People almost universally like sweet things (nothing in nature is sweet AND poisonous)

Sometimes there are traits like agression that can be explained (partially) because it was favorable for survival in the past [ but now may be maladaptive] —> they dont make our lives better

Genetics basics -

• Chromosomes - [Genes] 46 (23 from mom and 23 from dad)

• Dna - genetic information

• Genes - small segments of your chromosomes

• Genomes - instructions for making an organism

Genetics

• Heritability : the proportion of varation among individuals that we can attribute to genes

• Interaction: the effect of one factor (such as enviorment) Depends on another factor such as heredity

  • Our GENES affect how people react to things and influence us

  • Enviorment : every nongenetic influence, from prenatal nutrition to the people and things around us

  • ( which of our genes get activated is influence by our enviorment)

Epigenetics

—> the study of how an enviorment can alter genetics

• Providing a highly stimulating enviorment (High lick mother rats vs low lick mother rats) for rats as they develop generates improved memory capacity

• BUT it ALSO creates improved memory capacity for their babies (AT BIRTH)

Genes and Twins

• differences between identical (monozygotic) vs. Fraternal (dizygotic)

• monozygotic -

• dizygotic -

  • genetically identical twins are more likely to…

    • be affected by same disorders

    • behavioral similarities

    • look alike

Mind Map: Differences Between Identical and Fraternal Twins

Central Idea

• Twin Types: Identical vs. Fraternal

Main Branches

1. Genetic Makeup

• Identical Twins

  • Originates from a single fertilized egg

  • 100% genetic similarity

• Fraternal Twins

  • Develop from two separate eggs fertilized by two different sperm

  • About 50% genetic similarity

2. Physical Appearance

• Identical Twins

  • Often look very similar

  • Same sex

  • May have identical fingerprints

• Fraternal Twins

  • Can look different or similar

  • Can be of different sexes

  • Unique physical traits

3. Psychological Traits

• Identical Twins

  • Higher likelihood of similar personality traits

  • Shared experiences may enhance similarities

• Fraternal Twins

  • More variation in personality and behavior

  • Individual experiences can lead to distinct traits

4. Birth Rates

• Identical Twins

  • Occurs at a consistent rate (about 3-4 per 1,000 births)

• Fraternal Twins

  • More common, influenced by factors like maternal age and genetics

5. Health Considerations

• Identical Twins

  • Higher risk for certain genetic disorders

  • Shared placental conditions can affect health

• Fraternal Twins

  • Individual health risks based on separate genetic backgrounds

6. Social Dynamics

• Identical Twins

  • Often have a close bond and shared identity

  • May face challenges in individuality

• Fraternal Twins

  • Can develop distinct identities

  • Different interests and social circles

Twins studies - IQ TEST SCORE

— identical raised togheter (most similar)

— identical raised apart (second most similar)

— fraternal raised togheter (third most similar)

— fraternal raised apart ( least similar)

Adoption studies

• Genes matter

  • adopted children are more similar to their biological parents than their adoptive parents

    • especially in personality

• parents do have an influence on various views and belief, such as personal values, manners, faith, and politics

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NERVOUS SYSTEMS

Central nervous system

• brain and spinal cord

  • spinal cord connects brain with peripheral nervous system

  • Desision making portion of our Nervous System

Peripheral nervous system

• Everything else

  • motor and sensory neurons that recieve info and transmit CNS decisions

• 2 parts

  • somatic nervous system (voluntary control of skeletal muscles

  • Autonomic Nervous System: controls functions of glands & internal organ muscles (Happens automatically!)

• the autonomic nervous system is further divided into two parts:

  • Sympathetic Nervous System

  → arouses energy

  → Dilates pupils, speeds breathing and heart rate, relaxes bladder

  → “Fight or flight”

  • Parasympathetic nervous system

  → calms you down

  → Slows breathing and heart rate, increases digestion

  → “Rest and digest”