Chapter 2

What can influence behavior through the control of the development of the physical structures that detect and respond to the stimulus causing the behavior?

GENES

True/false: there is a genetic disposition and an environmental factor that will influence the genes causing behavior

True

True/false: there is An environmental factor that influence causing behavior, but not genetic disposition

False

Behavioral genetics

Looks at how genes influence behavior

Genes are made up of

DNA, deoxyribonucleic acid

Purine

Adenine and guanine

Pyrimidines

Cytosine And thymine/uracil

Codon

A sequence of three nitrogenous Bases/nucleotides

DNA is found in the

Nucleus, mitochondria

_DNA is involved in the genetic determination of behavior

Nuclear

Nuclear DNA is stored in_which include includes DNA, Histone proteins, and RNA

Chromatin

Transcription

In transcription a copy of the DNA molecule is created called a messenger RNA. Unlike DNARNA is single-stranded molecules so only one of the two DNA strands copied the mRNA molecule will carry the genetic code out of the cell nucleus into the cytoplasm for the next step.

Translation

The genetic code is converted into amino acid code. The genetic code is broken up into units of three basis called codon and or triplets. The code will cover for a specific amino acid. This involves the use of ribosomes to link the amino acid to form peptides.

Alleles

More than one version of each gene

Most animals are_ Or having two versions of GENES

Diploid

Behavioral genetics holds that_is a function of which genes are being expressed

Behavior

Regulatory gene, influencing expression of other genes by producing

Transcription factors

A particular animal behavior is typically the result

Of many genes interacting with one another and the environment

The heritability of a particular behavior and a specific population is the ratio of the variation caused by the genetic differences in the total amount of variability and that behavior within the population it ranges from zero to one where the closer of the value is to one the

Greater the variation is due to genetics

The ratio of the variation value for a complex trait is usually below

0.5

Genomics

The study of an organism’s entire DNA genome by utilizing gene sequencing techniques to cut out all of your genes within a species DNA

Functional genomics

Tries to determine the function of an individual genes

Comparative Genomic

Studies differences in the genomes between species

What are different methods of studying behavioral genetics?

The use of inbreeding, the use of artificial selection, using induced mutations to scream for behavioral changes, the use of natural, genetic variance, the use of candidate genes, and sometimes will work at the protein level

Principles of behavioral genetics

One gene can have multiple effects, gene form And interacting networks can influence more than one behavior

One GENES can have multiple effects

Typically one Gene will affect the expression of two or more loosely related behaviors

GENES form interacting that network that influence more than one behavior

a gene that causes one behavioral effect may also ionfluence the degree of expression of another gene producing behavior. this can cause a cascading effect

Social recognition between female mice in a Formation of social bonds required to interaction of protein, products of four GENES

Estrogen receptor alpha, estrogen receptor beta, oxytocin receptor, and oxytocin. estrogen and oxytocin are hormones

Cells that response to specific hormone must have the appropriate

Receptor proteins

How genes can affect behavioral variation?

how animals behave, but behavior isn’t caused by just one gene. Multiple genes can work together to influence how animals act. These behaviors aren’t always fixed patterns (like FAPs); they can vary based on genetic differences.

there are a few causes for the genetic basis of behavioral variability: Meadow VOLES versus Prairie VOLES

Meadow are non-monogamous while prairie are monogamous. Both respond to a genetic product, the hormone phase of present. This is due to differences in the distribution of vasopressin receptors in their brains. Males have a much higher number of vasopressin receptors, and they are much concentrated in the pleasure center of the brain. After mating, vasopressin floods, the receptor regions in the brain of the prairie stimulating the reward response. The male associates, the smell of the female with response from his pleasure center and a pair bond forms

Since male Meadow VOLES lack the density of Vasopressin receptors, and do not have many in their pleasure center,

They do not get the reward response. They do not associate the center of the female with the reward response and a pair bond do not form.

generally, a behavior would be a combination of

genetic and environmental influences

Case study: dominance behavior in the Cichlid fish Astro tilapia BURTONI

These males come into 2 adult forms: dominant males are brightly colored aggressively, territorial, and having a high degree of reproductive success. Subordinate males are cryptically colored, not territorial and have a low level of reproductive success.

What is the difference between the dominant A. BURTONI versus subordinate males

DOMINANT MALES HAVE A HIGHER GONADOTROPIN releasing factor, GNRF GENE.

The activity level of the GNRS is affected by

social stimuli, resulting from dominance or from submission

if subordinate male begins male to male counters against the dominant male, the result would be

An increase in the activity of the GNRF GENE and increase in the number of GNRF receptors in the pituitary. The releasing factor would also caused a change in pigmentation, resulting in a brighter, more colorful fish, asserting its dominance.

Another factor playing a role in dominant aside from GNRF is

Body size, larger bodies are more dominant

When a male has achieved dominance, the gene controlling the release of_is turned on

Somatostatin

Somatostatin

Inhibitor release of growth hormone, decreasing the growth rate and dominant males. If the Dominant male begins to lose Dominant display, Thisproduction decreases and GH increases allow for increased growth again.

Wendy BURTONI is killed off by a predator, a subordinate male has a quick opportunity to rise in the social structure. What is the genes that the subordinate male is stimulated to increase?

early GENE one/ERG – 1

ERG – one

Will cause a quick change to the dominant toleration and increase in dominant behavior. If the dominant male wins more often, then he loses, GNRF and somatostatin productive, increase, making him a truly dominant male.

What role does a Zenk gene play in song learning in songbirds?

Increases mRNA levels in the four brain when a bird hears unfamiliar songs, Aid short-term memory and learning, activity Decline once the song is recognized

How to Hormones influence complex Behavior

from internal or external sources, Can alter gene expression and affect behavior – for one example, do changes the steroid levels or exposure to hormones from an individual that belongs to the same species as the other individual

How did Jean expression pattern differ between sneaker And Migrating male Atlantic salmon

Male sneakers showed increased expression of reproductive related genes while immature, migrating males show activity in growth related affecting their Behavior and physical development

Gene activity can also be influenced by (Environmental)

Population density, food, available availability, lighting, temperature.

Epigenetics

The study of heritable changes in gene expression caused by mechanisms other than changing a nuclear type of the DNA molecule

DNA Methylation

Turns off a gene. It does this by adding a metal group to the siding basis in the DNA strand. This causes the history of proteins to be brought into the sequence area of the strand, and cost a tightening of the strand.

Histone acetylation

Turn the Gene on. And acetyl group from acetyl coenzyme A is transferred to the lysine amino acid in a histone protein. This causes the stones to wrap the DNA strand, less tightly, making it easier for transcriptional access.

How does maternal care affects stress levels in Rat offsprings?

Offspring of nurturing mothers have lower stress levels due to increase glucocorticoid receptor expression which helps regulate stress hormones

what behaviors defined a nurturing Rat mother

Licking grooming and nursing they often frequently

What is the role of glucose receptors in the brain of rat offspring?

They help regulate stress by forming a feedback loop with Glucocorticoids, which are stretch reducing hormones

How is the glucocorticoid receptor gene activated and nurture Rat offspring?

Maternal care increases serotonin, which triggers his acetylation, unwrapping, DNA and making the receptor gene easier to transcribe

What happens to the glucocorticoid, receptor, gene and offspring of non-nurturing mothers?

The genius methylated, resulting in Poor receptors and poor stress regulation

What is the epigenetic effect of maternal care and future mothering behavior and rats?

It alters the expression of a gene for estrogen, receptor hypothalamus affecting oxytocin receptor regulation

Why is the estrogen receptor important in maternal behavior?

Regulates oxytocin Receptor, which is necessary for maternal care behaviors

How does poor maternal care impact future generations of rats

It causes methylation of glucocorticoid and estrogen, receptor, genes, reducing oxytocin, signaling and leading to inherited poor maternal care

Which hormone is necessary from maternal care

Oxytocin

In what other ways may epigenetic changes can unfold

Influencing evolution and play a role in learning

How many epigenetic changes play role in learning?

Memory formation seems to require methylation in the regions of the hippocampus

gene involved in fruit fly courtship

FRU