Poor concentration Irritability Tearfulness Depression

RITALIN®

DRUGS ALTER CHEMISTRY IN THE BRAIN….ALTERING BEHAVIOR!

https://www.youtube.com/watch?v=90cj4NX87Yk

LABEL THE NEURON BELOWMYELIN, NUCLEUS, DENDRITE, AXON TERMINAL, SHWANN CELL , SOMA,

NODES OF RANVIER

1

5

43

26

7

SENSORY STRUCTURES

ACCOMMODATION

TAPETUM LUCIDUM

ComponentsBehavior: an action that

an individual carries out in a response to a stimulus

Stimulus: action or agent that changes activity of an organism

Response: biological reaction resulting from a stimulus

Examples Noise startlesBacterial produce an

immune response

ANIMAL BEHAVIOR

ANIMAL BEHAVIORS

Behavioral Cycles(responds to natural cycles )

Social Behavior(Interactions with others thru)

Competition And

Aggression

Communication(Depends on senses)

SeasonalEx: Migration

DailyEx: Circadian rhythms

1. Courtship2. Building

homes3. Hunting4. Protection5. Fighting

rivals

Claim or protect territory

1. Visual signals

2. Chemical signals

3. Sound4. language

Survival strategies1. Foraging:2. Anti-predator behavior3. Cyclic behavior (seasoning, circadian rhythms)

How does nocturnal behavior benefit some animals but not others?

Modes of Communication1. Signals help influence behavior of animals

(chemicals, tough, sound, language)

Reproductive Strategies Social Territorial Courtship (sexual selection, competition) Prenatal care Cooperative behaviors

CLASSES OF BEHAVIOR

HOW DOES THE BODY RESPOND?

Sensory systems gather information about the environment

The info will trigger responses to the nervous system which a produces a response

INFLUENCES ON BEHAVIOR( INTERNAL VS. EXTERNAL)

Genes (Nature)

May increase the likelihood that an organism will display a behavior

Tongue rolling, nocturnal activity, aggressiveness

Environment (Nurture)

Helps to determine what traits are displayed

Natural selection

Traits are favored that increase an individual’s reproductive success.

Over time, those beneficial traits become more and more common in the population

Lions

Male lions will kill all lion cubs after taking over a tribe.

Why?

EVOLUTION OF BEHAVIOR

Natural selection favors traits that increase an organisms reproductive success.

EVOLUTION OF BEHAVIOR

Innate behavior

Fixed action patterns Triggered by a

stimulus in the environment and do not stop once the behavior has begun.

Learned behavior

Habituation An animal learns to

no longer respond to a frequent harmless or unimportant stimulus

Reasoning Problem solving

Classical Condition

Operant conditioning

ASSOCIATIVE LEARNING

ImprintingOccurs when an animal develops a particular response to an object or organism only during a brief period early in life.

What are the benefits of imprinting?

SENSITIVE PERIODS

Foraging Behavior

CLASSES OF BEHAVIOR: SURVIVOR

Woodpecker https://www.youtube.com/watch?v=wugUc0fi54k

FORAGING

https://www.youtube.com/watch?v=RamV-AjID8E

ANTI-PREDATORY BEHAVIOR

Sight

CLASSES OF BEHAVIOR: COMMUNICATION

CUCKOO BEHAVIOR

European cuckoos exhibit brood parasitism Female lays eggs in a nest

of another bird Once the eggs hatch, it

reacts to any other object in the nest by pushing it out…thus it receives all the parental care from the surrogate parents

Soon, it becomes larger than the parent that is trying to fee it.

Please answer questions on ½ y.o.p.

1. What is the fundamental unit of the Nervous System?

2. What part of the brain is responsible for motor coordination and balance?

3. What part of the brain controls vital organs? (like breathing rate/depth)

4. Describe how do neurons communicate with each other?

5. What are the two categories of animal behaviors?

6. Discuss how behaviors are influenced?

REVIEW QUESTIONS