Powerpoint 4.1 genetics and evolution of behavior Flashcards
19th century monk Gregor Mendel demonstrated that inheritance occurs through discrete unite of heredity, called..? G….
Genes
Both genes and environment interact to shape..?
H…. B…….
Human behavior
Genes come in pairs called..? A……
And are aligned along…? C……….
Alleles
Chromosomes
-discovered dominant, recessive, research by pea plants, genes….
A gene is defined as a portion of a c……… And is composed of..? …
Chromosome
DNA
DNA serves as a model for the synthesis of…? …
Ribonucleic acid, RNA
RNA is a single strand c……. That can serve as a…? T……./m…. For the synthesis of..? P…….
Is a single strand chemical that can serve as a template/model for the synthesis of proteins
Proteins determine the development of the body by:
- forming part of the s…….. Of the b…
- serving as e……, biological catalysts that regulate chemical reactions in the body
Forming part of the structure of the body
Serving as enzymes
Being homozygous for a gene means that a person has an…?
Identical pair of genes on the two chromosomes
=same
Being heterozygous for a gene means that a person has an…?
Unmatched pair of genes on the two chromosomes
=different
Genes are either d……., R…….., or i………..
Dominant, recessive, or intermediate
-eye color, ability to taste PTC
A dominant gene shows a strong effect in either..?
In either the homozygous or heterozygous condition
A recessive gene shows its effect only in..?
The homozygous condition
Examples such as PTC and hair color can be misleading. it implies that..?
A single g… C………. Completely controls a c………….
A single gene combination completely controls a characteristic, but this isn’t always true
Some genes are only expressed partly:— In some cells and not others
Or only under? C…… C…………
Certain circumstances
Autosomal genes
All other genes except for sex-linked genes
Sex-linked genes
Genes located on the sex chromosomes
In mammals, the sex chromosomes are designated…?
Females?
Males?
X & Y
Females= two X chromosomes (XX)
Males= an X & Y chromosome (XY)
During reproduction females contribute an..?
Males?.. That determines..?
Females contribute an X chromosome
Males contribute either an X or a Y chromosome that determines the sex of the child
If an X chromosome is contributed by the male…?
If a Y chromosome is contributed by the male..?
X= female
Y= male
The human Y chromosome has genes for far fewer …….. Than the X chromosome
Thus, sex-linked genes usually refer to ? Linked genes
Far fewer proteins
Refer to X-linked genes
-example = red-green color deficiency
Sex-limited genes are genes that are present in both..?
But mainly..?
Are genes that are present in both sexes
But mainly have an effect on one sex
-chest hair, breast size
Controlled by other systems, endocrine system, puberty
Genes change in several ways:
Mutation- a heritable change in a…? … Molecule
Microduplication/microdeletion-part of a chromosome that might appear one might appear twice or..?
Heritable change in a DNA molecule
Or not at all
Example= some researchers believe schizophrenia might be a result of microduplications and microdeletions of brain relevant genes
Mono. Means it came from the same..?
Egg
Epigenetics
A field that is concentrated with changes in gene expression without the modification of the … Sequence
The modification of the DNA sequence
- some genes are active only at a certain point in ones life, a certain time of day, etc.
- changes in gene expression are central to learning and memory
- epigenetic differences are a likely explanation for differences between monozygotic “identical” twins
What you do at any moment not only affects you now, but produces e……… Effects that alter gene expressions for a longer period of time
Experiences alter the activity of g…. That we possess
Epigenetic, alter gene expressions for a longer period of time
Genes
Heritability
Refers to how much characteristics depend on g…… Differences
- researchers have found evidence for heritability in almost every behavior they have tested
- heritability of a certain trait is specific to a g…. P………
- strong environmental influences may cause genetic influences to have more/less of an effect
Genetic differences
A given population
Less of an effect
- what’s the likelihood that you have a gene that will be expressed in your lifetime
- no gene found for religion
(Heredity and environment)
Almost all behaviors have both a g…… And an e………… Component.
Researchers:
-study monozygotic and dizygotic twins to infer contributions of h……. And e……….
Study adopted children and their resemblance to their biological parents to infer h……. Influences
-identify specific genes linked to some b…….
Genetic and environmental component
- contributions of heredity and environment
- infer hereditary influences
- behavior
(Environmental modification)
Traits with a strong hereditary influence can be modified by e………… i………..
Environmental intervention
-ex. PKU, a genetic inability to metabolize the amino acid phenylketonuria
-environmental interventions can modify PKU
Don’t eat certain food= no cognitive destruction
-just because you inherit a gene, doesn’t mean you will express it
Environment can affect it
(How genes affect behavior)
Genes do not directly produce b……..
Genes produce p……. That increase the probability that a behavior will develop under certain circumstances
Genes can also have an i……. affect
Behaviors
Proteins
Indirect
-genes can alter your environment by producing behaviors or traits that alter how people in your environment react to you
(The evolution of behavior)
Evolution refers to a change in the frequency of various genes in a p……… Over generations
Evolution attempts to answer two questions:
1) how did….?
2) how do…?
Various genes in a population over generations
- physical and social environments
- regardless of whether the change is helpful of harmful to the species
How did some species evolve?
How do species evolve?
(how did some species evolve?)
How species evolved is based on inferences from f……/c………. Of living species
Fossils/comparisons of living species
(How do species evolve?)
How species evolve rests upon some assumptions:
Offspring generally resemble their parents for g…… R……
Mutations, recombination, and microduplications of genes introduce new h…….. V………
Certain individuals successfully reproduce more/less than others
Genetic reasons
Heritable variations
More than others
(Artificial selection)
Refers to choosing individuals with desired t….. And making them parents of the next g………
According to Darwin, nature also selects, and successful individuals genes will be prevalent in later g……….
Desired traits and making them parents of the next generation
Prevalent in later generations
(Common misconceptions about evolution)
Lamarckian evolution: “the use or disuse of some structure or behavior causes an i……. Or d……. In that behavior”
“Humans have stopped e…….”
“Evolution means i……….?”
“Evolution acts to benefit the i……… Or the s……”
Increase or decrease in that behavior
Humans have stopped evolving
Evolution means improvement
Evolution acts to benefit the individual or the species
(Brain evolution)
One explanation is that our ancestors managed to get enough n…….. To provide a big brain with all the fuel it needs
Managed to get enough nutrition to provide a big brain with all the fuel it needs
- cooking food made it easier to digest
- group hunting was more efficient
- humans have better capacity for glucose transport
(Evolutionary psychology)
Focuses upon functional and evolutionary explanations of how b…….. E……
-assumes that behaviors characteristic of a species have arisen through n…… S…….. And provide a s……. Advantage
Behaviors evolved
Natural selection and provide a survival advantage
Examples: differences in peripheral/color vision, sleep mechanisms in the brain, eating habits, temperature regulation
(Behavior and natural selection)
Some behaviors are more debatable with regard to the influence of n…… Selection
Examples?
Altruistic behaviors?
A behavior that benefits someone other than the a….
Natural selection
- life span length
- gender differences in sexual promiscuity
-altruistic behavior:
A behavior that benefits someone other than the actor
-hard to find outside of humans
(Group and kin selection)
A gene:
- only spreads if individuals with it R…….. More than individuals without it
- that benefits the species but not if the individual dies out with that individual
Group selection:
Controversial hypothesis states that altruistic groups survive better or worse than less cooperative ones
Kin selection:
More plausible. Selection for a gene benefits the individuals R……..
- only spreads if individuals with it reproduce more than individuals without it
- that benefits the species but not the individual dies out with that individual
Group selection:
States that altruistic groups survive better than less cooperative ones
Kin selection:
Selection for a gene benefits the individual’s relatives
(Reciprocal altruism)
The idea that individuals hep those who will R….. The favor
Building a reputation for helpfulness only works if others are willing to c…….. With you
Help those that will return the favor
Others are willing to cooperate with you
