Genetics, Behavior, Selection, Pheromones, and Hormones

What is human DNA like?

Human DNA is like a sentence with 23 lines, 20,000 words, and 3 billion letters. Each word is written twice—once by the father and once by the mother.

What are alleles?

Alleles are different versions of a gene. They can be dominant or recessive and determine traits.

What is genotype?

Genotype is the set of traits coded in a person's DNA. It's like the genetic blueprint.

What is phenotype?

Phenotype is the set of traits that actually show up in a person's body, appearance, or behavior.

Why are monozygotic twins useful for studying genes and behavior?

Monozygotic twins have the same DNA, so they help scientists study how genes affect behavior.

How do dizygotic twins differ from monozygotic twins?

Dizygotic twins have different DNA, while monozygotic twins share the same DNA.

What's a challenge in twin studies?

Twin studies can't remove environmental factors because twins often share similar experiences.

What's a problem with research on separated monozygotic twins?

Monozygotic twins are rarely separated at birth, so studies on separated twins may not represent the general population.

What does a concordance rate below 100% in twin studies mean?

It means that genes don't fully determine behavior because environmental factors also play a role.

Why are twin studies considered indirect measures of genetic inheritance?

Twin studies don't directly show how genes affect behavior, because environmental factors also influence the outcome.

What is epigenetics?

Epigenetics is the study of how environmental factors can change the way genes are expressed, without changing the DNA itself.

What is genetic mapping?

Genetic mapping looks at which gene is involved in a behavior and where it is located on the chromosome.

How do researchers study genetic mapping?

Researchers collect blood samples from family members where a behavior is common and check the DNA for genetic variations.

What are genetic markers?

Genetic markers are specific genetic variations (polymorphisms) that help identify the location of genes linked to certain behaviors.

What is linkage analysis?

Linkage analysis is a technique used to find out which genes are linked to certain behaviors by studying the inheritance patterns of genetic markers in families.

What is GWAS (Genome

Wide Association Study)? - GWAS is a research method used to find out if specific genes are linked to certain traits or diseases by studying the entire genome.

How does GWAS work?

In GWAS, researchers compare the DNA of people with a particular trait or disease to the DNA of people without it to find genetic differences.

What do researchers look for in a GWAS?

Researchers look for patterns or specific genetic variations (called SNPs) that are more common in people with a trait or disease.

What is a SNP (Single Nucleotide Polymorphism)?

A SNP is a tiny change in a single letter of the DNA sequence. It can be a key part of GWAS, helping identify genetic differences linked to traits.

What is the goal of GWAS?

The goal of GWAS is to find genetic markers that can help predict or understand diseases and traits, which could lead to better treatments or prevention strategies.

What is intrasexual selection?

Intrasexual selection is competition between one sex (usually males) for access to mates. The "strongest" usually gets to pass on their genes.

What is intersexual selection?

Intersexual selection is when members of one sex (usually females) choose mates from the other sex based on specific traits like dance, feathers, jawline, or muscle.

What is a pheromone?

A pheromone is a chemical released by an animal into the environment, which affects the behavior or physiology of other animals of the same species.

What are primer pheromones?

Primer pheromones cause slow, long-term changes in the body, like hormonal effects.

What are signaling pheromones?

Signaling pheromones cause quick changes in behavior, such as triggering mating.

What is a hormone?

A hormone is a chemical secreted by glands in the endocrine system that helps regulate various processes in the body.

How are hormones different from neurotransmitters?

Hormones are released into the bloodstream, while neurotransmitters are released from neurons to send signals between them.

Can hormones act as neurotransmitters?

Yes, some hormones can act like neurotransmitters and attach to receptor sites on postsynaptic neurons.

Where do most hormones travel in the body?

Most hormones travel through the bloodstream and attach to receptors in different parts of the body to produce effects.